React Native

HTTP POST and Stream Response to File

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Demonstrates how to send an HTTP POST and stream the response body directly to a file. React Native

import { Rest, Stream, Url } 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();

  const url = new Url();
  // This URL will emit a response that echos the query params (name and age)
  url.parseUrl('https://www.chilkatsoft.com/readPost.asp');

  // Connect to the web server
  const bAutoReconnect = true;
  try {
    await rest.connectAsync(url.host, url.port, url.ssl, bAutoReconnect);
  } catch {
    console.log(rest.lastErrorText);
    return;
  }

  rest.addQueryParam('name', 'John');
  rest.addQueryParam('age', '33');

  //  Send the HTTP POST.
  try {
    await rest.sendReqFormUrlEncodedAsync('POST', url.path);
  } catch {
    console.log(rest.lastErrorText);
    return;
  }

  // Read the response header.
  const responseStatusCode = await rest.readResponseHeaderAsync();
  if (responseStatusCode < 0) {
    console.log(rest.lastErrorText);
    return;
  }

  console.log(`Response status code = ${responseStatusCode}`);

  // We expect a 200 response status if the file data is coming.
  // Otherwise, we'll get a string response body with an error message(or no response body).
  if (responseStatusCode === 200) {

    const bodyStream = new Stream();

    // The stream's sink will be a file.
    bodyStream.sinkFile = 'qa_output/out.txt';

    // Read the response body to the stream.  Given that we've
    // set the stream's sink to a file, it will stream directly
    // to the file.
    try {
      await rest.readRespBodyStreamAsync(bodyStream, true);
    } catch {
      console.log(rest.lastErrorText);
      return;
    }

    console.log('Successfully streamed the response to a file.');
  } else {
    try {
      const errResponse = await rest.readRespBodyStringAsync();
      console.log(errResponse);
    } catch {
      console.log(rest.lastErrorText);
    }
  }
}