(DataFlex) How to Access Parts of a multipart/related HTTP Response

Demonstrates how to access the parts of a multipart/related response. This example sends a ficticious multipart/related request, and handles a ficticious multipart/related response.

We send the following multipart/related request:

Content-Type: multipart/related; start-info="text/xml"; type="application/xop+xml"; boundary="----=_Part_0_1744155.1118953559416"
Content-Length: 3453
SOAPAction: "some-SOAP-action"

------=_Part_1_4558657.1118953559446
Content-Type: application/xop+xml; type="text/xml"; charset=utf-8

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
    <Detail xmlns="http://example.org/mtom/data">
      <image>
        <xop:Include xmlns:xop="http://www.w3.org/2004/08/xop/include" href="cid:5aeaa450-17f0-4484-b845-a8480c363444@example.org" />
      </image>
    </Detail>
  </soap:Body>
</soap:Envelope>

------=_Part_1_4558657.1118953559446
Content-Type: image/jpeg
Content-ID: <5aeaa450-17f0-4484-b845-a8480c363444@example.org>


... binary data ...

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    Handle hoHttp
    Handle hoSoapXml
    Boolean iSuccess
    String sXmlBody
    Variant vReq
    Handle hoReq
    Boolean iUseTls
    Variant vResp
    Handle hoResp
    Handle hoMime
    Variant vPart0
    Handle hoPart0
    String sSubPartXmlBody
    String sTemp1
    Integer iTemp1
    Boolean bTemp1

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    Get Create (RefClass(cComChilkatHttp)) To hoHttp
    If (Not(IsComObjectCreated(hoHttp))) Begin
        Send CreateComObject of hoHttp
    End

    Get Create (RefClass(cComChilkatXml)) To hoSoapXml
    If (Not(IsComObjectCreated(hoSoapXml))) Begin
        Send CreateComObject of hoSoapXml
    End

    // Build the following SOAP XML

    // <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
    //   <soap:Body>
    //     <Detail xmlns="http://example.org/mtom/data">
    //       <image>
    //         <xop:Include xmlns:xop="http://www.w3.org/2004/08/xop/include" href="cid:5aeaa450-17f0-4484-b845-a8480c363444@example.org" />
    //       </image>
    //     </Detail>
    //   </soap:Body>
    // </soap:Envelope>

    Set ComTag Of hoSoapXml To "soap:Envelope"
    Get ComAddAttribute Of hoSoapXml "xmlns:soap" "http://schemas.xmlsoap.org/soap/envelope/" To iSuccess
    Get ComUpdateAttrAt Of hoSoapXml "soap:Body|Detail" True "xmlns" "http://example.org/mtom/data" To iSuccess
    Get ComUpdateAttrAt Of hoSoapXml "soap:Body|Detail|image|xop:Include" True "xmlns:xop" "http://www.w3.org/2004/08/xop/include" To iSuccess
    Get ComUpdateAttrAt Of hoSoapXml "soap:Body|Detail|image|xop:Include" True "href" "cid:5aeaa450-17f0-4484-b845-a8480c363444@example.org" To iSuccess

    Set ComEmitXmlDecl Of hoSoapXml To False
    Get ComGetXml Of hoSoapXml To sXmlBody
    Showln sXmlBody

    Get Create (RefClass(cComChilkatHttpRequest)) To hoReq
    If (Not(IsComObjectCreated(hoReq))) Begin
        Send CreateComObject of hoReq
    End
    Set ComHttpVerb Of hoReq To "POST"
    Set ComPath Of hoReq To "/something/someTarget"

    Set ComContentType Of hoReq To 'multipart/related; start-info="text/xml"; type="application/xop+xml"'
    Send ComAddHeader To hoReq "SOAPAction" "some-SOAP-action"

    Get ComAddStringForUpload2 Of hoReq "" "" sXmlBody "utf-8" 'application/xop+xml; type="text/xml"; charset=utf-8' To iSuccess

    // The bytes will be sent as binary (not base64 encoded).
    Get ComAddFileForUpload2 Of hoReq "" "qa_data/jpg/starfish.jpg" "image/jpeg" To iSuccess

    // The JPEG data is the 2nd sub-part, and therefore is at index 1 (the first sub-part is at index 0)
    Get ComAddSubHeader Of hoReq 1 "Content-ID" "<5aeaa450-17f0-4484-b845-a8480c363444@example.org>" To iSuccess

    Set ComFollowRedirects Of hoHttp To True

    Move True To iUseTls
    Get pvComObject of hoReq to vReq
    Get ComSynchronousRequest Of hoHttp "www.example.org" 443 iUseTls vReq To vResp
    If (IsComObject(vResp)) Begin
        Get Create (RefClass(cComChilkatHttpResponse)) To hoResp
        Set pvComObject Of hoResp To vResp
    End
    Get ComLastMethodSuccess Of hoHttp To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoHttp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Imagine the HTTP response is multipart related and is something like this:

    // HTTP/1.1 200 OK
    // Cache-Control: no-cache, no-store
    // Pragma: no-cache
    // Transfer-Encoding: chunked
    // Content-Type: multipart/related; boundary=------------080001080500020607080905
    // Expires: -1
    // Server: Microsoft-IIS/10.0
    // X-AspNet-Version: 4.0.30319
    // X-Powered-By: ASP.NET
    // Date: Wed, 19 Feb 2020 15:27:06 GMT
    // 
    // --------------080001080500020607080905
    // Content-Type: application/xop+xml; charset=iso-8859-1
    // Content-Id: RootPart
    // Content-Transfer-Encoding: binary
    // 
    // <?xml version="1.0" encoding="iso-8859-1"?>
    // <soapenv:Envelope xmlns:xcpt="...">
    //   <soapenv:Header />
    //   <soapenv:Body>
    //     <xres:Transport profile="http://something.example.com/..." version="1.4">
    //       <xres:TransportHeader>
    // 	...
    // 	...
    //       </xres:TransportHeader>
    //       <xres:TransportBody />
    //     </xres:Transport>
    //   </soapenv:Body>
    // </soapenv:Envelope>
    // --------------080001080500020607080905--

    // To get the XML, load the full MIME of the response into a Chilkat MIME object.  Then get the body of the 1st sub-part.
    Get Create (RefClass(cComChilkatMime)) To hoMime
    If (Not(IsComObjectCreated(hoMime))) Begin
        Send CreateComObject of hoMime
    End
    Get ComFullMime Of hoResp To sTemp1
    Get ComLoadMime Of hoMime sTemp1 To iSuccess

    // Your code might verify that the Content-Type is indeed multipart/related.
    Get ComContentType Of hoMime To sTemp1
    Showln sTemp1
    Get ComNumParts Of hoMime To iTemp1
    Showln "num parts = " iTemp1

    // Assuming it is, and the number of sub-parts is > 0
    Get ComNumParts Of hoMime To iTemp1
    If (iTemp1 > 0) Begin
        Get ComGetPart Of hoMime 0 To vPart0
        If (IsComObject(vPart0)) Begin
            Get Create (RefClass(cComChilkatMime)) To hoPart0
            Set pvComObject Of hoPart0 To vPart0
        End
        // The Content-Type (in this ficticious example) should be "application/xop+xml"
        Get ComContentType Of hoPart0 To sTemp1
        Showln "sub-part Content-Type: " sTemp1
        // Now get the XML 
        Get ComGetBodyDecoded Of hoPart0 To sSubPartXmlBody
        Showln sSubPartXmlBody
        Send Destroy of hoPart0
    End

    Send Destroy of hoResp


End_Procedure