React Native

Azure Storage: Download Blob to File

See more Azure Cloud Storage Examples

Sample code to download an Azure blob to a file. React Native

import { AuthAzureStorage, Rest, Stream } from '@chilkat/react-native'

async function chilkatExample() {
  // This example requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  const rest = new Rest();

  // Connect to the Azure Storage Blob Service
  const bTls = true;
  const port = 443;
  const bAutoReconnect = true;
  // In this example, the storage account name is "chilkat".
  try {
    await rest.connectAsync('chilkat.blob.core.windows.net', port, bTls, bAutoReconnect);
  } catch {
    console.log(rest.lastErrorText);
    return;
  }

  // Provide Azure Cloud credentials for the REST call.
  const azAuth = new AuthAzureStorage();
  azAuth.accessKey = 'AZURE_ACCESS_KEY';
  // The account name used here should match the 1st part of the domain passed in the call to Connect (above).
  azAuth.account = 'chilkat';
  azAuth.scheme = 'SharedKey';
  azAuth.service = 'Blob';
  // This causes the "x-ms-version: 2021-08-06" header to be automatically added.
  azAuth.xMsVersion = '2021-08-06';
  rest.setAuthAzureStorage(azAuth);

  // Note: The application does not need to explicitly set the following
  // headers: Content-Length, x-ms-date, Authorization.  These headers
  // are automatically set by Chilkat.

  // Setup a file stream for the download
  const fileStream = new Stream();
  fileStream.sinkFile = 'C:/temp/qa_output/starfish.jpg';

  // Indicate that the call to FullRequestNoBody should send the response body
  // to fileStream if the response status code is 200.
  // If a non-success response status code is received, then nothing
  // is streamed to the output file and the error response is returned by FullRequestNoBody.
  const expectedStatus = 200;
  rest.setResponseBodyStream(expectedStatus, true, fileStream);

  // The Azure blob container is "test", the file is "starfish.jpg"
  let responseStr = '';
  try {
    responseStr = await rest.fullRequestNoBodyAsync('GET', '/test/starfish.jpg');
  } catch {

    // Examine the request/response to see what happened.
    console.log(`response status code = ${rest.responseStatusCode}`);
    console.log(`response status text = ${rest.responseStatusText}`);
    console.log(`response header: ${rest.responseHeader}`);
    console.log(`response body (if any): ${responseStr}`);
    console.log('---');
    console.log(`LastRequestStartLine: ${rest.lastRequestStartLine}`);
    console.log(`LastRequestHeader: ${rest.lastRequestHeader}`);
    return;
  }

  console.log('Success.');
}