## Preamble

This document is intended to be a reference manual for Apache Axis2/C. This manual details how Axis2/C can be used to provide and consume Web services.

Please send your feedback to the Apache Axis2/C developer mailing list (axis-c-dev@apache.org). Subscription details are available on the Apache Axis2/C website.

This document uses the following conventions:

- The directory each package is installed in is given with an "_INSTALL_DIR" suffix to the package name. For example, the path in which Libxml2 is installed is referred to as LIBXML2_INSTALL_DIR

## Axis2/C Manual - Contents

1. Quick Start Guide
2. Repository Folder
3. Service API
4. Client API
5. REST
6. MTOM
7. Engaging a Module
8. WS-Addressing
9. Writing a Module
10. Simple Axis Server
11. Deploying with Apache2 HTTP Web Server
12. Deploying with Microsoft IIS Server
13. Using SSL Client
14. Using Proxy Support
15. Using Proxy Authentication Support
16. Using HTTP Authentication Support
17. WSDL2C Tool
18. TCP Transport
19. AMQP Transport
20. Archive Based Deployment
21. TCPMon Tool
22. Appendix A - axis2.xml
23. Appendix B - services.xml
24. Appendix C - module.xml
25. Appendix D - service client options

## 1. Quick Start Guide

This section is aimed to help you get a Web service running in a short time using Axis2/C, and consume that service using an Axis2/C client.

First, download the latest binary release from Apache Axis2/C. Once you download the correct binary that suits your platform, all that you require to get it running is to extract the package to a folder of your choice, and set the WSFCPP_HOME environment variable to point to this extracted folder. For Linux, you may have to set the LD_LIBRARY_PATH environment variable to include the lib folder (e.g. add $WSFCPP_HOME/lib). For MS Windows, you will have to add the lib folder to your PATH variable to include the Axis2/C DLLs to your path.

Now you should be able to change the directory to the bin folder of the extracted folder, and run the simple axis server in one command shell. Then change the directory to samples/bin in another command shell and run any of the samples there (you may have to set the environment variables in this new shell as well). Please see the installation guide for more details.

Once you have Axis2/C up and running successfully, you can start writing your own services and clients. The following sections explain how to write your first service and client with Axis2/C.

### 1.1 Hello Service

Let's see how you can write your first Web service with Axis2/C and how to deploy it.

The first service that we are going to write is named "hello" with a single operation named "greet" in the service. This "greet" operation, when invoked by the client, will expect the client to send a greeting in the request, and in turn send a greeting in the response. Following are examples of XML payloads exchanged between the client and the service:

Request:

     <greet>
     Hello Service!
     <greet>

Response:

     <greetResponse>
     Hello Client!
     <greetResponse>

The steps to be followed when implementing a service with Axis2/C include:

1. Implement the functions corresponding to the operations of the service.
   In our sample, we will have one function that implements the "greet" operation.
   We will name that function `axis2_hello_greet`.
2. Implement the functions defined by the `axis2_svc_skeleton` interface
   `axis2_svc_skeleton` interface expects the functions `init`, `invoke`, `on_fault` and `free` to be implemented by our service.
   In our sample, we would implement those and name them as `hello_init`, `hello_invoke`, `hello_on_fault` and `hello_free` respectively.
3. Implement the create function, that would create an instance of the service skeleton
   The create function would create an axis2_svc_skeleton and assign the respective function pointers to map the axis2_svc_skeleton interface to our interface implementation methods explained in the above step.
4. Implement axis2_get_instance and axis2_remove_instance functions
   These functions are used to create and destroy service instances by the engine, and each service must define these functions.
5. Write the services.xml file for the service
   The services.xml file acts as the deployment descriptor file for the service. As the bare minimum, we need to configure the service name, operations, and the shared library file name containing the service implementation in this file.
   As previously decided, we will name the service "hello", the operation "greet" and the shared library libhello.so on Linux and hello.dll on MS Windows.

### 1.1.1 Operation Implementation

Look for the `axis2_hello_greet` function in the hello_svc.c source file.

This function implements the business logic for the greet operation. We will be calling this function from our implementation of the invoke function. Basically, this function receives the request payload as an `axiom_node`, process it to understand the request logic, and prepares the response as an `axiom_node` and returns that.

### 1.1.2 Skeleton Create Method

Look for the `axis2_hello_create` function in the hello_svc.c source file.

The create function creates and returns a new `axis2_svc_skeleton` instance. The most important aspect to note about this function is the function pointer assignments. They are used to map the interface operations to the corresponding functions of the implementation. This is done by assigning the ops member of the service skeleton to the address of the ops struct variable.

### 1.1.3 Invoking Operation Implementation

The invoke method of the service skeleton is the point of entry for invoking the operations. Hence in our implementation of the invoke function, we have to define how the operations are to be called.

Look for the `hello_invoke` function in the hello_svc.c source file.

In our implementation of the `hello_invoke`, we call the function implementing the greet operation. As we have only one operation, the task is simple here. If we had multiple operations, we will have to look into the information in the message context to map it to the exact operation.
The Axis2/C engine will call the invoke method with an `axiom_node`, containing the request payload, and `axis2_msg_ctx` instance, containing the message context information, in addition to the service skeleton and the environment pointers. We can use the message context to extract whatever information we deem necessary that is related to the incoming message. The Axis2/C engine expects the invoke method to return a pointer to an `axiom_node`, representing the response payload.

### 1.1.4 Full Source

Here is the complete source code for the service : hello_svc.c

### 1.1.5 Service Descriptor

The services.xml file contains details on the service that would be read by the Axis2/C deployment engine during server start up time. The following shows the contents for the services.xml file for the hello service.

    <service name="hello">
     <parameter name="ServiceClass" locked="xsd:false">hello</parameter>
     <description>
     Quick start guide hello service sample.
     </description>
     <operation name="greet"/>
    </service>

The service configuration shown above specifies that the name of the service is hello.
The value of the "ServiceClass", "hello" in this case, will be mapped to the service implementation by the deployment engine as libhello.so on Linux or hello.dll on MS Windows. The description element contains a brief description of the service.
There can be one or more operation elements. For this sample, we only have one operation, with the name "greet".

### 1.1.6 Compiling the Service

You can compile the service sample as shown below.

On Linux:

    gcc -shared -olibhello.so -I$WSFCPP_HOME/include/axis2-1.6.0/ -L$WSFCPP_HOME/lib -laxutil -laxis2_axiom -laxis2_parser -laxis2_engine -lpthread -laxis2_http_sender -laxis2_http_receiver hello_svc.c

On MS Windows:

to compile,

    cl.exe /D "WIN32" /D "_WINDOWS" /D "_MBCS" /D "AXIS2_DECLARE_EXPORT" /D "AXIS2_SVR_MULTI_THREADED" /w /nologo /I %WSFCPP_HOME%\include /c hello_svc.c

to link,

    link.exe /nologo /LIBPATH:%WSFCPP_HOME%\lib axutil.lib axiom.lib axis2_parser.lib axis2_engine.lib /DLL /OUT:hello.dll *.obj

### 1.1.7 Deploying the Service

To make the service available to be consumed by the clients, we have to deploy the service. To deploy the service, you have to create a folder named 'hello' in the WSFCPP_HOME/services folder, and copy the services.xml file and the shared library file (libhello.so on Linux or hello.dll on MS Windows) into that folder.

To verify that your service has been correctly deployed, you can start the simple axis server and then browse the list of deployed services using a Web browser. To start the simple axis server, you can go to the WSFCPP_HOME/bin folder and run the executable axis2_http_server. The default URL that you can test the service list with is http://localhost:9090/axis2/services. You should get an entry for the hello service on the page that is displayed.

### 1.1.8 Providing a WSDL for the Service

Axis2/C does not support dynamic WSDL generation. However, it is possible to attach the contract you used to generate the service skeleton, to the respective service. This can be done in two ways.

1. Adding the WSDL file to the folder in which the service DLL is found.
2. Providing the path of the WSDL file in the services.xml.

If you choose the first option, you will have to copy the WSDL file to the folder in which the service DLL is found. The name of the WSDL file should be the name of the service. And, if you choose the second option, you will have to make use of the `wsdl_path` parameter in the services.xml file. More info on how this can be done is found under the services.xml section.

An example of the second option can be found the services.xml of the echo sample service, which is commented. An example of the first option in use is seen in the Calculator sample service.

The static WSDL file can be accessed by appending `?wsdl` to the service end-point. You can view the WSDL provided for the Calculator sample, by pointing to http://localhost:9090/axis2/services/Calculator?wsdl.

### 1.2 Hello Client

Now that you know how to write a service with Axis2/C, let's see how to write a client to consume that service. The request payload that the client will be sending to the service was described in the previous section. The client has to prepare the payload, send it to the service, and then receive and process the response.

The steps to be followed when implementing a client with Axis2/C:

1. Create the environment to be used by the client.
   Each function in Axis2/C takes a pointer to the environment instance that encapsulates the memory allocator, error handler, and logging and threading mechanisms. The `axutil_env_create_all` method can be used to create a default, ready to use environment instance.
2. Create an options instance, and set options.
   The`axis2_options` struct can be used to set the client side options. For example, we can use options to set the endpoint address of the service to be consumed by the client.
3. Create a service client instance, giving the client repository folder as a parameter.
   The`axis2_svc_client` struct is meant to be used by the users to consume Web services. It provides an easy to use API. Service client create method takes the location of the repository as a parameter. For the purpose of our sample, you can use the WSFCPP_HOME as the repository. The concept of repository is explained in detail in a later section.
4. Set options to service client instance
   The options created in an earlier step have to be set on the service client, indicating the options that are meant to be used by the service client.
5. Send the request and receive the response
   The service client's `axis2_svc_client_send_receive` method can be used to invoke the send receive operation on the service client instance.
   The send receive operation takes the request payload as an `axiom_node` and returns the response payload as an `axiom_node`.
6. Process the response
   Process the response in line with the client business logic.

### 1.2.1 Creating and Setting Options

     options = axis2_options_create(env);
     address = "http://localhost:9090/axis2/services/hello";
     endpoint_ref = axis2_endpoint_ref_create(env, address);
     axis2_options_set_to(options, env, endpoint_ref);

In the above section of code, an `axis2_options` instance is created first. Then an endpoint reference instance is created with the address of the location of the service. Finally, the created endpoint is set as the "to" address of the options. The "to" address indicates where the request should be sent to.

### 1.2.2 Using Service Client

     svc_client = axis2_svc_client_create(env, client_home);
     axis2_svc_client_set_options(svc_client, env, options);
     payload = build_om_request(env);
     ret_node = axis2_svc_client_send_receive(svc_client, env, payload);

After creating and preparing the options, the next step is to create a service client instance and use it to send the request and receive the response. The code fragment given above shows how options can be set on top of the service client and how to invoke the send receive operation with a request payload. Once the response is received, the response payload will be stored in the `ret_node`, which is a pointer to an `axiom_node` that can be used to process the response further.

### 1.2.3 Full Source

Here is the complete source code for the client : hello.c

### 1.2.4 Compiling the Client

You can compile the client sample as shown below.

On Linux:

    gcc -o hello -I$WSFCPP_HOME/include/axis2-1.6.0/ -L$WSFCPP_HOME/lib -laxutil -laxis2_axiom -laxis2_parser -laxis2_engine -lpthread -laxis2_http_sender -laxis2_http_receiver hello.c -ldl -Wl,--rpath -Wl,$WSFCPP_HOME/lib

On MS Windows:

to compile,

    cl.exe /nologo /D "WIN32" /D "_WINDOWS" /D "_MBCS" /I %WSFCPP_HOME%\include /c hello.c

to link,

    link.exe /LIBPATH:%WSFCPP_HOME%\lib axutil.lib axiom.lib axis2_parser.lib axis2_engine.lib /OUT:hello.exe *.obj

### 1.2.5 Running the Client

To run the client, make sure you start the simple axis server and then run the hello executable.

## 2. Repository Folder

Repository is a folder where all Axis2/C related configurations as well as services and modules are located. The following shows the folder structure of the repository:

Here the name of the repository folder is axis2c_repo. In your system, you can specify any folder name of your choice. There are three sub folders available in the repository. In addition to that, the axis2.xml configuration file is also located in the repository. The following table describes the purpose of the repository contents.

Axis2/C Repository Contents
Folder/File Name | Description
--- | ---
lib | The lib folder contains the libraries required to run the Axis2/C engine. While you can afford to have the shared libs of Axis2/C in a location of your choice, the dynamically loaded shared libs, parser, transport receiver and transport sender has to be in the repository lib folder. It is mandatory that the lib folder is there in the repository.
modules [optional] | The modules folder contains the modules deployed with Axis2/C. Each module deployed will have its own sub folder inside the modules folder. For example, if the addressing module is deployed, then there will be a sub folder named addressing inside the modules folder of the repository. At deployment, the Axis2/C deployment engine would traverse the modules folders to find out what modules are available. The modules folder is optional. If it is empty or non-existent, that means that there are no deployed modules.
services [optional] | The services folder contains the services deployed with Axis2/C. Each service deployed will have its own sub folder inside the services folder, or live inside one of the sub folders. At deployment, the Axis2/C deployment engine will traverse the services folders to find out what services are available. The services folder is optional. If it is empty or non-existent, that means that there are no deployed services.
axis2.xml | The axis2.xml file is the configuration file of Axis2/C. The configuration file is mandatory and must have the name axis2.xml. It is safe to consider your Axis2/C repository to be the folder in which you have the axis2.xml file.

Both clients as well as the services written using Axis2/C can use the same repository. However you can use one repository for the server side and another one for the client side. The services folder is used only when the repository is used by the server side. When the repository is used by the client, the services folder, if present, will not be used.

The Axis2/C binary distribution, when extracted, can be considered as ready for use as your repository folder. If you are building Axis2/C from the source distribution, when you build the source, including the samples, the installation destination will be ready for use as your repository folder.

The simple axis server (that is axis2_http_server binary), the client samples, and the HTTPD module (Axis2 Apache2 module) require the repository folder to be specified in order to run correctly.

### 2.1 Module Folders

As described earlier, all the modules are placed inside the modules folder of the repository, and each module will have its own sub folder within the modules folder.
The folder in which a module is placed must have the same name as the module name. For example, the addressing module will be placed in a sub folder named addressing.

Inside the folder corresponding to a module, the shared library implementing the module and the module configuration file, module.xml, is placed. It is a must that these two files are present inside each folder representing a module. The module.xml file will be processed by the deployment engine to find out module specific information such as the module name, set of handlers, the flows into which those handlers are to be added, etc.

### 2.2 Service Folders

All the services are placed inside the services folder of the repository, and each service will be in one of the sub folders within the services folder. Axis2/C has a concept called service groups, where there can be one or more services inside a service group. A single stand alone service is assigned a service group with the same name as that of the service by the Axis2/C engine for the purpose of easy handling. Therefore the sub folders in the services folder correspond to the service groups.

A service, if deployed as a stand alone service, will reside inside a folder with the same name as that of the service. For example, the echo service will be placed in a sub folder named echo. The shared library implementing the service and the service configuration file, the services.xml, will be placed inside the folder corresponding to a service. Given the fact that the engine treats the folders to represent service groups and not a single service, the configuration file is called services.xml. However, you can always place a single service inside a single folder, which is the most common use case.

Each sub folder within the services folder should have at least one shared lib implementing a service and a services.xml file. If it is a real service group, there will be multiple shared libs, yet there is only one services.xml file configuring all those services. The services.xml file is processed by the deployment engine to find out the service group and the service specific information such as the service group name, service name, the set of operations for each service, etc.

## 3. Service API

We have already seen how to write a service in the Quick Start Guide section of this manual. This section covers the service API of Axis2/C in more detail.

`axis2_svc_skeleton` is an interface. Axis2/C does not provide any concrete implementation of this interface. It is the responsibility of the service implementer to implement this interface. To implement the interface, you should implement the functions adhering to the function pointer signatures of the members of the `axis2_svc_skeleton_ops` struct. Then, a create function should be written to create an `axis2_svc_skeleton` instance, and assign the implementing functions to the members of the ops member of service skeleton.

The following table details the signatures of the function pointer members of the `axis2_svc_skeleton` struct implemented by a service.

Function Signature | Description
--- | ---
    int (AXIS2_CALL *
     init)(axis2_svc_skeleton_t *svc_skeleton,
     const axutil_env_t *env);
| Initializes the service skeleton object instance. The Axis2/C engine initializes a service skeleton instance once per deployed service, during the first request made to the service.
    axiom_node_t *(AXIS2_CALL*
     invoke )( axis2_svc_skeleton_t *svc_skeli,
     const axutil_env_t *env,
     axiom_node_t *node,
     axis2_msg_ctx_t *msg_ctx);
| Invokes the service implementation. You have to implement the logic to call the correct functions in this method based on the name of the operation being invoked.
    axiom_node_t *(AXIS2_CALL*
     on_fault)(
     axis2_svc_skeleton_t *svc_skeli,
     const axutil_env_t *env,
     axiom_node_t *node);
| This method is called by the engine if a fault is detected.
    axis2_status_t (AXIS2_CALL *
     free )( axis2_svc_skeleton_t *svc_skeli,
     const axutil_env_t *env);
| Frees the service implementation instance.

There are two more methods that a service should implement. Once a service is deployed, the message receiver of the Axis2/C engine has to create a service instance at run time for the purpose of invoking it. For this, it looks for a method named `axis2_create_instance` and calls it on the service shared library. The engine also looks for a function named `axis2_remove_instance` in the shared library for clean up purposes.

Function Signature | Description
--- | ---
    AXIS2_EXPORT int
    axis2_get_instance(
     axis2_svc_skeleton_t ** inst,
     const axutil_env_t * env);
| Creates an instance of the service. You have to implement the logic of creating the service object, allocating memory etc. in this method.
    AXIS2_EXPORT int
    axis2_remove_instance(
     axis2_svc_skeleton_t * inst,
     const axutil_env_t * env);
| Removes the instance of the service. Do any cleaning-up and deallocations here.

Note that service object instantiation happens once per service. When the first request is received by the service, a service skeleton instance is created and initialized. The same object instance will be re-used by the subsequent requests.

You can find an example on how to implement the service skeleton interface in the hello_svc.c source file, which is the example used in the Quick Start Guide. More advanced samples can be found in the samples folder of the Axis2/C distribution.

## 4. Client API

The primary client API to be used with Axis2/C is `axis2_svc_client`, the service client API. This is meant to be an easy to use API for consuming services. If you want to do more complex tasks, such as invoking a client inside a module, or wrap the client API with another interface, you may need to use `axis2_op_client`, the operation client API. For most of the use cases, the service client API is sufficient.

The behavior of the service client can be fine tuned with the options passed to the service client. You can set the options by creating an `axis2_options` instance. The bare minimum that you need to set is the endpoint URI to which the request is to be sent. An example of this was given in the Quick Start Guide section.

The service client interface serves as the primary client interface for consuming services. You can set the options to be used by the service client and then invoke an operation on a given service. There are several ways of invoking a service operation. The method of invoking an operation depends on 3 things. They are,

1. The Message Exchange Pattern (MEP)
2. Synchronous/Asynchronous behavior (Blocking/Non-Blocking)
3. Two-way or one-way transport

Many service operation invocation scenarios can be obtained by combining the above three factors. The service client interface provides the necessary API calls to achieve this.

Deciding the Message Exchange Pattern (MEP)

There are 2 message exchange patterns.

1. Out-Only
2. Out-In

In the Out-Only MEP, the client doesn't expect a reply from the server. The service client provides two methods of using the Out-Only MEP.

Function Signature | Description
--- | ---
    AXIS2_EXTERN void AXIS2_CALL
     axis2_svc_client_fire_and_forget(
     axis2_svc_client_t * svc_client,
     const axutil_env_t * env,
     const axiom_node_t * payload);
| Sends a message and forgets about it. This method is used to interact with a service operation whose MEP is In-Only. There is no way of getting an error from the service using this method. However, you may still get client-side errors, such as host unknown.
    AXIS2_EXTERN axis2_status_t AXIS2_CALL
     axis2_svc_client_send_robust(
     axis2_svc_client_t * svc_client,
     const axutil_env_t * env,
     const axiom_node_t * payload);
| This method too is used to interact with a service operation whose MEP is In-Only. However, unlike `axis2_svc_client_fire_and_forget`, this function reports an error back to the caller if a fault triggers on the server side. When using Out-In MEP, the client expects a reply from the server. `axis2_svc_client_send_receive` and `axis2_svc_client_send_receive_non_blocking`functions support this MEP
     AXIS2_EXTERN axiom_node_t *AXIS2_CALL
     axis2_svc_client_send_receive(
     axis2_svc_client_t * svc_client,
     const axutil_env_t * env,
     const axiom_node_t * payload);
| This method is used to interact with a service operation whose MEP is In-Out. It sends an XML request and receives an XML response. Returns a pointer to the AXIOM node representing the XML response. This method blocks the client until the response arrives.
    AXIS2_EXTERN void AXIS2_CALL
     axis2_svc_client_send_receive_non_blocking(
     axis2_svc_client_t * svc_client,
     const axutil_env_t * env,
     const axiom_node_t * payload,
     axis2_callback_t * callback);
| This method too, is used to interact with a service operation whose MEP is In-Out. It sends an XML request and receives an XML response, but the client does not block for the response. In this method, the client does not block for the response, but instead it expects the user to set a call back to capture the response.

Please have a look at the `axis2_svc_client.h` header file for more information on the above mentioned functions, as well as their synonyms that accept an operation's qualified name.

### 4.1 Synchronous vs. Asynchronous Behavior (Blocking/Non-Blocking)

This will determine whether the client would block for the response (synchronous) or return immediately expecting the response to be handled by a callback (asynchronous, in other words non-blocking) in an Out-In MEP scenario.
`axis2_svc_client_send_receive` operates in synchronous mode, whereas `axis2_svc_client_send_receive_non_blocking` operates in asynchronous mode.

### 4.2 Two-Way or One-Way Transport

If the transport is two-way, then only one channel is used, which means the request is sent and the response is received on the same channel. If the transport is one-way, then the request is sent on one channel and the response is received on a separate channel.
If we want to use a separate channel for the response, a separate listener has to be started to receive the response, This can be done by setting the separate listener option to True using the `axis2_options_set_use_separate_listener` function above the options.

Please have a look at the `echo_blocking_dual` sample to see how to set the separate channel option.

Please see Appendix D for further details on setting options.

## 5. REST

Axis2/C comes with plain old XML (POX) like REST support. A given service can be exposed both as a SOAP service as well as a REST service. By default, your service will support SOAP as well as REST, however, your service operations will only be available for SOAP. In order to enable REST for your operations you need to add one or more parameters under your operation, in the services.xml. If you want to consume Web services using REST style calls, you can use the HTTP POST method, the HTTP GET method, the HTTP HEAD method, the HTTP PUT method or the HTTP DELETE method.

### 5.1 REST on Client Side

The following example code fragment shows how to set up a client enabling a REST style invocation.

    axis2_options_set_enable_rest(options, env, AXIS2_TRUE);

You can use the same code that you use with a SOAP call, and do REST style invocation by just enabling REST using the option setting shown above.

The default HTTP method used with REST is HTTP POST. If you need to change it to the HTTP GET method, the following needs to be done.

    axis2_options_set_http_method(options, env, AXIS2_HTTP_GET);

Similarly you can use AXIX2_HTTP_HEAD to change it to the HTTP HEAD method, or AXIX2_HTTP_PUT to change it to the HTTP PUT method, or AXIX2_HTTP_DELETE to change it to the HTTP DELETE method.

Please have a look at the `echo_rest` sample for a complete source code on how to use REST.

### 5.2 REST on Server Side

You basically need to add the REST Location, and the REST Method parameters to the services.xml to enable REST in a service operation. The REST location is the template that needs to be matched to find your operation, and the REST Method is the HTTP Method associated with the service. Note that the REST Method is optional for each operation. If no REST Method is specified, POST, will be assumed. Optionally you may specify the default REST Method for all operations at the service level. Then, if you haven't specified a REST Method for your operation, the default REST Method specified will be assumed instead of POST. Please have a look at the `echo` sample service for a complete source code on how to set up REST. Shown below is an example, on how to configure the `locate` operation to work with HTTP GET on REST.

    <operation name="locate">
     <parameter name="RESTMethod">GET</parameter>
     <parameter name="RESTLocation">location/{lat}/{long}</parameter>
    </operation>

The corresponding request would look like, `http://www.sample.org/service/location/34N/118W`, which would return Los Angeles, California. In here, the portion `location` is fixed and `lat` and `long` are optional parameters which will be captured to the payload.

### 5.3 REST and SOAP for Same Operation

It is also possible to enable a single service operation for SOAP as well as REST. This can be done by specifying a REST Location that does not contain the operation name. The `locate` operation is an example to such a case. Thus, for a SOAP invocation, you need to use `http://www.sample.org/service/locate`, as the end point or WS-Addressing Action.

## 6. MTOM

Axis2/C allows you to send and receive binary data with SOAP messages using MTOM/XOP conventions. When sending and receiving attachments, you have to use the service client (`axis2_svc_client`) API to perform the send and receive operations, and provide or consume binary data in relation to the AXIOM payloads.

In order to send a binary attachment, you need to build the AXIOM payload and attach the data handler with binary content to the payload.

    <soapenv:Body>
     <ns1:mtomSample xmlns:ns1="http://ws.apache.org/axis2/c/samples/mtom">
     <ns1:fileName>test.jpg</ns1:fileName>
     <ns1:image>
     <xop:Include xmlns:xop="http://www.w3.org/2004/08/xop/include"
     href="cid:1.f399248e-8b39-1db1-3124-0015c53de2e5@apache.org"></xop:Include>
     </ns1:image>
     </ns1:mtomSample>
    </soapenv:Body>

In the above sample payload shown, we place our image file as text within an image element

    image_om_ele = axiom_element_create(env, mtom_om_node, "image", ns1, &image_om_node);
    data_handler = axiom_data_handler_create(env, image_name, "image/jpeg");
    data_text = axiom_text_create_with_data_handler(env, image_om_node, data_handler, &data_om_node);

When sending attachments, you can configure the client either to send the attachment in the optimized format or non-optimized format.

To do this, set the option `axis2_options_set_enable_mtom(options, env, AXIS2_TRUE);`or the setting `<enableMtom>true</enableMtom>` in axis2.xml

If enableMTOM is set to True, the attachment is sent as it is, out of the SOAP body, using MIME headers. Also the payload will have an XOP:Include element, referring to the MIME part that contains the binary attachment. Sending the attachment as it is, in pure binary format, is called binary optimized format. In the case of binary non-optimized format, where enableMTOM is False, the attachment content is sent in the payload itself, as a base64 encoded string.

### 6.1 Using MTOM Callbacks

Axis2/C Can send and receive very large attachments with a very low memory foot print. User can specify callbacks to load attachments before sending and store attachments while recieving.

#### 6.1.1 Sender side Callback

The attachment can be loaded from any data source. User need to implement the callback using axiom_mtom_sending_callback.h. A sample Callback can be found here. Following is what need to be done with data_handler in the case of a callback.
data_handler = axiom_data_handler_create(env, NULL, content-type);
axiom_data_handler_set_data_handler_type(data_handler, env, AXIOM_DATA_HANDLER_TYPE_CALLBACK);
axiom_data_handler_set_user_param(data_handler, env, (void *)user_param);

user_param is of any type which the user should know how to handle from the callback. The path to the implemented callback should be specified in the axis2.xml as follows.

<parameter name="MTOMSendingCallback" locked="false">/path/to/the/attachment_sending_callback</parameter>

#### 6.1.2 Receiver side callback

For large attachments users can specify them to be cached either to a file or to a any storage. In order to enable caching user should set either "attachmentDir" or "MTOMCachingCallback" parameters in the axis2.xml. If both are set the callback will be used. If nothing is set attachment will reside in memory.

Following is an example of specifying the attachmentDir.

<parameter name="attachmentDIR" locked="false">/path/to/the/dir/</parameter>

So the attachments will be saved in the specified directory using the attachment content id as the file name.

In the callback case the callback should be implemented using axiom_mtom_caching_callback.h. The following paramter will enbale the caching callback.

<parameter name="MTOMCachingCallback" locked="false">/path/to/the/attachment_caching_callback</parameter>

A sample callback implementation can be found here.

Axis2/C allows to set the caching threshold. The default is 1MB. For example to cache attachments which are greater than 10MB in size user need to add the following directive in axis2.xml.

<parameter name="MTOMBufferSize" locked="false">10</parameter>

This will give the control to the users to use the availbale memory even with larger attachments.

When the attachment is cached the ultimate receiver can always identify it by calling ,

if (axiom_data_handler_get_cached(data_handler, env))
{
/* logic for attachment handling */
}

The logic on how to handle the attachment will depend on the mechanism which is used to cached the attachment.

Please have a look at the MTOM related samples in the Axis2/C samples directory.

## 7. Engaging a Module

A module is a set of handlers that helps to extend the message processing behavior of the Axis2/C engine. Modules have the concepts of being Available and Engaged associated with them. Available means modules are deployed in the system but not activated. They will be activated only after being engaged. Every module comes with its own module.xml file . This module.xml file specifies the module specific handlers and the phases into which the handlers are to be placed in the handler chain. Some of the module specific handlers may be put into system predefined phases. In that case, the module.xml file should specify where to put the handlers relative to the others in that phase. Sometimes a module may define its own phase. In that case, some of the module specific handlers may be put into that phase. The handlers added to the system predefined phases (global handlers) are invoked for every message that comes to or goes out from the system. The handlers in the module specific phase are invoked only for the messages invoking the operations that engage that module. Engaging a module means correctly adding the handlers of a particular module to one or more phases. Once the module is engaged, the handlers and the operations defined in the module are added to the entity that engaged them.

Before engaging a module, the following steps have to be followed.

1. Write the module.xml file
2. Package the module libraries and the module.xml into a folder which has the same name as the module
3. Deploy the folder in AXIS2C_INSTALL_DIR/modules
4. Add the module specific phases in the axis2.xml file

The following is an example of engaging a sample module called the logging module with Axis2/C:

### 7.1 Writing the module.xml File

In the module.xml file, the handlers of the module and the phases to which they are to be added have to be specified. Below is the module.xml file of the sample logging module.

     <module name="logging" class="axis2_mod_log">
     <inflow>
     <handler name="LoggingInHandler" class="axis2_mod_log">
     <order phase="PreDispatch"/>
     </handler>
     </inflow>
     <outflow>
     <handler name="LoggingOutHandler" class="axis2_mod_log">
     <order phase="MessageOut"/>
     </handler>
     </outflow>
     <Outfaultflow>
     <handler name="LoggingOutHandler" class="axis2_mod_log">
     <order phase="MessageOut"/>
     </handler>
     </Outfaultflow>
     </module>

In the above shown module configuration file, the name of the module is logging. There are two handlers in this module, the LoggingInHandler and the LoggingOutHandler. The LoggingInHandler is placed into the PreDispatch phase of the in flow. The LoggingOutHandler is placed into the MessageOut phase of both the out flow and the fault out flow.

### 7.2 Packaging and Deploying the Module

The above module.xml file should be copied to a folder named "logging" (because the module name is "logging") inside the AXIS2C_INSTALL_DIR/modules folder. The module libraries containing the handler implementation should also be copied to the same folder. According to the module.xml file shown above, the name of the shared library file should be libaxis2_mod_log.so on Linux and axis2_mod_log.dll on MS Windows.

### 7.3 Adding Module Specific Phases to the axis2.xml File

Module specific phases have to be added after the system predefined phases. The following example shows where to add the module specific phases. Look for the `phaseOrder` elements in the axis2.xml file. Note the comment lines:

     <!-- User defined phases could be added here -->

You can add user defined phases after the above comment line into any of the flows. The `type` attribute of the `phaseOrder` element indicates the flow.

For the logging module example, user defined phases are not required. All the module specific handlers are added to system predefined phases as specified in the module.xml file.

### 7.4 Engaging a Module to a Services

The following is an example of engaging the logging module to the echo service. This can be done by simply adding `<module ref ="logging"/>` in the services.xml file of the echo service. This informs the Axis2/C engine that the module "logging" should be engaged for this service. The handlers inside the module will be executed in their respective phases as described by the module.xml.

     <service name="echo">
     <module ref ="logging"/>
     <parameter name="ServiceClass" locked="xsd:false">echo</parameter>
     <description>
     This is a testing service, to test if the system is working or not.
     </description>
     <operation name="echoString">
     <!--messageReceiver class="axis2_receivers" /-->
     <parameter name="wsamapping" >
     http://ws.apache.org/axis2/c/samples/echoString
     </parameter>
     </operation>
     </service>

One important thing to note here is that because the logging module's handlers are placed into the global phases, even though the logging module is engaged only to the echo service, the module will be engaged globally. This is a feature of the Axis2 architecture, not a bug. When invoked, the handlers in a module can check whether the module has been engaged to a particular service, and act accordingly.

### 7.4.1 Engaging a Module Globally

If we want to engage a module for every service deployed in the Axis2/C system, we can add the `<module ref ="logging"/>` entry in the axis2.xml file. This will inform the Axis2/C engine to invoke the handlers associated with the module for every message coming in or going out for all the services deployed.

### 7.5 Engaging a Module on the Client Side

On the client side, if `<module ref ="logging"/>` is added in the axis2.xml, the handlers specific to the logging module will be invoked for every request the client sends and every response the client receives. If only a particular client wants to engage the module, it can be done by engaging the module programmatically. This can be done by adding the following line in the client code after setting the options.

    axis2_svc_client_engage_module(svc_client, env, "module-name");

Remember to replace "module-name" with the name of the module you want to engage. For example to engage the logging module you can use:

    axis2_svc_client_engage_module(svc_client, env, "logging");

## 8. WS-Addressing

WS-Addressing provides mechanisms to address Web services and messages. With Axis2/C, you can use both WS-Addressing version 1.0 as well as the submission version.

WS-Addressing is implemented as a module in Axis2/C. Hence as explained in the previous section, the addressing module can be engaged both on the client side as well as on the server side.

The WS-Addressing module can be globally engaged by adding the `<module ref="addressing"/>` line to the axis2.xml file.

The WS-Addressing module can also be programmatically engaged using the following line of code with the service client API

    axis2_svc_client_engage_module(svc_client, env, AXIS2_MODULE_ADDRESSING);

WS-Addressing related options can be set using the `axis2_options` struct instance on the client side. If the addressing module is engaged, there are no options to be set on the server side. The server will employ WS-Addressing if the incoming requests have WS-Addressing headers.

There is a mandatory requirement for using WS-Addressing on the client side with Axis2/C. That is to set a WS-Addressing action that represents the operation to be invoked. Example:

    axis2_options_set_action(options,env,"http://ws.apache.org/axis2/c/samples/echoString")

In addition to the action, which is mandatory, there are other WS-Addressing related headers that can be sent in a message. Axis2/C supports to set those headers as options at the client level. The following functions are used to set them.

    axis2_options_set_reply_to(options, env, reply_to)

Sets the `wsa:ReplyTo` header. The ReplyTo header contains the endpoint to send reply messages. The ReplyTo header is required when the response comes in a separate channel (when using a dual channel).

    axis2_options_set_fault_to(options, env, fault_to)

Sets the `wsa:FaultTo` header. This contains the endpoint to direct fault messages.

    axis2_options_set_from(options, env, from)

Sometimes the receiving endpoint requires to know the original sender of the message. The `wsa:From` header is used in such cases. The above function sets the From header.

    axis2_options_set_relates_to(options, env, relates_to)

Sets the `wsa:RelatesTo` header. This header contains a unique ID which is the message ID of a previously exchanged message. It helps to identify a previous message that relates to the current message.

## 9. Writing a Module

A module is an extension point in the Axis2/C engine. Modules are primarily used to WS-* specifications. In other words, quality of service aspects such as security and reliable messaging can be implemented as modules and deployed with the Axis2/C engine.
A SOAP message can contain any number of header blocks. These header blocks provide various processing information. In Axis2/C, these various header blocks are processed by modules. Some times modules may add header blocks to a SOAP message.

Normally a module is a collection of handlers. So writing a module mainly consists of writing handlers. There are two interfaces that are important when writing a module. They are `axis2_module` and `axis2_handler`.``

Every module should have three basic functions that are defined as function pointer members of the `axis2_module_ops` struct. This struct is defined in the `axis2_module.h` header file.

Function Signature | Description
--- | ---
    axis2_status_t (AXIS2_CALL *
     init)(axis2_module_t *module, const
     axutil_env_t *env,
     axis2_conf_ctx_t *conf_ctx,
     axis2_module_desc_t *module_desc);
| This function takes care of the module initialization.
    axis2_status_t (AXIS2_CALL *
     shutdown)(axis2_module_t *module,
     const axutil_env_t *env );
| Shuts down and cleans up the module.
    axis2_status_t (AXIS2_CALL *
     fill_handler_create_func_map)(axis2_module_t *module,
     const axutil_env_t *env );
| This function fills the hash map of the handler create functions for the module.

The module developer has to implement functions with the above signatures and assign them to the members of an `axis2_module_ops` struct instance. Then that struct instance has to be assigned to the ops member of an `axis2_module` struct instance.

mod_log.c has the source for the logging module. Please have a look at the `axis2_mod_log_create` function in it to see how an `axis2_module` instance is allocated and how the ops are initialized.

The`axis2_mod_log_fill_handler_create_func_map` function adds the handler create functions to the module's hash map, which stores the handler create functions. In the mod_log.c example, the logging module adds two handlers. The in handler and the out handler that deals with logging along with the in-flow and out-flow respectively.

### 9.1 Writing Handlers

A handler is the smallest unit of execution in the Axis2/C engine's execution flow. The engine can have two flows, the in-flow and the out-flow. A flow is a collection of phases, and a phase in turn is a collection of handlers. A handler is invoked when the phase within which it lives is invoked. Axis2/C defines an interface called `axis2_handler`, which is to be implemented by all the handlers.

log_in_handler.c contains the source code of the in-handler of the logging module. Please have a look at the `axutil_log_in_handler_create` function to see how an `axis2_handler` instance is created and how the invoke function implementation, `axis2_log_in_handler_invoke` is assigned to the `axis2_handler` invoke function pointer. The invoke is called to do the actual work assigned to the handler. The phase that owns the handler is responsible for calling the invoke function of the handler.

log_out_handler.c contains the source code of the out handler of the logging module. The implementation is similar to the in handler, except that it is placed along the out-flow when deployed.

### 9.2 Writing the module.xml File

After writing the module, the module.xml file should be written. The module.xml file contains all the configuration details for a particular module. Please see the sample module.xml file for the logging module.

Please see the Engaging a Module section for more details on how to package and deploy the module.

## 10. Simple Axis2 HTTP Server

Simple Axis2 HTTP Server is the inbuilt HTTP server of Axis2/C.

### 10.1 Linux Based Systems

Synopsis :

     axis2_http_server [-p PORT] [-t TIMEOUT] [-r REPO_PATH] [-l LOG_LEVEL] [-f LOG_FILE] [-s LOG_FILE_SIZE]

You can use the following options with simple axis HTTP server.

     -p PORT port number to use, default port is 9090
     -r REPO_PATH repository path, default is ../
     -t TIMEOUT socket read timeout, default is 30 seconds
     -l LOG_LEVEL log level, available log levels:
     0 - critical 1 - errors 2 - warnings
     3 - information 4 - debug 5- user 6 - trace
     Default log level is 4(debug).
     -f LOG_FILE log file, default is $WSFCPP_HOME/logs/axis2.log
     or axis2.log in current folder if WSFCPP_HOME not set
     -s LOG_FILE_SIZE Maximum log file size in mega bytes, default maximum size is 1MB.
     -h display the help screen.

Example :

     axis2_http_server -l 3 -p 8080 -r $WSFCPP_HOME -f /dev/stderr

### 10.2 MS Windows Based Systems

Synopsis :

     axis2_http_server.exe [-p PORT] [-t TIMEOUT] [-r REPO_PATH] [-l LOG_LEVEL] [-f LOG_FILE] [-s LOG_FILE_SIZE]

You can use the following options with simple axis HTTP server.

     -p PORT port number to use, default port is 9090
     -r REPO_PATH repository path, default is ../
     -t TIMEOUT socket read timeout, default is 30 seconds
     -l LOG_LEVEL log level, available log levels:
     0 - critical 1 - errors 2 - warnings
     3 - information 4 - debug 5- user 6 - trace
     Default log level is 4(debug).
     -f LOG_FILE log file, default is %WSFCPP_HOME%\logs\axis2.log
     or axis2.log in current folder if WSFCPP_HOME not set
     -s LOG_FILE_SIZE Maximum log file size in mega bytes, default maximum size is 1MB.
     -h display the help screen.

Example :

     axis2_http_server.exe -l 3 -p 8080 -r %WSFCPP_HOME% -f C:\logs\error.log

## 11. Deploying with Apache HTTP Server Version 2.x

### 11.1 Linux Platform

To build Axis2/C with the Apache HTTP server module, also called mod_axis2, you need to provide the following configuration options on the Linux platform:

    ./configure --with-apache2=[path to Apache2 include directory] [other configure options]

NOTE: Some Apache2 distributions, specially development versions, install APR (Apache Portable Run-time) include files in a separate location. In that case, to build mod_axis2, use:

    ./configure --with-apache2=[path to Apache2 include directory] --with-apr=[path to APR include directory]
     [other configure options]

Then build the source tree as usual using:

     make
     make install

This will install mod_axis2.so into your AXIS2C_INSTALL_DIR/lib folder.

### 11.2 MS Windows Platform

On the MS Windows platform, you have to provide the Apache2 install location in the configure.in file with the setting APACHE_BIN_DIR. Example:

    APACHE_BIN_DIR = "C:\Program Files\Apache Software Foundation\Apache2.2"

Based on the Apache HTTP server version you are using, you also need to set the setting APACHE_VERSION_2_0_X in the configure.in file. If you are using Apache 2.2 family, this setting should be set to 0,else set it to 1.

    APACHE_VERSION_2_0_X = 0

To build the source, you have to run the command

    nmake axis2_apache_module

This will build mod_axis2.dll and copy it to AXIS2C_INSTALL_DIR\lib directory.

### 11.3 Deploying mod_axis2

NOTE: To execute some of the commands given below, you might require super user privileges on your machine. If you are using the binary release of Axis2/C, please note that it is built with Apache 2.2.

Copy the mod_axis2 shared library (libmod_axis2.so.0.6.0 on Linux and mod_axis2.dll on MS Windows) to the Apache2 modules directory as mod_axis2.so

On Linux

    	cp $WSFCPP_HOME/lib/libmod_axis2.so.0.6.0 /usr/lib/apache2/modules/mod_axis2.so

On MS Windows

    	copy /Y "%WSFCPP_HOME%\lib\mod_axis2.dll" C:\Apache2\modules\mod_axis2.so

Edit the Apache2's configuration file (generally httpd.conf) and add the following directives at the end of the file.

