November 24th, 2008Sending Binary with Apache Axis2/C ADB
Axis2/C ADB is a C language binding to the XML schema. ADB object model represents an XML specific to a given schema in a WSDL. You can use the Axis2 codegen tool to generate ADB codes for your WSDL and use that to build and parse your XMLs. The idea is, if you use ADB to build and parse your xmls, it will be really easy to do that and you don’t need to know or understand anything about the schema or the wsdl.
Apache Axis2/C to can be used to send and receive binaries as MTOM, SWA or base64 encoded. But ADB generated code still support to send and receive base64 encoded binaries only. So if you use contract first approach with Axis2/C (i.e start with the WSDL, then write the service based on that), you have to use base64-encoded (non-optimized) as the binary transferring method. Note that you can use the other methods like MTOM or SWA, if you write the code to build and parse the xmls from AXIOM which is a general model for XML like DOM.
Say you have an element with base64Binary type in your request XML. So the schema for that element would be,
<xs:complexType name="Person"> <xs:sequence> <xs:element name="image" type="xs:base64Binary"/> ... <!-- some more elements --> </xs:sequence> </xs:complexType>
After you code generated, you will get the adb_person.h and adb_person.c files with the following function prototypes and the implementations,
/** * Constructor for creating adb_Person_t * @param env pointer to environment struct * @return newly created adb_Person_t object */ adb_Person_t* AXIS2_CALL adb_Person_create( const axutil_env_t *env ); /** * Free adb_Person_t object * @param _Person adb_Person_t object to free * @param env pointer to environment struct * @return AXIS2_SUCCESS on success, else AXIS2_FAILURE */ axis2_status_t AXIS2_CALL adb_Person_free ( adb_Person_t* _Person, const axutil_env_t *env); /** * Getter for image. * @param _Person adb_Person_t object * @param env pointer to environment struct * @return axutil_base64_binary_t* */ axutil_base64_binary_t* AXIS2_CALL adb_Person_get_image( adb_Person_t* _Person, const axutil_env_t *env); /** * Setter for image. * @param _Person adb_Person_t object * @param env pointer to environment struct * @param arg_image axutil_base64_binary_t* * @return AXIS2_SUCCESS on success, else AXIS2_FAILURE */ axis2_status_t AXIS2_CALL adb_Person_set_image( adb_Person_t* _Person, const axutil_env_t *env, axutil_base64_binary_t* arg_image);
So you can manipulate the person element in c language using the create, get, set and free function.
/* here the env is the axutil_env_t* instance - the axis2/c environment */ FILE *f = fopen("./images/person.png", "r+"); int binary_count; /* binary read a function you may write to read the binary data to the variable binary and the count to the variable binary_count */ unsigned char *binary = binary_read(f, env, &binary_count); axutil_base64_binary_t *base64 = axutil_base64_binary_create_with_plain_binary( env, binary, binary_count); adb_Person_t *person = adb_Person_create(env); adb_Person_set_image(person, env, base64);
You can set this adb person directly to your request or to a setter of another adb instance to complete the ADB tree. So this way you can send binaries (as base64 encoded) using the Axis2/C ADB generated code.