This document will describe how to use Axis2 functionality to send/receive binary data with SOAP.
Despite the flexibility, interoperability and global acceptance of XML,
there are times when serializing data into XML does not make sense. Web
services users may need to transmit binary attachments of various sorts like
images, drawings, xml docs, etc together with SOAP message. Such data are
often in a particular binary format.
Traditionally, two techniques have been used in dealing with opaque data in XML;
Sending binary data by value is achieved by embedding opaque data (of course after some form of encoding) as element or attribute content of the XML component of data. The main advantage of this technique is that it gives applications the ability to process and describe data, based and looking only on XML component of the data.
XML supports opaque data as content through the use of either base64 or hexadecimal text encoding. Both these techniques bloat the size of the data. For UTF-8 underlying text encoding, base64 encoding increases the size of the binary data by a factor of 1.33x of the original size, while hexadecimal encoding expands data by a factor of 2x. Above factors will be doubled if UTF-16 text encoding is used. Also of concern is the overhead in processing costs (both real and perceived) for these formats, especially when decoding back into raw binary.
Sending binary data by reference is achieved by attaching pure binary data as external unparsed general entities outside of the XML document and then embedding reference URI's to those entities as elements or attribute values. This prevents the unnecessary bloating of data and wasting of processing power. The primary obstacle for using these unparsed entities is their heavy reliance on DTDs, which impedes modularity as well as use of XML namespaces.
There were several specifications introduced in the Web services world to deal with this binary attachment problem using the "by reference" technique. SOAP with Attachments is one such example. Since SOAP prohibits document type declarations (DTD) in messages, this leads to the problem of not representing data as part of the message infoset, creating two data models. This scenario is like sending attachments with an e-mail message. Even though those attachments are related to the message content they are not inside the message. This causes the technologies for processing and description of data based on XML component of the data, to malfunction. One example is WS-Security.
MTOM (SOAP Message Transmission Optimization Mechanism) is another specification which focuses on solving the "Attachments" problem. MTOM tries to leverage the advantages of the above two techniques by trying to merge the two techniques. MTOM is actually a "by reference" method. Wire format of a MTOM optimized message is same as the Soap with Attachments message, which also makes it backward compatible with SwA endpoints. The most notable feature of MTOM is the use of XOP:Include element, which is defined in XML Binary Optimized Packaging (XOP) specification to reference the binary attachments (external unparsed general entities) of the message. With the use of this exclusive element the attached binary content logically become inline (by value) with the SOAP document even though actually it is attached separately. This merges the two realms by making it possible to work only with one data model. This allows the applications to process and describe by only looking at XML part making reliance on DTDs obsolete. On a lighter note, MTOM has standardized the referencing mechanism of SwA. The following is an extract from the XOP specification.
At the conceptual level, this binary data can be thought of as being base64-encoded in the XML Document. As this conceptual form might be needed during some processing of the XML Document (e.g., for signing the XML document), it is necessary to have a one-to-one correspondence between XML Infosets and XOP Packages. Therefore, the conceptual representation of such binary data is as if it were base64-encoded, using the canonical lexical form of XML Schema base64Binary datatype (see [XML Schema Part 2: Datatypes Second Edition] 3.2.16 base64Binary). In the reverse direction, XOP is capable of optimizing only base64-encoded Infoset data that is in the canonical lexical form.
Apache Axis2 supports Base64 encoding, SOAP with Attachments & MTOM (SOAP Message Transmission Optimization Mechanism).
AXIOM is (and may be the first) Object Model which has the ability to hold binary data. It has been given this ability by allowing OMText to hold raw binary content in the form of javax.activation.DataHandler. OMText has been chosen for this purpose with two reasons. One is that XOP (MTOM) is capable of optimizing only base64-encoded Infoset data that is in the canonical lexical form of XML Schema base64Binary datatype. Other one is to preserve the infoset in both sender and receiver (To store the binary content in the same kind of object regardless of whether it is optimized or not).
