(MFC) eBay -- Download Data using FileTransferService

Demonstrates how to download a data file using the eBay File Transfer API.

Note: This example requires Chilkat v9.5.0.67 or later.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkHttp.h>
#include <CkHttpRequest.h>
#include <CkXml.h>
#include <CkHttpResponse.h>
#include <CkBinData.h>
#include <CkMime.h>
#include <CkStringBuilder.h>
#include <CkGzip.h>
#include <CkZip.h>
#include <CkZipEntry.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    // Use a previously obtained access token.  The token should look something like this:
    // "AgAAAA**AQA ..."
    const char *accessToken = "EBAY_ACCESS_TOKEN";

    CkHttp http;

    CkHttpRequest req;

    req.put_HttpVerb("POST");
    req.put_Path("/FileTransferService");
    req.put_ContentType("application/xml");

    // Build the XML body for the request.
    CkXml xml;
    xml.put_Tag("downloadFileRequest");
    xml.AddAttribute("xmlns","http://www.ebay.com/marketplace/services");
    xml.UpdateChildContent("taskReferenceId","50013004806");
    xml.UpdateChildContent("fileReferenceId","50015579016");

    req.LoadBodyFromString(xml.getXml(),"utf-8");

    // The XML body looks like this:

    // 	<?xml version="1.0" encoding="UTF-8"?>
    // 	<downloadFileRequest xmlns="http://www.ebay.com/marketplace/services">
    // 	<taskReferenceId>50013004806</taskReferenceId>
    // 	<fileReferenceId>50015579016</fileReferenceId>
    // 	</downloadFileRequest>

    req.AddHeader("X-EBAY-SOA-OPERATION-NAME","downloadFile");
    req.AddHeader("X-EBAY-SOA-SECURITY-TOKEN",accessToken);

    CkHttpResponse *resp = http.SynchronousRequest("storage.sandbox.ebay.com",443,true,req);
    if (http.get_LastMethodSuccess() != true) {
        strOut.append(http.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    int statusCode = resp->get_StatusCode();
    strOut.append("Response status code = ");
    strOut.appendInt(statusCode);
    strOut.append("\r\n");

    CkBinData responseBody;
    resp->GetBodyBd(responseBody);
    delete resp;

    // We can save the response body to a file for examination if we get an unanticipated response.  
    // (It's binary, so it won't open well in a text editor.)
    responseBody.WriteFile("qa_output/response.mime");

    if (statusCode != 200) {
        strOut.append("Failed.");
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // The response body looks like this:

    // 	--MIMEBoundaryurn_uuid_2B668636C1E17A4D4114925305818684241
    // 	Content-Type: application/xop+xml; charset=utf-8; type="text/xml"
    // 	Content-Transfer-Encoding: binary
    // 	Content-ID: <0.urn:uuid:2B668636C1E17A4D4114925305818684242>
    // 
    // 	<?xml version='1.0' encoding='UTF-8'?>
    // 	<downloadFileResponse xmlns="http://www.ebay.com/marketplace/services">
    // 	<ack>Success</ack>
    // 	<version>1.1.0</version>
    // 	<timestamp>2017-04-18T15:49:41.868Z</timestamp>
    // 	<fileAttachment>
    // 	    <Size>587</Size>
    // 	    <Data>
    //                 <xop:Include xmlns:xop="http://www.w3.org/2004/08/xop/include" href="cid:urn:uuid:A37C3C73E994C267F11492530585522"/>
    // 	    </Data>
    // 	</fileAttachment>
    // 	</downloadFileResponse>
    // 	--MIMEBoundaryurn_uuid_2B668636C1E17A4D4114925305818684241
    // 	Content-Type: application/zip
    // 	Content-Transfer-Encoding: binary
    // 	Content-ID: <urn:uuid:A37C3C73E994C267F11492530585522>
    // 
    // 	<the binary bytes of the zip start here...>
    // 

    // Load the binary response into a MIME object.
    CkMime mime;
    bool success = mime.LoadMimeBd(responseBody);
    if (success != true) {
        strOut.append(mime.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Make sure we have 2 sub-parts.  The 1st sub-part is the XML response, the 2nd sub-part
    // is the zip containing the data.

    // Note: The 2nd sub-part can be a "zip" or "gzip".  These are two different file formats.
    // A zip is indicated with a Content-Type header equal to "application/zip",
    // whereas a gzip is indicated with a Content-Type header equal to "application/x-gzip"
    if (mime.get_NumParts() != 2) {
        strOut.append("Expected the MIME to have 2 parts.");
        strOut.append("\r\n");
        strOut.append("NumParts = ");
        strOut.appendInt(mime.get_NumParts());
        strOut.append("\r\n");
        strOut.append("Failed.");
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Get the XML from the 1st MIME sub-part.
    CkMime *part0 = mime.GetPart(0);
    const char *downloadResponseXml = part0->getBodyDecoded();
    CkXml xmlResp;
    xmlResp.LoadXml(downloadResponseXml);
    strOut.append("Download Response XML:");
    strOut.append("\r\n");
    strOut.append(xmlResp.getXml());
    strOut.append("\r\n");
    delete part0;

    strOut.append("----");
    strOut.append("\r\n");

    // Now get the zip from the second part (index=1), unzip, and examine..
    CkMime *part1 = mime.GetPart(1);
    CkBinData zipData;
    // This example requires Chilkat v9.5.0.67 or later.
    // The GetBodyBd method was added in v9.5.0.67.
    part1->GetBodyBd(zipData);

    // Check to see if we have a zip or gzip.
    CkStringBuilder sbContentType;
    sbContentType.Append(part1->contentType());
    delete part1;

    CkXml xmlFromZip;

    if (sbContentType.Contains("gzip",false) == true) {
        // This is a gzip compressed file.
        CkGzip gzip;

        // in-place uncompress the data.
        // Note: The UncompressBd method was added in Chilkat v9.5.0.67
        success = gzip.UncompressBd(zipData);
        if (success != true) {
            strOut.append(gzip.lastErrorText());
            strOut.append("\r\n");
            SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
            return;
        }

        xmlFromZip.LoadXml(zipData.getString("utf-8"));

    }
    else {
        // This is a zip archive.

        // Load the body into a Zip object.
        CkZip zip;
        success = zip.OpenBd(zipData);
        if (success != true) {
            strOut.append(zip.lastErrorText());
            strOut.append("\r\n");
            SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
            return;
        }

        // Save the .zip to a file (so we can examine it for debugging if something is not as expected)
        zipData.WriteFile("qa_output/ebay_data.zip");

        // The zip should contain a single XML file.
        if (zip.get_NumEntries() != 1) {
            strOut.append("Expected the .zip to have 1 entry.");
            strOut.append("\r\n");
            strOut.append("NumEntries = ");
            strOut.appendInt(zip.get_NumEntries());
            strOut.append("\r\n");
            strOut.append("Failed.");
            strOut.append("\r\n");
            SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
            return;
        }

        CkZipEntry *entry = zip.GetEntryByIndex(0);

        xmlFromZip.LoadXml(entry->unzipToString(0,"utf-8"));
        delete entry;
    }

    strOut.append("XML contained in the zip:");
    strOut.append("\r\n");
    strOut.append(xmlFromZip.getXml());
    strOut.append("\r\n");
    strOut.append("----");
    strOut.append("\r\n");

    strOut.append("Success.");
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }