将二进制文件提取为 base64 字符串会导致文件不完整？

Question

I am trying to extract binary from soap response and convert it to base64 string but what happens is that I get part of the binary converted to base64 not the full binary data.

Integration Studio: 8.1.0

the soap response is as following:

--A-B--MIME-BOUNDARY--27d99311536fa8c4-18606176189--Y-Z
Content-Transfer-Encoding: binary
Content-Type: application/xop+xml; type="application/soap+xml"; charset=UTF-8
Content-ID: 
<v0-27d99311536fa8c4-18606176189@mtom.p8ce.filenet.com>
    <?xml version="1.0" encoding="UTF-8"?>
    <e:Envelope xmlns:d="http://www.w3.org/2001/XMLSchema" xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns:fn35="http://www.filenet.com/ns/fnce/2005/02/ws/schema" xmlns:fn40m="http://www.filenet.com/ns/fnce/2006/11/ws/MTOM/schema" xmlns:fn40="http://www.filenet.com/ns/fnce/2006/11/ws/schema" xmlns:xop="http://www.w3.org/2004/08/xop/include" xmlns:e="http://schemas.xmlsoap.org/soap/envelope/">
        <e:Body>
            <GetContentResponse xmlns="http://www.filenet.com/ns/fnce/2006/11/ws/schema">
                <ContentResponse id="1" i:type="fn40:ContentElementResponse" retrievalName="test.pdf" totalSize="4586622" bufferedSize="1048576" continueFrom="offset=1048576;id={B3795692-DA06-468C-AEC9-523A3715455D};">
                    <SourceSpecification i:type="fn40:ObjectReference" classId="Document" objectId="{E408981D-FF67-4D91-B7A9-CEBEC4630AB0}" objectStore="MCIDEV"></SourceSpecification>
                    <ElementSpecification elementSequenceNumber="0"></ElementSpecification>
                    <Content i:type="fn40:InlineContent">
                        <Binary>
                            <xop:Include href="cid:v1-27d99311536fa8c4-18606176189@mtom.p8ce.filenet.com"></xop:Include>
                        </Binary>
                    </Content>
                </ContentResponse>
            </GetContentResponse>
        </e:Body>
    </e:Envelope>
--A-B--MIME-BOUNDARY--27d99311536fa8c4-18606176189--Y-Z
Content-Transfer-Encoding: binary
Content-Type: application/octet-stream
Content-Id: 
    <v1-27d99311536fa8c4-18606176189@mtom.p8ce.filenet.com>

%PDF-1.4
......
......
......
--A-B--MIME-BOUNDARY--27d99311536fa8c4-18606176189--Y-Z--

The code to extract the binary and convert it to base64 string is as follows:

<property expression="$body/fn:GetContentResponse/fn:ContentResponse/fn:Content/fn:Binary" name="DataBase64" scope="default" type="STRING" xmlns:fn="http://www.filenet.com/ns/fnce/2006/11/ws/schema"/>

My service code is as follows:

<?xml version="1.0" encoding="UTF-8"?>
<sequence name="StorageGetDocumentSeq" trace="disable" xmlns="http://ws.apache.org/ns/synapse">
    <propertyGroup>
        <property expression="json-eval($.username)" name="Username" scope="default" type="STRING"/>
        <property expression="json-eval($.password)" name="Password" scope="default" type="STRING"/>
        <property expression="json-eval($.objectStore)" name="ObjectStore" scope="default" type="STRING"/>
        <property name="DocumentClass" scope="default" type="STRING" value="Document"/>
        <property expression="json-eval($.documentId)" name="DocumentId" scope="default" type="STRING"/>
        <property expression="json-eval($.version)" name="Version" scope="default" type="STRING"/>
    </propertyGroup>
    <sequence key="StorageRequestValidatorSeq"/>
    <script description="Response Builder" language="js"><![CDATA[var errors = [];
    var errorProperties = mc.getPropertyKeySet();
    var it = errorProperties.iterator();      
            var i = 1;
            while(it.hasNext()){              
               var prop = it.next();
               if (prop.contains('Error')) {              
                print(prop.toString());
                errors.push(mc.getProperty(prop));     
               }    
            }
    mc.setProperty('errorList', "[" + errors.toString() + "]");]]></script>
    <filter regex="false" source="get-property('IsValid')">
        <then>
            <payloadFactory description="Response Payload" media-type="json">
                <format>
                    {"errorCode":400,"errorMessage":"One or more validation error","errorList":$1}</format>
                <args>
                    <arg evaluator="xml" expression="get-property('errorList')"/>
                </args>
            </payloadFactory>
            <property description="Set 400 response code" name="HTTP_SC" scope="axis2" type="STRING" value="400"/>
            <respond description="Response to client"/>
        </then>
        <else/>
    </filter>
    <sequence key="StorageGetMimeTypeSeq"/>
    <payloadFactory media-type="xml">
        <format>
            <soapenv:Envelope xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                <soapenv:Header>
                    <Security xmlns="http://schemas.xmlsoap.org/ws/2002/12/secext">
                        <hd:UsernameToken xmlns:hd="http://schemas.xmlsoap.org/ws/2002/12/secext">
                            <hd:Username>$1</hd:Username>
                            <hd:Password>$2</hd:Password>
                        </hd:UsernameToken>
                    </Security>
                </soapenv:Header>
                <soapenv:Body>
                    <p857:GetContentRequest validateOnly="0" xmlns:p857="http://www.filenet.com/ns/fnce/2006/11/ws/schema">
                        <p857:ContentRequest continueFrom="" cacheAllowed="1" id="1" startOffset="0">
                            <p857:SourceSpecification classId="$4" itemIndex="0" objectId="$5" objectStore="$3" 
                            serializationDuplicate="0" xsi:type="p857:ObjectSpecification"/>
                            <p857:ElementSpecification elementSequenceNumber="0" itemIndex="0"/>
                        </p857:ContentRequest>
                    </p857:GetContentRequest>
                </soapenv:Body>
            </soapenv:Envelope>
        </format>
        <args>
            <arg evaluator="xml" expression="get-property('Username')"/>
            <arg evaluator="xml" expression="get-property('Password')"/>
            <arg evaluator="xml" expression="get-property('ObjectStore')"/>
            <arg evaluator="xml" expression="get-property('DocumentClass')"/>
            <arg evaluator="xml" expression="get-property('DocumentId')"/>
        </args>
    </payloadFactory>
    <call-template target="StorageEndpointTemplate"/>
    <propertyGroup>
        <property expression="$axis2:HTTP_SC" name="HTTPStatus" scope="default" type="STRING"/>
        <property expression="$body/e:Fault/e:Reason/e:Text" name="ErrorMessage" scope="default" type="STRING" xmlns:e="http://www.w3.org/2003/05/soap-envelope"/>
        <property expression="$body/fn:GetContentResponse/fn:ContentResponse/@retrievalName" name="FileName" scope="default" type="STRING" xmlns:fn="http://www.filenet.com/ns/fnce/2006/11/ws/schema"/>
        <property expression="$body/fn:GetContentResponse/fn:ContentResponse/@totalSize" name="FileSize" scope="default" type="STRING" xmlns:fn="http://www.filenet.com/ns/fnce/2006/11/ws/schema"/>
        <property expression="$body/fn:GetContentResponse/fn:ContentResponse/fn:Content/fn:Binary" name="DataBase64" scope="default" type="STRING" xmlns:fn="http://www.filenet.com/ns/fnce/2006/11/ws/schema"/>
    </propertyGroup>
    <log level="headers"/>
    <log level="custom">
        <property expression="get-property('FileName')" name="FileNameLog"/>
        <property expression="get-property('FileSize')" name="FileSizeLog"/>
    </log>
    <filter regex="true" source="boolean(get-property('ErrorMessage'))=''">
        <then>
            <payloadFactory media-type="json">
                <format>
                {
                 "fileName":"$1",
                 "fileSize": $2,
                 "mimeType":"$3",
                 "dataBase64":"$4"
                }
                </format>
                <args>
                    <arg evaluator="xml" expression="get-property('FileName')"/>
                    <arg evaluator="xml" expression="get-property('FileSize')"/>
                    <arg evaluator="xml" expression="get-property('MimeType')"/>
                    <arg evaluator="xml" expression="get-property('DataBase64')"/>
                </args>
            </payloadFactory>
        </then>
        <else>
            <property name="HTTP_SC" scope="axis2" type="STRING" value="400"/>
            <payloadFactory description="Response Payload" media-type="json">
                <format>{"errorCode": "$1","errorMessage": "$2"}</format>
                <args>
                    <arg value="400"/>
                    <arg evaluator="xml" expression="get-property('ErrorMessage')"/>
                </args>
            </payloadFactory>
        </else>
    </filter>
</sequence>

EDIT : I also tried the base64Encode as follows:

<property expression="base64Encode($body/fn:GetContentResponse/fn:ContentResponse/fn:Content/fn:Binary)" name="DataBase64" scope="default" type="STRING" xmlns:fn="http://www.filenet.com/ns/fnce/2006/11/ws/schema"/>

And it also results in corrupted base64String

Answer 1

I found out that the issue was not related to WSO2 at all but a fil.net limitation

Inline Content Retrieval Limit default is 1 MB so that fil.net API itself was returning 1 MB only of the file.

https://www.ibm.com/docs/en/fil.net-p8-platform/5.5.x?topic=engine-improving-content-uploads-downloads