    LoadModule axis2_module MOD_AXIS2_SO_PATH
    Axis2RepoPath AXIS2C_INSTALL_DIR
    Axis2LogFile PATH_TO_LOG_FILE
    Axis2LogLevel LOG_LEVEL
    Axis2ServiceURLPrefix PREFIX
    Axis2MaxLogFileSize SIZE_IN_MB
    <Location /axis2>
     SetHandler axis2_module
    </Location>

Please note that you have to fine tune the above settings to mach your system.
MOD_AXIS2_SO_PATH has to be replaced with the full path to mod_axis2.so, for example, `/usr/lib/apache2/modules/mod_axis2.so` on Linux, or `C:\Apache2\modules\mod_axis2.so` on MS Windows
AXIS2C_INSTALL_DIR has to be replaced with the full path to Axis2/C repository, for example, `/usr/local/axis2` on Linux, or `c:\axis2c` on MS Windows. Note that repository path should have read access to the daemon user account under which the Apache2 HTTPD process is run.
PATH_TO_LOG_FILE has to be replaced with the full path to where you wish to have the Axis2/C log file, for example, `/tmp/axis2.log` on Linux, or `C:\Apache2\logs\axis2.log` on MS Windows. Note that the log file path should have write access to the daemon user account under which the Apache2 HTTPD process is run.
LOG_LEVEL has to be replaced with one of the following values: crit, error, warn, info, debug, trace. These log levels have the following meanings:

- crit - log critical errors
- error - log errors and above
- warn - log warnings and above
- info - log information and above
- debug - log debug information and above, this is the default log level used
- user - log user level messages and above
- trace - log trace messages and above

SIZE_IN_MB must be replaced by the size of the particular resource in MB, rounded to the nearest whole value.
PREFIX has to be replaced with the prefix to be used with the service endpoints. This is optional and defaults to "services". As an example, if you have "web_services" as the prefix, then all the services hosted would have the endpoint prefix of :
http://localhost/axis2/web_services
If you wish, you can also change the location as well by replacing "/axis2" in <Location /axis2> setting with whatever you wish.

NOTE: If you want to use a Shared Global Pool with Apache you have to give another entry called Axis2GlobalPoolSize.You have to give the size of the shared global pool in MB.If you doesn't set the value or if you set a negative value Apache module doesn't create shared global pool.

    Axis2GlobalPoolSize SIZE_IN_MB

To ensure that everything works fine, start Apache2 (restart if it is already running) and test whether the mod_axis2 module is loaded correctly by accessing the URL: http://localhost/axis2/services.

This should show the list of services deployed with Axis2/C. Then you should be able to run clients against this endpoint. Example:

    echo http://localhost/axis2/services/echo

In case things are not working as expected, here are some tips on how to troubleshoot:

- Double check the steps you followed in installing and configuring mod_axis2. Check if the locations given in httpd.conf are correct, and also check the folder permissions.
- Have a look at the axis2.log file for clues as to what is going wrong. You can set the log level to debug, user or trace to gather more information
- In case the axis2.log file is not written at all, there is a good chance that mod_axis2 is crashing. You can have a look at the error.log file of Apache2 to get an idea on what is going wrong. This file is usually placed in the APACHE_INSTALL_DIR/logs folder.

## 12. Deploying with Microsoft IIS Server

Use the Axis2/C VC project or makefile to buid the component. If you are using the makefile to build the source, you have to run the command

    nmake axis2_iis_module

In this document I assume that the mod_axis2_IIS.dll is in the directory `c:\axis2c\lib` and WSFCPP_HOME is `c:\axis2c`

Add the following key to the registery.

`HKEY_LOCAL_MACHINE\SOFTWARE\Apache Axis2c\IIS ISAPI Redirector`

Add a string value with the name `WSFCPP_HOME` and a value of `c:\axis2c`

Add a string value with the name `log_file` and a value of `c:\axis2c\logs\axis2.log`

Add a string value with the name `log_level`. The value can be either `trace`, `error`, `info`, `critical`, `user`, `debug`, or `warning`.

You can add a string value with the name `services_url_prefix`. This is optional and defaults to "/services". As an example, if you have "/web_services" as the prefix, then all the services hosted would have the endpoint prefix of :
http://localhost/axis2/web_services.
Note: don't forget the / at the begining.

If you wish, you can also change the location as well by adding a string value with the name `axis2_location`. This is also optional and defaults to /axis2. If you have /myserser as the value you can access your web services with a url like http://localhost/myserver/services.
Note: Don't forget the / at the beginning.

Now you can do all the registry editing using the JScript file axis2_iis_regedit.js provided with the distribution. When you build axis2/C with the IIS module the file is copied to the root directory of the binary distribution. Just double click it and everything will be set to the defaults. The axis2c_home is taken as the current directory, so make sure you run the file in the Axis2/C repository location (or root of the binary distribution). If you want to change the values you can manually edit the the .js file or give it as command line arguments to the script when running the script. To run the jscript from the command line use the command `:\cscript axis2_iis_regedit.js optional arguments`. We recomend the manual editing as it is the easiest way to specify the values.

IIS 5.1 or Below

Using the IIS management console, add a new virtual directory to your IIS/PWS web site. The name of the virtual directory must be `axis2`. Its physical path should be the directory in which you placed mod_axis2_IIS.dll (in our example it is c:\axis2c\lib). When creating this new virtual directory, assign execute access to it.

By using the IIS management console, add mod_axis2_IIS.dll as a filter in your IIS/PWS web site and restart the IIS admin service.

IIS 6 & 7

Using the IIS management console, add the mod_axis2_IIS.dll as a Wildcard Script Map.

- Executable should be the complete path to the mod_axis2_IIS.dll
- You can put any name as the name of the Wildcard Script Map

Please don't add the mod_axis2_IIS.dll as a filter to IIS as in the IIS 5.1 case.

Note: If the Axis2/C failed to load, verify that Axis2/C and its dependent DLLs are in the System Path (not the user path).

## 13. Using SSL Client

### 13.1 Building and Configuring the Client

In order to allow an Axis2/C client to communicate with an SSL enabled server, we need to compile Axis2/C with SSL support enabled.

To build with SSL client support, first of all, make sure you have installed OpenSSL on your machine. Then you can start building with SSL client support. This can be achieved on Linux by configuring Axis2/C with the `--enable-openssl=yes` option.

Example `
%./configure --enable-openssl=yes --prefix=${WSFCPP_HOME}/deploy
%make
%make install
`

On MS Windows, set `ENABLE_SSL=1` in the `configure.in` file and run the `nmake all` command.

### 13.1.1 Creating the Client Certificate Chain File

If you need SSL client authentication, Axis2/C requires you to provide the client certificate and the private key file in a single file. Such a file which contains both the certificate and relevant private key is called a certificate chain file. Creating such a file is very easy. Assume that the client certificate is stored in a file named `client.crt` and the private key is stored in a file named `client.key`. Then the certificate chain file can be created by concatenating the certificate file and the private key file in that order, in to another file, say `client.pem`.

On Linux you can do this as follows: `%cat client.crt client.key > client.pem`

On MS Windows, you can do this by copying the contents of client.crt and client.key files and saving them in a file named client.pem using Notepad.

### 13.1.2 Configuration

Uncomment the following in `axis2.xml` to enable https transport receiver and https transport sender. Axis2/C will then be able to recognize the "https" sheme in a given end point reference (EPR) and use SSL transport.

    <transportReceiver name="https" class="axis2_http_receiver">
     <parameter name="port" locked="false">6060</parameter>
     <parameter name="exposeHeaders" locked="true">false</parameter>
    </transportReceiver>

    <transportSender name="https" class="axis2_http_sender">
     <parameter name="PROTOCOL" locked="false">HTTP/1.1</parameter>
    </transportSender>

For the SSL client to work, the file containing the CA certificate should be given as `SERVER_CERT` parameter in the axis2.xml file. If you need client authentication, you can also set the parameters in the axis2.xml file to specify the client certificate, private key, and the passphrase for the client private key. Parameter names for these are:

`KEY_FILE` - certificate chain file containing the client's certificate and the private key (Please refer to the creating the client certificate chain file section)
`SSL_PASSPHRASE` - passphrase used to encrypt the private key file.

Example:

`<parameter name="SERVER_CERT">/path/to/ca/certificate</parameter>`
`<parameter name="KEY_FILE">/path/to/client/certificate/chain/file</parameter>`
`<```parameter name="SSL_`PASSPHRASE">passphrase</parameter>`

For testing purposes, you can use the server's certificate instead of the CA certificate. You can obtain this by running the command `openssl s_client -connect <servername>:<port>` and copying the portion of the output bounded by and including:

    -----BEGIN CERTIFICATE-----
    -----END CERTIFICATE-----

On Linux, if you run the following piece of code, the server certificate will be saved to a file `cert.pem`:

    echo |\
    openssl s_client -connect <servername>:<port> 2>&1 |\
    sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' > cert.pem

NOTE: Instead of setting these parameters in the `axis2.xml` file, you can also set these parameters programmatically in your client code.

### 13.2 Configuring the Server

Here we will only look at the configuration of the Apache HTTP Web server. Refer to the 'Deploying with Apache HTTP Server Version2.x' section for information on deploying Axis2/C as an Apache module.

For more detailed information on SSL configuration, please refer to Apache2 SSL/TLS documentation.

In the `httpd.conf` file, add the following configuration statements (in addition to other necessary configuration):

`SSLEngine on
SSLCertificateFile /path/to/server/certificate/file
SSLCertificateKeyFile /path/to/private/key/file
SSLCACertificateFile /path/to/CA/certificate/file
SSLVerifyClient require
SSLVerifyDepth 1`

NOTE: The last two lines, `SSLVerifyClient` and `SSLVerifyDepth` are only needed when you need client authentication.

## 14. Using Proxy Support

When using a proxy, there are two methods for specifying proxy settings:

1. Specify proxy settings in axis2.xml
2. Provide proxy settings using service client API

### 14.1 Specifying Proxy Settings in axis2.xml

    <transportSender name="http" class="axis2_http_sender">
     <parameter name="PROTOCOL" locked="false">HTTP/1.1</parameter>
     <parameter name="PROXY" proxy_host="127.0.0.1" proxy_port="8080" locked="true"/>
    </transportSender>

### 14.2 Providing Proxy Settings Using Service Client API

You can specify proxy settings using the following function with the service client:

    axis2_svc_client_set_proxy(axis2_svc_client_t *svc_client,
     const axutil_env_t *env,
     axis2_char_t *proxy_host,
     axis2_char_t *proxy_port);

## 15. Using Proxy Authentication Support

When using proxy authentication, there are three methods for specifying proxy authentication settings:

1. Specify proxy settings with authentication in axis2.xml
2. Provide proxy settings with authentication using service client API
3. Provide proxy authentication settings using service client options

### 15.1 Specifying Proxy Settings with Authentication in axis2.xml

    <transportSender name="http" class="axis2_http_sender">
     <parameter name="PROTOCOL" locked="false">HTTP/1.1</parameter>
     <parameter name="PROXY" proxy_host="127.0.0.1" proxy_port="8080" proxy_username="" proxy_password="" locked="true"/>
    </transportSender>

### 15.2 Providing Proxy Settings with Authentication Using Service Client API

You can specify proxy authentication settings using the following function with the service client:

    axis2_svc_client_set_proxy_with_auth(axis2_svc_client_t *svc_client,
     const axutil_env_t *env,
     axis2_char_t *proxy_host,
     axis2_char_t *proxy_port,
     axis2_char_t *username,
     axis2_char_t *password);

### 15.3 Providing Proxy Authentication Settings Using Service Client Options

You can specify proxy authentication settings using the following function with the service client options:

    axis2_options_set_proxy_auth_info(
     axis2_options_t * options,
     const axutil_env_t * env,
     const axis2_char_t * username,
     const axis2_char_t * password,
     const axis2_char_t * auth_type);

In `auth_type`, use Basic to force Basic Authentication or Digest to force Digest Authentication. Leave this field NULL if you are not forcing authentication.