MTOM allows to selectively encode portions of the message, which allows us to send base64encoded data as well as externally attached raw binary data referenced by "XOP" element (optimized content) to be send in a SOAP message. User can specify whether an OMText node which contains raw binary data or base64encoded binary data is qualified to be optimized or not at the construction time of that node or later. To take the optimum efficiency of MTOM a user is advised to send smaller binary attachments using base64encoding (None optimized) and larger attachments as optimized content.
OMElement imageElement = fac.createOMElement("image", omNs);
// Creating the Data Handler for the file. Any implementation of
// javax.activation.DataSource interface can fit here.
javax.activation.DataHandler dataHandler = new javax.activation.DataHandler(new FileDataSource("SomeFile"));
DataHandler dataHandler = new DataHandler(dataSource);
//create an OMText node with the above DataHandler and set optimized to true
OMText textData = fac.createOMText(dataHandler, true);
imageElement.addChild(textData);
//User can set optimized to false by using the following
//textData.doOptimize(false);
Also a user can create an optimizable binary content node using a base64 encoded string, which contains encoded binary content, given with the mime type of the actual binary representation.
String base64String = "some_base64_encoded_string";
OMText binaryNode =fac.createOMText(base64String,"image/jpg",true);
Axis2 uses javax.activation.DataHandler to handle the binary data. All optimized binary content nodes will be serialized as Base64 Strings if "MTOM is not enabled". One can also create binary content nodes which will not be optimized at any case. They will be serialized and send as Base64 Strings.
//create an OMText node with the above DataHandler and set "optimized" to false
//This data will be send as Base64 encoded string regardless of MTOM is enabled or not
javax.activation.DataHandler dataHandler = new javax.activation.DataHandler(new FileDataSource("SomeFile"));
OMText textData = fac.createOMText(dataHandler, false);
image.addChild(textData);
Set the "enableMTOM" property in the Options to true, when sending messages.
ServiceClient serviceClient = new ServiceClient ();
Options options = new Options();
options.setTo(targetEPR);
options.setProperty(Constants.Configuration.ENABLE_MTOM, Constants.VALUE_TRUE);
serviceClient .setOptions(options);
When this property is set to true any SOAP envelope, regardless whether it contains optimizable content or not, will be serialized as a MTOM optimized MIME message.
Axis2 serializes all binary content nodes as Base64 encoded strings regardless of they are qualified to be optimize or not, if,
User does not have to specify anything in order for Axis2 to receive MTOM optimised messages. Axis2 will automatically identify and de-serialize accordingly as and when a MTOM message arrives.
Axis 2 server automatically identifies incoming MTOM optimized messages based on the content-type and de-serializes accordingly. User can enableMTOM in the server side for outgoing messages,
To enableMTOM globally for all services users can set the "enableMTOM" parameter to true in the Axis2.xml. When it is set, all outgoing messages will be serialized and send as MTOM optimized MIME messages. If it is not set all the binary data in binary content nodes will be serialized as Base64 encoded strings. This configuration can be overriden in services.xml for per service and per operation basis.
<parameter name="enableMTOM" locked="false">true</parameter>
User must restart the server after setting this parameter.
public class MTOMService {
public void uploadFileUsingMTOM(OMElement element) throws Exception {
OMText binaryNode = (OMText) (element.getFirstElement()).getFirstOMChild();
DataHandler actualDH;
actualDH = (DataHandler) binaryNode.getDataHandler();
... Do whatever you need with the DataHandler ...
}
}
ServiceClient sender = new ServiceClient();
Options options = new Options();
options.setTo(targetEPR);
// enabling MTOM
options.set(Constants.Configuration.ENABLE_MTOM, Constants.VALUE_TRUE);
............
OMElement result = sender.sendReceive(payload);
OMElement ele = result.getFirstElement();
OMText binaryNode = (OMText) ele.getFirstOMChild();
// Retrieving the DataHandler & then do whatever the processing to the data
DataHandler actualDH;
actualDH = binaryNode.getDataHandler();
.............
