insomnia-node-libcurl/examples/send-method.js

Node bindings for libcurl. Based on the work from node-curl.

/**
 * @author Jonathan Cardoso Machado
 * @license MIT
 * @copyright 2015-2016, Jonathan Cardoso Machado
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do
 * so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/**
 * This is an example showing how one could use the send and recv methods
 */
var Easy = require('../lib/Easy'),
  Multi = require('../lib/Multi'),
  Curl = require('../lib/Curl'),
  easy = new Easy(),
  multi = new Multi(),
  send = new Buffer('GET / HTTP/1.0\r\nHost: example.com\r\n\r\n'),
  recv = new Buffer(5 * 1024 * 1024), //reserve 5mb
  isSent = false,
  shouldUseMultiHandle = true;

recv.fill(0);

easy.setOpt(Curl.option.URL, 'http://example.com');
// CONNECT_ONLY must be set to send and recv work
easy.setOpt(Curl.option.CONNECT_ONLY, true);

//This callback is going to be called when there is some action
// in the socket responsible for this handle.
// Remember that, for it to be called, one must have called easy.monitorSocketEvents();
easy.onSocketEvent(function(err, events) {
  var ret,
    isWritable = events & Easy.socket.WRITABLE,
    isReadable = events & Easy.socket.READABLE;

  if (err) {
    throw err;
  }

  // Make sure the socket is writable, and, that we have not sent the request already.
  if (isWritable && !isSent) {
    console.log('Sending request.');
    ret = easy.send(send);

    // ret is an array, with [0] being returnCode, and [1] the number of bytes sent.

    // just lets make sure the returnCode is correct and that all the data was sent.
    if (ret[0] !== Curl.code.CURLE_OK || ret[1] !== send.length) {
      throw Error('Something went wrong.');
    }

    console.log('Sent ' + ret[1] + ' bytes.');

    isSent = true;

    // Here we must check if the socket is readable, and that we have sent the data already.
  } else if (isReadable && isSent) {
    console.log('Reading request response.');
    ret = easy.recv(recv);

    //same than above, but [1] now is the number of bytes we have read.

    if (ret[0] !== Curl.code.CURLE_OK) {
      throw Error(Easy.strError(ret[0]));
    }

    console.log(recv.toString('utf8', 0, ret[1]));

    //we don't need to monitor for events anymore, so let's just stop the socket polling
    this.unmonitorSocketEvents();

    if (shouldUseMultiHandle) {
      multi.removeHandle(easy);
      multi.close();
    }

    easy.close();
  }
});

//send and recv only works with the multi handle
// if you are using a libcurl version greater than 7.42
// See: https://github.com/bagder/curl/commit/ecc4940df2c286702262f8c21d7369f893e78968
if (shouldUseMultiHandle) {
  multi.onMessage(function(err, easy, errorCode) {
    if (err) {
      console.error('Error code: ' + errorCode);

      throw err;
    }

    //ok, connection made!
    // monitor for socket events
    easy.monitorSocketEvents();
  });

  multi.addHandle(easy);
} else {
  var result = easy.perform();

  if (result !== Curl.code.CURLE_OK) {
    throw Error(Easy.strError(result));
  }

  //Using just the easy interface,
  // the connection is made right after the perform call
  // so we can already start monitoring for socket events
  easy.monitorSocketEvents();
}