### 15.4 Predetermining Proxy Authentication Details

You can also predetermine whether proxy authentication is required. This can be done by calling the function below:

    axis2_options_set_test_proxy_auth(
     axis2_options_t * options,
     const axutil_env_t * env,
     const axis2_bool_t test_proxy_auth);

Set `test_proxy_auth` to `AXIS2_TRUE` to enable testing.When testing is enabled, the request will be sent without without adding authentication information. If it fails, and requests Authentication Information, the request type of authentication will be saved. This information can be obtained in the following manner:

    axis2_svc_client_get_auth_type(
     const axis2_svc_client_t * svc_client,
     const axutil_env_t * env);

This will return either Basic, Digest or NULL according to the type of authentiation requested. In addition to that, after each request made through the service client, you can check whether authentication was required.

    axis2_svc_client_get_proxy_auth_required(
     const axis2_svc_client_t * svc_client,
     const axutil_env_t * env);

Please take a look at the `echo_blocking_auth` sample for more information on how to use these methods to identify proxy Authentication requirements.

## 16. Using HTTP Authentication Support

When using HTTP authentication, there are two methods for specifying proxy authentication settings:

1. Specify HTTP authentication settings in axis2.xml
2. Provide HTTP authentication settings using service client options

### 16.1 Specifying HTTP Authentication Settings in axis2.xml

    <transportSender name="http" class="axis2_http_sender">
     <parameter name="PROTOCOL" locked="false">HTTP/1.1</parameter>
     <parameter name="HTTP-Authentication" username="your username" password="your password" locked="true"/>
    </transportSender>

### 16.2 Providing HTTP Authentication Settings Using Service Client Options

You can specify HTTP authentication settings using the following function with the service client options:

    axis2_options_set_http_auth_info(
     axis2_options_t * options,
     const axutil_env_t * env,
     const axis2_char_t * username,
     const axis2_char_t * password,
     const axis2_char_t * auth_type);

In `auth_type`, use Basic to force HTTP Basic Authentication or Digest to force HTTP Digest Authentication. Leave this field NULL if you are not forcing authentication.

### 16.3 Predetermining HTTP Authentication Details

You can also predetermine whether HTTP authentication is required. This can be done by calling the function below:

    axis2_options_set_test_http_auth(
     axis2_options_t * options,
     const axutil_env_t * env,
     const axis2_bool_t test_http_auth);

Set `test_http_auth` to `AXIS2_TRUE` to enable testing.When testing is enabled, the request will be sent without without adding authentication information. If it fails, and requests Authentication Information, the request type of authentication will be saved. This information can be obtained in the following manner:

    axis2_svc_client_get_auth_type(
     const axis2_svc_client_t * svc_client,
     const axutil_env_t * env);

This will return either Basic, Digest or NULL according to the type of authentiation requested. In addition to that, after each request made through the service client, you can check whether authentication was required.

    axis2_svc_client_get_http_auth_required(
     const axis2_svc_client_t * svc_client,
     const axutil_env_t * env);

Please take a look at the `echo_blocking_auth` sample for more information on how to use these methods to identify HTTP Authentication requirements.

## 17. WSDL2C Tool

WSDL2C tool that comes with Axis2/Java supports the generation of Axis2/C stubs and skeletons for WSDL files. This is a Java tool that can be used to generate C code that works with Axis2/C API. You should use Axis2/Java SVN revision 529533 or later revisions. You can download the Axis2/Java nightly build and use those binaries to generate code. Check out a basic guide on the Java tool.

Before you run the tool, make sure that all the .jar library files that come with Axis2/Java are added to the CLASSPATH environment variable.

### 17.1 Generating Service Skeletons

The tool can be run with the following parameters and generate the service skeleton and other required files with ADB (Axis Data Binding) support.

    java org.apache.axis2.wsdl.WSDL2C -uri interoptestdoclitparameters.wsdl -ss -sd -d adb -u

To understand the meanings of the options used with the tool, please have a look at the Java tool documentation.

If you need an XML in/out programming model, you can just ignore the data binding support. To generate code with no data binding support, just replace `-d adb -u`, that was used in a previous command, with `-d none`.

    java org.apache.axis2.wsdl.WSDL2C -uri interoptestdoclitparameters.wsdl -ss -sd -d none

The WSDL file, `interoptestdoclitparameters.wsdl`, used in the above command examples can be found in <axis2_src_dir>/test/resources directory.

Once the code is generated, you have to implement the business logic for the service. For this, locate the skeleton source file from the generated files. To identify the locations where you can place your business logic in line with the operations defined in the WSDL file that you used to generate code, look for the comment lines:

    /* Todo fill this with the necessary business logic */

You can also go through the generated header files and understand the API in line with the WSDL file that you used to generate the code.

### 17.2 Generating Client Stubs

The WSDL2C code generator tool provides support for generating client stubs as well. You can generate the required stubs from a given WSDL with the other supporting files. Use following parameters to generate the Axis2/C client stub code with ADB support.

    java WSDL2C -uri interoptestdoclitparameters.wsdl -d adb -u

In order to ignore the data binding support and use a raw XML in/out model, just use the following parameters.

    java WSDL2C -uri interoptestdoclitparameters.wsdl -d none

Like in the case of service skeletons, you have to fill in the business logic as required in the client stubs as well. To do this, go through the header files generated and understand the API in line with the WSDL file that you used to generate the code.

## 18. TCP Transport

### 18.1 Building AXIS2C enabling TCP

This section will guide you through installing Axis2C with tcp enabled, and this also includes how to test it by running samples. Please note that both the Server and the Client must be built with TCP enabled.

### 18.1.1 Linux Based Systems

1. When you are installing, you have to use the configure command with the option to enable tcp by providing the following argument:

    	./configure --enable-tcp=yes
    	make
    	make install

2. Then to confirm that you have successfully built the source with tcp enabled you can check in your $WSFCPP_HOME/lib folder for following files:

    	libaxis2_tcp_sender.so
    	libaxis2_tcp_reciever.so

3. To setup the tcp transport sender, you have to edit the axis2.xml by uncommenting following entry:

    	<transportSender name="tcp" class="axis2_tcp_sender">
     <parameter name="PROTOCOL" locked="false">TCP</parameter>
     </transportSender>

### 18.1.2 MS Windows Based Systems

1. When you are installing, you have to set the configure option to enable tcp by specifying in `configure.in`:

     WITH_TCP = 1

2. Then to confirm that you have successfully built the source with tcp enabled you can check in your %WSFCPP_HOME%\lib folder for following files:

    	axis2_tcp_sender.dll
     axis2_tcp_reciever.dll

3. To setup the tcp transport sender, you have to edit the axis2.xml by uncommenting following entry:

     <transportSender name="tcp" class="axis2_tcp_sender">
     <parameter name="PROTOCOL" locked="false">TCP</parameter>
     </transportSender>

### 18.2 Server Side

- To run the tcp server on Linux based systems, you have to start the tcp server which runs in 9091 as its default port.

    	cd $WSFCPP_HOME/bin/
    	./axis2_tcp_server

- To run the tcp server on MS Windows based systems, you have to start the tcp server as,

     cd %WSFCPP_HOME%\bin
     axis2_tcp_server.exe

### 18.2.1 Simple Axis2 TCP Server

Simple Axis2 TCP Server is the inbuilt TCP server of Axis2/C.

### 18.2.1.1 Linux Based Systems

Synopsis :

     axis2_tcp_server [-p PORT] [-t TIMEOUT] [-r REPO_PATH] [-l LOG_LEVEL] [-f LOG_FILE] [-s LOG_FILE_SIZE]

You can use the following options with simple axis TCP server.

     -p PORT port number to use, default port is 9091
     -r REPO_PATH repository path, default is ../
     -t TIMEOUT socket read timeout, default is 30 seconds
     -l LOG_LEVEL log level, available log levels:
     0 - critical 1 - errors 2 - warnings
     3 - information 4 - debug 5- user 6 - trace
     Default log level is 4(debug).
     -f LOG_FILE log file, default is $WSFCPP_HOME/logs/axis2.log
     or axis2.log in current folder if WSFCPP_HOME not set
     -s LOG_FILE_SIZE Maximum log file size in mega bytes, default maximum size is 1MB.
     -h display the help screen.

Example :

     axis2_tcp_server -l 3 -p 8080 -r $WSFCPP_HOME -f /dev/stderr

### 18.2.1.2 MS Windows Based Systems

Synopsis :

     axis2_tcp_server.exe [-p PORT] [-t TIMEOUT] [-r REPO_PATH] [-l LOG_LEVEL] [-f LOG_FILE] [-s LOG_FILE_SIZE]

You can use the following options with simple axis TCP server.

     -p PORT port number to use, default port is 9091
     -r REPO_PATH repository path, default is ../
     -t TIMEOUT socket read timeout, default is 30 seconds
     -l LOG_LEVEL log level, available log levels:
     0 - critical 1 - errors 2 - warnings
     3 - information 4 - debug 5- user 6 - trace
     Default log level is 4(debug).
     -f LOG_FILE log file, default is %WSFCPP_HOME%\logs\axis2.log
     or axis2.log in current folder if WSFCPP_HOME not set
     -s LOG_FILE_SIZE Maximum log file size in mega bytes, default maximum size is 1MB.
     -h display the help screen.

Example :

     axis2_tcp_server.exe -l 3 -p 8080 -r %WSFCPP_HOME% -f C:\logs\error.log

### 18.3 Client Side

- In your service client you have to give the end point address adding tcp as the URI Schema name in the client's code.

    tcp://[service_hostname]:[service_port]/axis2/services/your_service_name

- You can use TCPMon to figure out how the message is transferred (without having it's http headers) after you've built Axis2C enabling tcp.

## 19. AMQP Transport

### 19.1 Building AXIS2C enabling AMQP

This section will guide you through installing Axis2C with AMQP enabled, and this also includes how to test it by running samples. Please note that both the Server and the Client must be built with AMQP enabled.

### 19.1.1 Linux Based Systems

1. When you are installing, you have to use the configure command with the option --with-qpid as follows

     ./configure --with-qpid=path/to/qpid home
     make
     make install

2. Then to confirm that you have successfully built the source with AMQP enabled you can check in your $WSFCPP_HOME/lib folder for following files:

     libaxis2_qmqp_sender.so
     libaxis2_amqp_reciever.so

3. To setup the AMQP transport, you have to edit the axis2.xml and add the following entries:

     <transportReceiver name="amqp" class="axis2_amqp_receiver">
     <parameter name="qpid_broker_ip" locked="false">127.0.0.1</parameter>
     <parameter name="qpid_broker_port" locked="false">5672</parameter>
     </transportReceiver>

     <transportSender name="amqp" class="axis2_amqp_sender"/>

### 19.1.2 MS Windows Based Systems

Axis2/C does not support AMQP transport on Windows.