You can defining a binary element in the schema using the schema type="xsd:base64Binary". Having an element with the type "xsd:base64Binary" is enough for the Axis2 code generators to identify possible MTOM attachments and to generate code accordingly.
Going a little bit further you can use the xmime schema (http://www.w3.org/2005/05/xmlmime) to describe the binary content more precisely. With xmime schema you can indicate the type of content in the element at runtime using an MTOM attribute extension, xmime:contentType. Furthermore, you can identify what type of data might be expected in the element using the xmime:expectedContentType. Putting it all together, our example element becomes:
<element name="MyBinaryData" xmime:expectedContentTypes='image/jpeg' >
<complexType>
<simpleContent>
<extension base="base64Binary" >
<attribute ref="xmime:contentType" use="required"/>
</extension>
</simpleContent>
</complexType>
</element>
You can also use the xmime:base64Binary type to express the above mentioned data much more cleanly.
<element name="MyBinaryData" xmime:expectedContentTypes='image/jpeg' type="xmime:base64Binary"/>
Let's define a full, validated doc/lit style WSDL that uses the xmime schema, has a service that receives a file and saves it in the server using the given path.
<wsdl:definitions xmlns:tns="http://ws.apache.org/axis2/mtomsample/" xmlns:mime="http://schemas.xmlsoap.org/wsdl/mime/" xmlns:http="http://schemas.xmlsoap.org/wsdl/http/" xmlns:soap12="http://schemas.xmlsoap.org/wsdl/soap12/" xmlns:xmime="http://www.w3.org/2005/05/xmlmime" xmlns:wsaw="http://www.w3.org/2006/05/addressing/wsdl" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns="http://schemas.xmlsoap.org/wsdl/" targetNamespace="http://ws.apache.org/axis2/mtomsample/"> <wsdl:types> <xsd:schema xmlns="http://schemas.xmlsoap.org/wsdl/" attributeFormDefault="qualified" elementFormDefault="qualified" targetNamespace="http://ws.apache.org/axis2/mtomsample/"> <xsd:import namespace="http://www.w3.org/2005/05/xmlmime" schemaLocation="http://www.w3.org/2005/05/xmlmime" /> <xsd:complexType name="AttachmentType"> <xsd:sequence> <xsd:element minOccurs="0" name="fileName" type="xsd:string" /> <xsd:element minOccurs="0" name="binaryData" type="xmime:base64Binary" /> </xsd:sequence> </xsd:complexType> <xsd:element name="AttachmentRequest" type="tns:AttachmentType" /> <xsd:element name="AttachmentResponse" type="xsd:string" /> </xsd:schema> </wsdl:types> <wsdl:message name="AttachmentRequest"> <wsdl:part name="part1" element="tns:AttachmentRequest" /> </wsdl:message> <wsdl:message name="AttachmentResponse"> <wsdl:part name="part1" element="tns:AttachmentResponse" /> </wsdl:message> <wsdl:portType name="MTOMServicePortType"> <wsdl:operation name="attachment"> <wsdl:input message="tns:AttachmentRequest" wsaw:Action="attachment" /> <wsdl:output message="tns:AttachmentResponse" wsaw:Action="http://schemas.xmlsoap.org/wsdl/MTOMServicePortType/AttachmentResponse" /> </wsdl:operation> </wsdl:portType> <wsdl:binding name="MTOMServiceSOAP11Binding" type="tns:MTOMServicePortType"> <soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="document" /> <wsdl:operation name="attachment"> <soap:operation soapAction="attachment" style="document" /> <wsdl:input> <soap:body use="literal" /> </wsdl:input> <wsdl:output> <soap:body use="literal" /> </wsdl:output> </wsdl:operation> </wsdl:binding> <wsdl:binding name="MTOMServiceSOAP12Binding" type="tns:MTOMServicePortType"> <soap12:binding transport="http://schemas.xmlsoap.org/soap/http" style="document" /> <wsdl:operation name="attachment"> <soap12:operation soapAction="attachment" style="document" /> <wsdl:input> <soap12:body use="literal" /> </wsdl:input> <wsdl:output> <soap12:body use="literal" /> </wsdl:output> </wsdl:operation> </wsdl:binding> <wsdl:service name="MTOMSample"> <wsdl:port name="MTOMSampleSOAP11port_http" binding="tns:MTOMServiceSOAP11Binding"> <soap:address location="http://localhost:8080/axis2/services/MTOMSample" /> </wsdl:port> <wsdl:port name="MTOMSampleSOAP12port_http" binding="tns:MTOMServiceSOAP12Binding"> <soap12:address location="http://localhost:8080/axis2/services/MTOMSample" /> </wsdl:port> </wsdl:service> </wsdl:definitions>
The important point here is we import http://www.w3.org/2005/05/xmlmime and define an element, 'binaryData' , that utilizes MTOM.
