React Native Requires Chilkat v11.0.0+

eBay -- Download Data using FileTransferService

See more eBay Examples

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

import { BinData, Gzip, Http, HttpRequest, HttpResponse, Mime, StringBuilder, Xml, Zip, ZipEntry } from '@chilkat/react-native'

async function chilkatExample() {
  // 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 accessToken = 'EBAY_ACCESS_TOKEN';

  const http = new Http();

  const req = new HttpRequest();

  req.httpVerb = 'POST';
  req.path = '/FileTransferService';
  req.contentType = 'application/xml';

  // Build the XML body for the request.
  const xml = new Xml();
  xml.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);

  const resp = new HttpResponse();
  try {
    await http.httpSReqAsync('storage.sandbox.ebay.com', 443, true, req, resp);
  } catch {
    console.log(http.lastErrorText);
    return;
  }

  const statusCode = resp.statusCode;
  console.log(`Response status code = ${statusCode}`);

  const responseBody = new BinData();
  resp.getBodyBd(responseBody);

  // 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) {
    console.log('Failed.');
    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.
  const mime = new Mime();
  try {
    mime.loadMimeBd(responseBody);
  } catch {
    console.log(mime.lastErrorText);
    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.numParts !== 2) {
    console.log('Expected the MIME to have 2 parts.');
    console.log(`NumParts = ${mime.numParts}`);
    console.log('Failed.');
    return;
  }

  // Get the XML from the 1st MIME sub-part.

  const part0 = new Mime();
  try {
    mime.partAt(0, part0);
  } catch {
    console.log(mime.lastErrorText);
    return;
  }

  const downloadResponseXml = part0.getBodyDecoded();
  const xmlResp = new Xml();
  xmlResp.loadXml(downloadResponseXml);
  console.log('Download Response XML:');
  console.log(xmlResp.getXml());

  console.log('----');

  // Now get the zip from the second part (index=1), unzip, and examine..

  const part1 = new Mime();
  try {
    mime.partAt(1, part1);
  } catch {
    console.log(mime.lastErrorText);
    return;
  }

  const zipData = new BinData();
  part1.getBodyBd(zipData);

  // Check to see if we have a zip or gzip.
  const sbContentType = new StringBuilder();
  sbContentType.append(part1.contentType);

  const xmlFromZip = new Xml();

  if (sbContentType.contains('gzip', false)) {
    // This is a gzip compressed file.
    const gzip = new Gzip();

    // in-place uncompress the data.
    // Note: The UncompressBd method was added in Chilkat v9.5.0.67
    try {
      await gzip.uncompressBdAsync(zipData);
    } catch {
      console.log(gzip.lastErrorText);
      return;
    }

    xmlFromZip.loadXml(zipData.getString('utf-8'));
  } else {
    // This is a zip archive.

    // Load the body into a Zip object.
    const zip = new Zip();
    try {
      zip.openBd(zipData);
    } catch {
      console.log(zip.lastErrorText);
      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.numEntries !== 1) {
      console.log('Expected the .zip to have 1 entry.');
      console.log(`NumEntries = ${zip.numEntries}`);
      console.log('Failed.');
      return;
    }

    const entry = new ZipEntry();
    try {
      zip.entryAt(0, entry);
    } catch {
      console.log(zip.lastErrorText);
      return;
    }

    xmlFromZip.loadXml(await entry.unzipToStringAsync(0, 'utf-8'));
  }

  console.log('XML contained in the zip:');
  console.log(xmlFromZip.getXml());
  console.log('----');

  console.log('Success.');
}