### 19.2 Server Side

Start the Qpid broker as follows.

    $ cd ${QPID_HOME}/sbin
    $ ./qpidd --data-dir ./

Start the axis2_amqp_server as follows.

    $ cd ${WSFCPP_HOME}/bin
    $ ./axis2_amqp_server

You should see the message
Started Simple Axis2 AMQP Server...
This will connect to the Qpid broker listening on 127.0.0.1:5672.
To see the possible command line options run

    $ ./axis2_amqp_server -h

NOTE : You have the flexibility of starting the Qpid broker first and then axis2_amqp_server or vise versa.

### 19.2.1 Simple Axis2 AMQP Server

Simple Axis2 AMQP Server is the inbuilt AMQP server of Axis2/C.

### 19.2.1.1 Linux Based Systems

Synopsis :

     axis2_amqp_server [-i QPID_BROKER_IP] [-p QPID_BROKER_PORT] [-r REPO_PATH] [-l LOG_LEVEL] [-f LOG_FILE] [-s LOG_FILE_SIZE]

You can use the following options with simple axis AMQP server.

     -i IP where the Qpid broker is running, default IP is 127.0.0.1
     -p PORT port number the Qpid broker listens on, default port is 5672
     -r REPO_PATH repository path, default is ../
     -l LOG_LEVEL log level, available log levels:
     0 - critical
    	1 - errors
    	2 - warnings
     3 - information
    	4 - debug
    	5- user
    	6 - trace
     Default log level is 4(debug).
     -f LOG_FILE log file, default is $WSFCPP_HOME/logs/axis2.log or axis2.log in current folder if WSFCPP_HOME not set
     -s LOG_FILE_SIZE Maximum log file size in mega bytes, default maximum size is 1MB.
     -h display the help screen.

Example :

     axis2_amqp_server -i 127.0.0.1 -p 5050 -r $WSFCPP_HOME -f /dev/stderr

### 19.3 Client Side

When the axis2_amqp_server is up and running, you can run the sample clients in a new shell as follows.

    $ cd ${WSFCPP_HOME}/samples/bin/amqp

    $ ./echo_blocking

This will invoke the echo service.
To see the possible command line options for sample clients run them with '-h' option

## 20. Archive Based Deployment

Axis2/C supports two main deployment models,

1. Directory Based Deployment
2. Archive Based Deployment

Our discussion in this section focuses on how to setup and use archive based deployment in Axis2/C. By default, Axis2/C may be built without enabling archive based deployment. Therefore, first and foremost you will have to most probably rebuild from source.

Also, it is requirement that you have zlib. Most Linux systems do have zlib by default, but would require zlib development packages. More information can be found here. For MS Windows systems, you can download it from here.

Next, you will have to build Axis2/C enabling Archive Based Deployment. On Linux, you need to set the `--with-archive=[path_to_zlib_headers]`

Example: `
%./configure --with-archive=/usr/include/ --prefix=${WSFCPP_HOME}/deploy
%make
%make install
`

On MS Windows, set `WITH_ARCHIVE = 1` in the `configure.in` file and run the `nmake all` command. Please note that you have to specify the directory where you can find the zlib binary, for a MS Windows system. This can be done by setting the `ZLIB_BIN_DIR` in the `configure.in` file.

### 20.1 Deploying Services

Once you have successfully completed the installation, you will have to deploy services as archives in order to make use of this deployment model. Please note that directory based deployment can coexist with the archive based deployment model. Therefore, you can alternatively use either of the two.

You will merely have to add your existing service libraries and the services.xml file into an archive. For example, in order to deploy the sample echo service as an archive, you can zip the echo folder found in the `AXIS2C_BIN_DIR/services` directory. You can optionally rename your zip file, to have the `.aar` extension.

Please note that all such services deployed as archives should also be placed inside the `AXIS2C_BIN_DIR/services` directory. Now, when ever you start your Simple Axis2 Server, or any Axis2/C module attached to any other server, your services deployed as archives, will also get loaded.

### 20.2 Deploying Modules

Similar to services, you also can deploy modules as archives. You also can optionally rename your zip files to have the extension, `.mar` as in service archives.

Your module archives must be placed in the `AXIS2C_BIN_DIR/modules` directory.

### 20.3 Known Issues

Please note that there are a few known issues when running archive based deployment, mainly on Linux based systems.

- If you want to run both client and server from same respository, assign super-user privilideges for your server in order to prevent un-zipped files getting overwritten, which will in return cause a segmentation fault on your server.

- Please make sure that the application you choose to create archives preserves executable rights, and symbolic links of libraries that are found inside the archive, once unzipped.

## 21. TCPMon Tool

TCPMon is a TCP Monitor tool provided by Axis2/C for monitoring payloads exchanged between client and server. If you are using a source distribution, this may or may not be built for you by default. Thus, to get started, you may require building it from source.

On Linux

    	./configure --prefix=${WSFCPP_HOME} --enable-tests=no
    	make

On MS Windows

    	nmake tcpmon

Please note that in most Linux based installations, this will most probably be built for you. Once you've done with the building process, you can find the executable at `${WSFCPP_HOME}/bin/tools` on Linux, or at `%WSFCPP_HOME%\bin\tools` on MS Windows.

By default, the TCPMon tool will listen on port `9090` and reply to port `8080`. The default target host will be `localhost` and `tcpmon_traffic.log` will be the default log_file. If you want to change any of these settings run ./`tcpmon -h` on Linux, or `tcpmon.exe -h` on MS Windows for more information.

The TCPMon tool does depend on the Axis2/C Util, Axis2/C AXIOM and Axis2/C Parser libraries. Thus, if you want to use TCPMon to monitor payloads in any other message transfer, independant of the Axis2/C engine, you will have to build those dependant libraries too. In addition to that, TCPMon does not depend on the Axis2/C Core and installing the Axis2/C engine is not always a pre-requisite to run TCPMon.

## Appendix A - axis2.xml

The axis2.xml file is the configuration file for Axis2/C. It has 6 top level elements. They are parameter, transportReceiver, transportSender, module, phaseOrder and messageReceiver. The following sections describe these elements, their sub elements, element attributes, possible values, and their purpose.

axisconfig is the root element of axis2.xml file.

Attribute | Possible Values
--- | ---
name | Axis2/C

### parameter

In Axis2/C, a parameter is a name value pair. Each and every top level parameter available in the axis2.xml (direct sub elements of the root element) will be stored as parameters as `axis2_conf`. Therefore, the top level parameters set in the configuration file can be accessed via the `axis2_conf` instance in the running system.

Sub elements :- none

Attributes :- name, locked

Attribute | Description
--- | ---
name | Name of the parameter. The table below shows possible values of the name attribute and their description.
Value | Description | Possible Text of Parameter Element
--- | --- | ---
enableMTOM | Enable MTOM support when sending binary attachments | true or false
enableREST | Enable REST support | true or false
locked | Indicates whether the parameter can be changed from the code. Following are the possible values for the locked attribute.
Value | Description
--- | ---
true | The parameter cannot be changed from the code
false | The parameter can be changed from the code.

### transportReceiver

This element specifies the transport receiver details in an IN-OUT message exchange scenario. The users can change the transport receiver port as they wish.

Attributes :- name, class

Attribute | Description | Possible Values
--- | --- | ---
name | Specifies which transport protocol is used | http (when using HTTP)
class | Specifies the shared library which implements the transport interface | Name of the shared library. Example:- On Linux if the value is given as foo then shared library is libfoo.so. On MS Windows, foo.dll.

Sub elements :- can have zero or more parameter elements.

The following table shows possible parameter values.

Attribute | Description
--- | ---
name | Name of the parameter.
Value | Description | Possible Text of Parameter Element
--- | --- | ---
port | Transport listener port | Integer specifying the port number
exposeHeaders | Whether Transport Headers are exposed to a Service | true/false
locked | whether the parameter can be changed from the code
Value | Description
--- | ---
true | Parameter cannot be changed from the code
false | The parameter can be changed from the code.

### transportSender

This element specifies the transport senders used to send messages.

Attributes :- name, class

Attribute | Description | Possible Values
--- | --- | ---
name | Specifies which transport protocol is used when sending messages | http(when using http)
class | Specifies the shared library which implements the transport interface | Name of the shared library. Example:- On Linux if the value is given as foo then the shared library is libfoo.so. On MS Windows, foo.dll.

Sub elements : can have zero or more parameter elements.

The following table shows possible parameter values.

Attribute | Description
--- | ---
name | The name of the parameter.
Value | Description | Possible text of parameter element
--- | --- | ---
PROTOCOL | Transport protocol used | Protocol version. Example:- HTTP /1.1, HTTP/1.0
locked | Indicates whether the parameter can be changed from the code.
Value | Description
--- | ---
true | The parameter cannot be changed from the code
false | The parameter can be changed from the code.

### module

This element is optional. It is used when a particular module needs to be engaged globally for every service deployed with Axis2/C.

Attributes | Description | Possible Values
--- | --- | ---
ref | The name of the module which is to be engaged globally. | Name of the module. Example : addressing

### phaseOrder

The order of phases in a particular execution chain has to be configured using phaseOrder element.

Attribute | Description | Possible Values
--- | --- | ---
type | The flow to which the phase belongs | inflow outflow INfaultflow Outfaultflow

A flow is a collection of handlers which is invoked for a particular message. The types of flows are described below.

Flow | Description
--- | ---
inflow | Collection of handlers invoked for a message coming in to the system.
outflow | Collection of handlers invoked for a message going out of the system.
INfaultflow | Collection of handlers invoked for an incoming fault message.
Outfaultflow | Collection of handlers invoked for an outgoing fault message.

Sub elements : phase: represents the available phases in the execution chain

The system predefined phases cannot be changed.

The system predefined phases are,

- Transport
- PreDispatch
- Dispatch
- PostDispatch
- MessageOut

Attribute | Description | Possible Values
--- | --- | ---
name | Specifies the name of the phase | Transport, Dispatch, PreDispatch, PostDispatch, MessageOut User defined phases (can have a user defined name)

Sub elements of phase element: handler

Attribute | Description | Possible Values
--- | --- | ---
name | Specifies the handler name. Phase may contain zero or more handlers. | Based on the handler name. Example: AddressingbasedDispatcher, RequestURIbaseddispatcher
class | Specifies the shared library which implements the handler | Name of the shared library. Example: On Linux, if the value is given as foo, then the shared library is libfoo.so. On MS Windows, foo.dll.

### messageReceiver

Attribute | Description | Possible Values
--- | --- | ---
mep | Message Exchange Pattern | IN-OUT, IN-ONLY
class | Specify the shared library which implements the transport interface. If not specified, the Axis2/C default message receiver is used. | Name of the shared library. Example: On Linux, if the value is given as foo, then the shared library is libfoo.so. On MS Windows, foo.dll.

## Appendix B - services.xml

Configuration of a service is specified using a services.xml. Each service or service archive file needs to have a services.xml in order to be a valid service. The following sections describe the elements of the services.xml file.