The next step is using the Axis2 tool 'WSDL2Java' to generate java source files from this WSDL. See the 'Code Generator Tool' guide for more info. Here, we define an ant task that chooses ADB (Axis2 Data Binding) as the databinding implementation. The name we list for the WSDL above is MTOMSample.wsdl, and we define our package name for our generated source files to be 'sample.mtom.service' . Our ant task for this example is:
<target name="generate.service">
<java classname="org.apache.axis2.wsdl.WSDL2Java">
<arg value="-uri" />
<arg value="${basedir}/resources/MTOMSample.wsdl" />
<arg value="-ss" />
<arg value="-sd" />
<arg value="-g"/>
<arg value="-p" />
<arg value="sample.mtom.service" />
<arg value="-o" />
<arg value="${service.dir}" />
<classpath refid="class.path" />
</java>
</target>
Now we are ready to code. Lets edit output/src/sample/mtom/service/MTOMSampleSkeleton.java and fill in the business logic. Following is an example:
public org.apache.ws.axis2.mtomsample.AttachmentResponse attachment(
org.apache.ws.axis2.mtomsample.AttachmentRequest param0) throws Exception
{
AttachmentType attachmentRequest = param0.getAttachmentRequest();
Base64Binary binaryData = attachmentRequest.getBinaryData();
DataHandler dataHandler = binaryData.getBase64Binary();
File file = new File(
attachmentRequest.getFileName());
FileOutputStream fileOutputStream = new FileOutputStream(file);
dataHandler.writeTo(fileOutputStream);
fileOutputStream.flush();
fileOutputStream.close();
AttachmentResponse response = new AttachmentResponse();
response.setAttachmentResponse("File saved succesfully.");
return response;
}
The code above receives a file and writes it to disk using the given file name. It returns a message on success. Now lets define the client:
public static void transferFile(File file, String destination)
throws RemoteException {
MTOMSampleStub serviceStub = new MTOMSampleStub();
// Enable MTOM in the client side
serviceStub._getServiceClient().getOptions().setProperty(
Constants.Configuration.ENABLE_MTOM, Constants.VALUE_TRUE);
//Increase the time out when sending large attachments
serviceStub._getServiceClient().getOptions().setTimeOutInMilliSeconds(10000);
// Populating the code generated beans
AttachmentRequest attachmentRequest = new AttachmentRequest();
AttachmentType attachmentType = new AttachmentType();
Base64Binary base64Binary = new Base64Binary();
// Creating a javax.activation.FileDataSource from the input file.
FileDataSource fileDataSource = new FileDataSource(file);
// Create a dataHandler using the fileDataSource. Any implementation of
// javax.activation.DataSource interface can fit here.
