Handler for highlight number & call bookmarklet (PHP)

phone_call_bookmarklet.php

<?php
# Example handler for "call selected number" phone call bookmarklet.
# Browser hits CGI with 2 phone numbers (action=dial).  Triggers outbound call 
# via cloudvox.com phone API.  When call connects, Cloudvox hits CGI for call 
# steps (action=answer).  CGI serves JSON to call 2nd number.
#  
# Browser bookmarklet example dial params:
#   action=dial&local_number=1234567890&remote_number=4567890123
# Cloudvox example answer params:
#   action=answer&phone_number=1234567890&remote_number=4567890123
# More: http://cloudvox.com/

header("Content-type: text/plain");
process_request($_GET['action'], $_GET['local_number'], $_GET['remote_number']);

function process_request($action, $local_number, $remote_number) {
  # dial URL for this app
  $dial_url = 'http://myhost.cloudvox.com/applications/42/dial';
  # API key or basic auth
  $dial_username = 'my@user.com';
  $dial_password = 'mypass';

  if ($action == 'dial') {
    # call the bookmarklet user
    print place_call($dial_url, $dial_username, $dial_password, $local_number, $remote_number);
  } elseif ($action == 'answer') {
    # local user has picked up. Generate steps to call remote number
    print make_call_steps($remote_number);
  }
}

function place_call($url, $username, $password, $local_number, $remote_number) {
  $url = "$url?phone_number=$local_number&remote_number=$remote_number";
  return(http_auth_get($url, $username, $password));
}

function make_call_steps($remote_number) {
  $steps = array(
    array('Name' => 'Speak', 'phrase' => 'Calling other party...'),
    array('Name' => 'Dial', 'number' => $remote_number)
  );
  return(json_encode($steps));
}

function http_auth_get($url, $username, $password) {
  $ctx = stream_context_create(basic_auth_for($username, $password));
  $handle = fopen($url, 'r', false, $ctx);

  return(stream_get_contents($handle));
}

function basic_auth_for($username, $password) {
  $cred = sprintf('Authorization: Basic %s', base64_encode("$username:$password"));
  $opts = array(
    'http' => array(
      'method' => 'GET',
      'header' => $cred)
    );
  return($opts);
}
?>