If services.xml describes a single service, the root element is service. If it is describing a service group, then the root element is serviceGroup. The service element will be a child element of serviceGroup if there are multiple services specified in services.xml.

Attributes | Description | Possible Values
--- | --- | ---
name | Name of the service or service group. | Depends on the service or the service group. Examples: echo, sg_math

This is optional. This element can be used to describe the service in a human readable format.

This is optional. Can be used to engage modules at service level.

Attributes | Description | Possible Values
--- | --- | ---
ref | Name of the module which is to be engaged for the service | Name of the module which is to be engaged at service level.

The service element can have any number of parameters as sub elements.

Attribute | Detail
--- | ---
name |
Description | Possible Value | Parameter Value
--- | --- | ---
Specifies the name of the shared library that holds the service implementation | serviceClass | the service name. Example: echo
Path of static WSDL to be attached with service | wsdl_path | Absolute path or path relative to WSFCPP_HOME/bin
Default HTTP Method used in a REST invocation | defaultRESTMethod | One of GET, POST, HEAD, PUT or DELETE
locked |
Description | Possible Value
--- | ---
Indicates whether the parameter can be changed from the code | true/false

The operations of the service are specified using operation elements.

Attributes | Description | Possible Values
--- | --- | ---
name | name of the operation | Example: echoString
mep | message exchange pattern uri. This is defaulted to in-out MEP. For other MEPs, You need to specify the MEP. | Example: "http://www.w3.org/2004/08/wsdl/in-only"

Sub elements of operation: parameter elements can be present as sub elements. Zero or more parameters may be present.

Attribute | Detail
--- | ---
name |
Description | Possible Value | Parameter Value
--- | --- | ---
WS-Addressing action mapping to the operation | wsamapping | A URL representing the WS-Addressing action corresponding to the operation
REST template mapping to the operation | RESTLocation | A template of the expected URL for the operation, with compulsary parts and optional parts, well defined
HTTP Method used in a REST invocation | RESTMethod | One of GET, POST, HEAD, PUT or DELETE

Also, an operation element can have one or more actionMapping element as sub elements.

Description | Possible Values
--- | ---
Action mapping or an alias to an operation | Example: echoString

An operation specific message receiver is specified from this. This is optional.

Attributes | Description | Possible Values
--- | --- | ---
class | Shared library with the message receiver implementation | Name of the shared library. Example: On Linux, if the value is given as foo, then the shared library is libfoo.so. On MS Windows, foo.dll.

## Appendix C - module.xml

The module.xml file provides the configuration details for a particular module in Axis2/C. The top level element is module.

### module

Attributes | Description | Possible Values
--- | --- | ---
name | Name of the module | Example- addressing
class | Specifies the shared library which implements the module. | Name of the shared library. Example- On Linux, if the value is given as foo, then the shared library is libfoo.so. On MS Windows, foo.dll.

Other elements are child elements of module.

### parameter

Any number of parameters can be present, depending on the module.

Attributes | Description | Possible Values
--- | --- | ---
name | Name of the parameter | Depends on the module
locked | Indicates whether the parameter can be changed from the code | true - cannot be changed false - can be changed

### Description

Describes the behavior of the module. This element is optional and has no attributes or sub elements.

### inflow

Encapsulates details added to the in-flow by the module. Zero or one element is possible and does not have any attributes.

Sub elements of inflow : handler, contains details about the module specific handlers added to a particular flow. Zero or more handlers can be added.

Attributes | Description | Possible Values
--- | --- | ---
name | Name of the handler | Depends on the handlers in the module.
class | Specifies the shared library which implements the handler | Name of the shared library. Example: On Linux, if the value is given as foo, then the shared library is libfoo.so. On MS Windows, foo.dll.

sub elements of handler : order, specifies where to put a handler in a particular phase.

Attribute | Description | Possible Values
--- | --- | ---
phase | The name of the phase the handler belongs to | depends on the handler
phaseLast | Indicates that the handler is the last handler of the phase | true
phaseFirst | Indicates that the handler is the first handler of the phase. | true
before | Handler should be invoked before the handler, which is specified by the before handler | handler name
after | Handler should be invoked after the handler, which is specified by the after handler | handler name

From the above attributes, phase is compulsory. Given below are combinations possible from the other four attributes.

Combination | Description
--- | ---
phaseLast | Indicates that the handler is the last handler of the phase
phasefirst | Indicates that the handler is the first handler of the phase.
before | Handler should be invoked before the handler, which is specified by the before handler
after | Handler should be invoked after the handler, which is specified by the after handler
before & after | Handler should be invoked before the handler specified by the before handler, and after the handler specified by the after handler.

outflow, INfaultflow, OUTfaultflow elements have the same syntax as that of inflow.

### operation

This is used when a module wants to add operations to a service that engages the module.

Attributes | Description | Possible Values
--- | --- | ---
name | Name of the operation (compulsory) | Depends on the module
mep | Message Exchange Pattern | IN-OUT, IN-ONLY

Sub elements of operation : Any number of parameters can be included as sub elements in the operation element.

The messageReceiver parameter specifies the message receiver the message is intended for. If it is not set, the default message receiver is used.

## Appendix D - axis2_options

This section describes various types of options that can be set with `axis2_options`. These options are used by the service client before sending messages.

axis2_options_set_action(options, env, action)

Sets the WS-Addressing action that is to be set in the addressing SOAP headers.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct
const axutil_env_t *env | Pointer to the environment struct
const axis2_char_t *action | Pointer to the action string

axis2_options_set_fault_to(options, env, fault_to)

Sets the end point reference which may receive the message in a case of a SOAP fault.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_endpoint_ref_t *fault_to | Pointer to the endpoint reference struct representing the fault to address.

axis2_options_set_from(options, env, from)

Some services need to know the source from which the message comes. This option sets the from endpoint

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_endpoint_ref_t *from | Pointer to the endpoint reference struct representing the from address.

axis2_options_set_to(options, env, to)

Sets the endpoint reference the message is destined to.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_endpoint_ref_t *to | Pointer to the endpoint reference struct representing the to address.

axis2_options_set_transport_receiver(options, env, receiver)

Sets the transport receiver in an OUT-IN message exchange scenario.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_transport_receiver_t *receiver | Pointer to the transport receiver struct.

axis2_options_set_transport_in(options, env, transport_in)

Sets the transport-in description.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_transport_in_desc_t *transport_in | Pointer to the transport_in struct.

axis2_options_set_transport_in_protocol(options, env, transport_in_protocol)

Sets the transport-in protocol.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const AXIS2_TRANSPORT_ENUMS transport_in_protocol | The value indicating the transport protocol.

axis2_options_set_message_id(options, env, message_id)

Sets the message ID.

Parameter | Description
--- | ---
axis2_options_t *options | The pointer to the options struct.
const axutil_env_t *env | The pointer to the environment struct.
const axis2_char_t *message_id | The message ID string.

axis2_options_set_properties(options, env, properties)

Sets the properties hash map.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_hash_t *properties | Pointer to the properties hash map.

axis2_options_set_property(options, env, key, property)

Sets a property with a given key value.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const axis2_char_t *property_key | The property key string.
const void *property | Pointer to the property to be set.

axis2_options_set_relates_to(options, env, relates_to)

Sets the relates-to message information.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_relates_to_t *relates_to | Pointer to the relates_to struct.

axis2_options_set_reply_to(options, env, reply_to)

Sets the reply-to address, when the client wants a reply to be sent to a different end point.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_endpoint_ref_t *reply_to | Pointer to the endpoint reference struct representing the reply-to address.

axis2_options_set_transport_out(options, env, transport_out)

Sets the transport-out description.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_transport_out_desc_t *transport_out | Pointer to the transport-out description struct.

axis2_options_set_sender_transport(options, env, sender_transport, conf)

Sets the sender transport.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const AXIS2_TRANSPORT_ENUMS sender_transport | The name of the sender transport to be set.
axis2_conf_t *conf | Pointer to the conf struct. It is from the conf that the transport is picked with the given name.

axis2_options_set_soap_version_uri(options, env, soap_version_uri)

Sets the SOAP version URI.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const axis2_char_t *soap_version_uri | URI of the SOAP version to be set.

axis2_options_set_timeout_in_milli_seconds(options, env, timeout_in_milli_seconds)

Sets the time out in milli seconds. This is used in asynchronous message exchange scenarios to specify how long the call back object is to wait for the response.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const long timeout_in_milli_seconds | Timeout in milli seconds.

axis2_options_set_transport_info(options, env, sender_transport, receiver_transport, user_separate_listener)

Sets the transport information. Transport information includes the name of the sender transport, name of the receiver transport, and whether a separate listener is to be used to receive a response.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const AXIS2_TRANSPORT_ENUMS sender_transport | Name of the sender transport to be used.
const AXIS2_TRANSPORT_ENUMS receiver_transport | Name of the receiver transport to be used.
const axis2_bool_t use_separate_listener | bool value indicating whether to use a separate listener or not.

axis2_options_set_use_separate_listener(options, env, use_separate_listener)

Sets the bool value indicating whether to use a separate listener or not. A separate listener is used when the transport is a one-way transport and the message exchange pattern is two way.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const axis2_bool_t use_separate_listener | bool value indicating whether to use a separate listener or not

axis2_options_set_soap_version(options, env, soap_version)

Sets the SOAP version.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const int soap_version | SOAP version, either AXIOM_SOAP11 or AXIOM_SOAP12.

axis2_options_set_enable_mtom(options, env, enable_mtom)

Enable or disable MTOM handling when sending binary attachments.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_bool_t enable_mtom | AXIS2_TRUE if MTOM is to be enabled, else AXIS2_FALSE

axis2_options_set_enable_rest(options, env, enable_rest)

Enable or disable REST support.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
axis2_bool_t enable_rest | AXIS2_TRUE if REST is to be enabled, else AXIS2_FALSE

axis2_options_set_http_auth_info(options, env, username, password, auth_type)

Sets HTTP Authentication information.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const axis2_char_t *username | String representing username
const axis2_char_t *password | String representing password.
const axis2_char_t *auth_type | use "Basic" to force basic authentication and "Digest" to force digest authentication or NULL for not forcing authentication

axis2_options_set_proxy_auth_info(options, env, username, password, auth_type)

Sets Proxy Authentication information.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const axis2_char_t *username | String representing username
const axis2_char_t *password | String representing password.
const axis2_char_t *auth_type | use "Basic" to force basic authentication and "Digest" to force digest authentication or NULL for not forcing authentication

axis2_options_set_test_http_auth(options, env, test_http_auth)

Enables testing of HTTP Authentication information.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const axis2_bool_t test_http_auth | bool value indicating whether to test or not, AXIS2_TRUE to enable, AXIS2_FALSE to disable

axis2_options_set_test_proxy_auth(options, env, test_proxy_auth)

Enables testing of proxy Authentication information.

Parameter | Description
--- | ---
axis2_options_t *options | Pointer to the options struct.
const axutil_env_t *env | Pointer to the environment struct.
const axis2_bool_t test_proxy_auth | bool value indicating whether to test or not, AXIS2_TRUE to enable, AXIS2_FALSE to disable