DataHandler dataHandler = new DataHandler(fileDataSource);
base64Binary.setBase64Binary(dataHandler);
base64Binary.setContentType(dataHandler.getContentType());
attachmentType.setBinaryData(base64Binary);
attachmentType.setFileName(destination);
attachmentRequest.setAttachmentRequest(attachmentType);
AttachmentResponse response = serviceStub.attachment(attachmentRequest);
System.out.println(response.getAttachmentResponse());
}
The last step is to create an AAR with our Skeleton and the services.xml, and then deploy the service. You can find the completed sample in the Axis2 standard binary distribution under the samples/mtom directory
Lets define a full, validated doc / lit style WSDL that imports the xmime schema, has a service that receives a jpeg and returns a pass / fail status to the client:
<?xml version="1.0" encoding="UTF-8"?>
<definitions name="MyMTOMService" targetNamespace="http://myMtomNS" xmlns:tns="http://myMtomNS" xmlns="http://schemas.xmlsoap.org/wsdl/"
xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:ns2="http://myMtomNS/types">
<types>
<schema targetNamespace="http://myMtomNS/types" elementFormDefault="qualified" xmlns:tns="http://myMtomNS/types"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns="http://www.w3.org/2001/XMLSchema"
xmlns:xmime="http://www.w3.org/2005/05/xmlmime">
<import namespace="http://schemas.xmlsoap.org/soap/encoding/"/>
<import namespace="http://www.w3.org/2005/05/xmlmime"
schemaLocation="http://www.w3.org/2005/05/xmlmime"/>
<complexType name="ReturnWebBase">
<sequence>
<element name="errorMessage" type="xsd:string"/>
<element name="successErrorCode" type="xsd:int"/>
</sequence>
</complexType>
<element name="MyBinaryData" xmime:expectedContentTypes='image/jpeg' >
<complexType>
<simpleContent>
<extension base="base64Binary" >
<attribute ref="xmime:contentType" use="required"/>
</extension>
</simpleContent>
</complexType>
</element>
<element name="sendData">
<complexType>
<sequence>
<element ref='tns:MyBinaryData' minOccurs="1" maxOccurs="1" />
</sequence>
</complexType>
</element>
<element name="sendDataResponse">
<complexType>
<sequence>
<element minOccurs="1" maxOccurs="1" name="sendDataResult" type="tns:ReturnWebBase" />
</sequence>
</complexType>
</element>
</schema>
</types>
<message name="MyMTOMEndpoint_sendData">
<part name="parameters" element="ns2:sendData"/>
</message>
<message name="MyMTOMEndpoint_sendDataResponse">
<part name="result" element="ns2:sendDataResponse"/>
</message>
<portType name="MyMTOMEndpoint">
<operation name="sendData">
<input message="tns:MyMTOMEndpoint_sendData" name="MyMTOMEndpoint_sendData"/>
<output message="tns:MyMTOMEndpoint_sendDataResponse" name="MyMTOMEndpoint_sendDataResponse"/>
</operation>
</portType>
<binding name="MyMTOMEndpointBinding" type="tns:MyMTOMEndpoint">
<soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="document"/>
<operation name="sendData">
<soap:operation soapAction="sendData"/>
<input name="MyMTOMEndpoint_sendData">
<soap:body use="literal"/>
</input>
<output name="MyMTOMEndpoint_sendDataResponse">
<soap:body use="literal"/>
</output>
</operation>
</binding>
<service name="MyMTOMService">
<port name="MyMTOMEndpointPort" binding="tns:MyMTOMEndpointBinding">
<soap:address location="http://localhost:8080/axis2/services/MyMTOMService"/></port></service></definitions>
The important point here is we import http://www.w3.org/2005/05/xmlmime and define an element, 'MyBinaryData' , that utilizes MTOM.
The next step is using the Axis2 tool 'WSDL2Java' to generate java source files from this WSDL. See the 'Code Generator Tool' guide for more info. Here, we define an ant task that chooses XMLBeans as the databinding implementation. We also choose to generate an interface which our Skeleton will implement. The name we list for the WSDL above is mtomExample.wsdl, and we define our package name for our generated source files to be 'org.apache.axis2.samples.mtomDatabinding.endpoint' . Our ant task for this example is:
<target name="wsdl2java" depends="clean,prepare">
<delete dir="output" />
<java classname="org.apache.axis2.wsdl.WSDL2Java" fork="true">
<classpath refid="axis.classpath"/>
<arg value="-d"/>
<arg value="xmlbeans"/>
<arg value="-uri"/>
<arg file="wsdl/mtomExample.wsdl"/>
<arg value="-ss"/>
<arg value="-ssi"/>
<arg value="-g"/>
<arg value="-sd"/>
<arg value="-o"/>
<arg file="output"/>
<arg value="-p"/>
<arg value="org.apache.axis2.samples.mtomDatabinding.endpoint"/>
</java>
<!-- Move the schema folder to classpath-->
<move todir="${build.classes}">
<fileset dir="output/resources">
<include name="*schema*/**/*.class"/>
<include name="*schema*/**/*.xsb"/>
</fileset>
</move>
</target>
Now we are ready to code. Lets edit output/src/org/apache/axis2/samples/mtomDatabinding/endpoint/MyMTOMServiceSkeleton.java and fill in the business logic. The end result becomes:
/**
* MyMTOMServiceSkeleton.java
*
* This file was auto-generated from WSDL
* by the Apache Axis2 version: SNAPSHOT Jul 19, 2006 (03:46:19 BRT)
*/
package org.apache.axis2.samples.mtomDatabinding.endpoint;
import java.io.File;
import java.io.FileOutputStream;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import mymtomns.types.ReturnWebBase;
import mymtomns.types.SendDataDocument;
import mymtomns.types.SendDataResponseDocument;
import mymtomns.types.MyBinaryDataDocument.MyBinaryData;
import mymtomns.types.SendDataDocument.SendData;
import mymtomns.types.SendDataResponseDocument.SendDataResponse;
/**
* MyMTOMServiceSkeleton java skeleton for the axisService
*/
public class MyMTOMServiceSkeleton implements MyMTOMServiceSkeletonInterface {
/** commons logging declaration. * */
private static Log logger = LogFactory
.getLog(MyMTOMServiceSkeleton.class);
/** Put file received here - change path for your system. */
private static final String MY_DIR = "/home/myuser/example_dir/output";
/** Success code. */
public static final Integer SUCCESS = new Integer(0);
/** Failure / Exception code. */
public static final Integer FAILURE = new Integer(-1);
/**
* Auto generated method signature.
*
* @param sendDataDocument
* input complex object
* @return SendDataResponseDocument complex object return values
*/
public SendDataResponseDocument sendData (SendDataDocument sendDataDocument) {
// prepare output
SendDataResponseDocument retDoc = SendDataResponseDocument.Factory
.newInstance();
SendDataResponse retElement = SendDataResponse.Factory
.newInstance();
ReturnWebBase returnWebBase = ReturnWebBase.Factory
.newInstance();
try {
if (logger.isDebugEnabled()) {
logger.debug("Reached mtomExample on the server side...");
}
SendData sendData = sendDataDocument.getSendData();
MyBinaryData myBinaryData = sendData.getMyBinaryData();
byte [] myJpegBytes = myBinaryData.getByteArrayValue();
File jpegFile = new File(MY_DIR+"myJpeg.jpg");
FileOutputStream fos = new FileOutputStream(jpegFile);
fos.write( myJpegBytes );
fos.flush();
fos.close();
returnWebBase.setSuccessErrorCode(SUCCESS);
returnWebBase.setErrorMessage("SUCCESS");
} catch (Exception ex) {
logger.error("MyMTOMServiceSkeleton.sendData error:"
+ ex.getMessage(), ex);
returnWebBase.setErrorMessage(ex.getMessage());
returnWebBase.setSuccessErrorCode(FAILURE);
}
retElement.setSendDataResult(returnWebBase);
retDoc.setSendDataResponse(retElement);
return retDoc;
}
}
The code above receives a jpeg file and writes it to disk. It returns zero on success and in the case of an error, returns -1 along with a stacktrace. Now lets define the client:
package client;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileInputStream;
import mymtomns.types.ReturnWebBase;
import mymtomns.types.SendDataDocument;
import mymtomns.types.SendDataResponseDocument;
import mymtomns.types.MyBinaryDataDocument.MyBinaryData;
import mymtomns.types.SendDataDocument.SendData;
import mymtomns.types.SendDataResponseDocument.SendDataResponse;
import org.apache.axis2.samples.mtomDatabinding.endpoint.MyMTOMServiceStub;
public class MTOMXMLBeansClient {
/** Read file from here - change path for your system. */
private static final String MY_DIR = "/home/myuser/example_dir/input/";
public static void main(String [] args) throws Exception {
try {
SendData sendData
= SendData.Factory
.newInstance();
SendDataDocument doc
= SendDataDocument.Factory
.newInstance();
MyBinaryData myBinaryData
= MyBinaryData.Factory
.newInstance();
File file=new File(MY_DIR + "axis.jpg");
FileInputStream stream=new FileInputStream(file);
int size=stream.available();
byte[] bytes=new byte[size];
stream.read(bytes);
myBinaryData.setByteArrayValue(bytes);
sendData.setMyBinaryData(myBinaryData);
doc.setSendData(sendData);
MyMTOMServiceStub stub = new MyMTOMServiceStub();
SendDataResponseDocument responseDoc = stub
.sendData(doc);
SendDataResponse response = responseDoc
.getSendDataResponse();
ReturnWebBase result = response.getSendDataResult();
// test for errors
if (result.getSuccessErrorCode() ==-1) {
System.out.println("ERROR: " + result.getErrorMessage());
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
The last step is to create an AAR with our Skeleton and the generated interface and services.xml, and then deploy the service. See the user guide for more info.
Axis2 automatically identifies SwA messages based on the content type. Axis2 stores the references to the received attachment parts (MIME parts) in the Message Context. Axis2 preserves the order of the received attachments when storing them in the MessageContext. Users can access binary attachments using the attachement API given in the Message Context using content-id of the mime part as the key. Care needs be taken to rip off the "cid" prefix when content-id is taken from the "Href" attributes. Users can access the the message context from whithin a service implementation class using the "setOperationContext()" method as shown in the following example.
Note: Axis2 supports content-id based referencing only. Axis2 does not support Content Location based referencing of MIME parts.
public class SwA {
private OperationContext operationContext;
public SwA() {
}
public void setOperationContext(OperationContext oc) throws AxisFault {
operationContext = oc;
}
public void uploadAttachment(OMElement omEle) throws AxisFault {
OMElement child = (OMElement) omEle.getFirstOMChild();
OMAttribute attr = child.getAttribute(new QName("href"));
//Content ID processing
String contentID = attr.getAttributeValue();
contentID = contentID.trim();
if (contentID.substring(0, 3).equalsIgnoreCase("cid")) {
contentID = contentID.substring(4);
}
Attachments attachment = (Attachments) (operationContext.getMessageContext(WSDLConstants.MESSAGE_LABEL_IN_VALUE)).getAttachmentMap();
DataHandler dataHandler = attachment.getDataHandler(contentID);
...........
}
}
User need to set the "enableSwA" property to true in order to be able to send SwA messages. Axis2 user is not expected to enable MTOM & SwA together. In such a situation MTOM will get priority over SwA.
This can be set using the axis2.xml as follows.
<parameter name="enableSwA" locked="false">true</parameter>
"enableSwA" can also be set using the client side Options as follows
options.setProperty(Constants.Configuration.ENABLE_SwA, Constants.VALUE_TRUE);
Users are expected to use the attachment API provided in the MessageContext to specify the binary attachments needed to be attached to the outgoing message as SwA type attachments. Client side SwA capability can be used only with the OperationClient api, since the user needs the ability to access the MessageContext.
public void uploadFileUsingSwA(String fileName) throws Exception {
Options options = new Options();
options.setTo(targetEPR);
options.setProperty(Constants.Configuration.ENABLE_SWA, Constants.VALUE_TRUE);
options.setTransportInProtocol(Constants.TRANSPORT_HTTP);
options.setSoapVersionURI(SOAP11Constants.SOAP_ENVELOPE_NAMESPACE_URI);
options.setTo(targetEPR);
ServiceClient sender = new ServiceClient(null,null);
sender.setOptions(options);
OperationClient mepClient = sender.createClient(ServiceClient.ANON_OUT_IN_OP);
MessageContext mc = new MessageContext();
mc.setEnvelope(createEnvelope());
FileDataSource fileDataSource = new FileDataSource("test-resources/mtom/test.jpg");
DataHandler dataHandler = new DataHandler(fileDataSource);
mc.addAttachment("FirstAttachment",dataHandler);
mepClient.addMessageContext(mc);
mepClient.execute(true);
}
MTOM specification is designed to be backward compatible with the SOAP with Attachments specification. Even though the representation is different, both technologies have the same wire format. We can safely assume that any SOAP with Attachments endpoint can accept a MTOM optimized messages and treat them as SOAP with Attachment messages - Any MTOM optimized message is a valid SwA message.
Note : Above backword compatibility was succesfully tested against Axis 1.x
Content-Type: multipart/related; type="text/xml";
start="<9D645C8EBB837CE54ABD027A3659535D>";
boundary="----=_Part_0_1977511.1123163571138"
------=_Part_0_1977511.1123163571138
Content-Type: text/xml; charset=UTF-8
Content-Transfer-Encoding: binary
Content-Id: <9D645C8EBB837CE54ABD027A3659535D>
<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv="...."....>
........
<source href="cid:3936AE19FBED55AE4620B81C73BDD76E" xmlns="/>
........
</soapenv:Envelope>
------=_Part_0_1977511.1123163571138
Content-Type: text/plain
Content-Transfer-Encoding: binary
Content-Id: <3936AE19FBED55AE4620B81C73BDD76E>
Binary Data.....
------=_Part_0_1977511.1123163571138--
Content-Type: multipart/related; boundary=MIMEBoundary4A7AE55984E7438034;
type="application/xop+xml"; start="<0.09BC7F4BE2E4D3EF1B@apache.org>";
start-info="text/xml; charset=utf-8"
--MIMEBoundary4A7AE55984E7438034
content-type: application/xop+xml; charset=utf-8; type="application/soap+xml;"
content-transfer-encoding: binary
content-id: <0.09BC7F4BE2E4D3EF1B@apache.org>
<?xml version='1.0' encoding='utf-8'?>
<soapenv:Envelope xmlns:soapenv="...."....>
........
<xop:Include href="cid:1.A91D6D2E3D7AC4D580@apache.org"
xmlns:xop="http://www.w3.org/2004/08/xop/include">
</xop:Include>
........
</soapenv:Envelope>
--MIMEBoundary4A7AE55984E7438034
content-type: application/octet-stream
content-transfer-encoding: binary
content-id: <1.A91D6D2E3D7AC4D580@apache.org>
Binary Data.....
--MIMEBoundary4A7AE55984E7438034--
Axis2 comes handy with a file caching mechanism for incoming attachments, which gives Axis2 the ability to handle very large attachments without buffering them in memory at any time. Axis2 file caching streams the incoming MIME parts directly in to files, after reading the MIME part headers.
Also a user can specify a size threshold for the File caching (in bytes). When this threshold value is specified, only the attachments whose size is bigger than the threshold value will get cached in files. Smaller attachments will remain in Memory.
NOTE : It is a must to specify a directory to temporary store the attachments. Also care should be taken to clean that directory from time to time.
The following parameters need to be set in Axis2.xml in order to enable file caching.
<axisconfig name="AxisJava2.0">
<!-- ================================================= -->
<!-- Parameters -->
<!-- ================================================= -->
<parameter name="cacheAttachments" locked="false">true</parameter>
<parameter name="attachmentDIR" locked="false">temp directory</parameter>
<parameter name="sizeThreshold" locked="false">4000</parameter>
.........
.........
</axisconfig>
Enabling file caching for client side receiving can be done for the by setting the Options as follows.
options.setProperty(Constants.Configuration.CACHE_ATTACHMENTS,Constants.VALUE_TRUE); options.setProperty(Constants.Configuration.ATTACHMENT_TEMP_DIR,TempDir); options.setProperty(Constants.Configuration.FILE_SIZE_THRESHOLD, "4000");