Yesterday I decided that I’m going to extend the functionality of my “learn words” application. With the new functionality the user will be able to listen to a given word or expression and I hope this way it will be more easier to learn the words and expressions. I didn’t know where to start writing the backend part, but I knew a service which provides such a functionality and this is the google translate. I took a look at the network panel in my browsers console and started to investigate if google forbids an akin request from a different domain. Luckily they don’t, so I set myself to patch the code. And here is the result! Feel free to use the class! Any feedback is appreciated.
P.s.: I hope it’s allowed to use the service even though the guys at google don’t forbid it, but if it’s not the case, just ping me and I try to find another solution.
Usage:
<?php
require_once 'ReadIt.class.php';
// The text can be passed to the constructor
// or to the setText method
$r = new ReadIt('Valami');
// You can change on the language by passing
// the 2 character country code to this method
$r->setLanguage('hu');
// Push the data back to the browser (or cli)
$r->readIt();
// Or write out data into a file
$r->writeIt('filename.mpeg');
?>
Class’s code:
<?php
/**
* Helper class to read up a text with the Google Translate's service
*
* Copyright (C) 2013 Gabor Szabo <szabo.gabor@szabogabor.net>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
class ReadIt
{
const BASE_URL = 'http://translate.google.com/translate_tts';
const DEFAULT_LANGUAGE = 'en';
/**
* Sets the proper headers if the result
* will be redirected to the standard output
*
* @return void
*/
private function setHeaders()
{
header('Cache-Control:private, max-age=86400');
header('Content-Length:' . strlen($this->response));
header('Content-Type:audio/mpeg');
return $this;
}
/**
* Return with the GET parameters of the request
*
* @return string The urlencoded parameters
*/
private function getParameters()
{
$parameters = array(
'ie' => 'UTF-8',
'q' => $this->text,
'tl' => $this->getLanguage(),
'total' => '1',
'idx' => '0',
'textlen' => strlen($this->text),
'prev' =>'input'
);
return http_build_query($parameters);
}
/**
* Return with the given language or the pre-defined
* default language if was not given
*
* @return string The language code
*/
private function getLanguage()
{
if(!empty($this->language))
{
return $this->language;
}
return self::DEFAULT_LANGUAGE;
}
public function __construct($text = NULL)
{
if(!function_exists('curl_init'))
{
throw new Exception('You must install cURL module to be able to use the class!');
}
if( $text !== NULL )
{
$this->setText($text);
}
}
/**
* Sets the text what will be read up in the audio file
*
* @param string|array $text The text
*/
public function setText($text)
{
if(empty($text))
{
throw new Exception('The text cannot be empty!');
}
if(is_array($text))
{
$text = implode('', $text);
}
$this->text = $text;
return $this;
}
/**
* Sets the language code
*
* @param string $lang The 2 character length code of the language
* @return void
*/
public function setLanguage($lang)
{
if(empty($lang))
{
throw new Exception('The language code cannot be empty!');
}
$this->language = $lang;
return $this;
}
/**
* Performs the cURL request and returns
* with the raw response
*
* @return string The response of the service
*/
private function doRequest()
{
$curlRequest = curl_init();
curl_setopt($curlRequest, CURLOPT_URL, self::BASE_URL . '?' . $this->getParameters());
curl_setopt($curlRequest, CURLOPT_HTTPGET, true);
curl_setopt($curlRequest, CURLOPT_RETURNTRANSFER, 1);
$response = curl_exec($curlRequest);
$error = curl_error($curlRequest);
$returnCode = curl_getinfo($curlRequest, CURLINFO_HTTP_CODE);
curl_close($curlRequest);
if(!empty($error) || $returnCode !== 200)
{
throw new Exception('Error occured during the request!');
}
return $response;
}
/**
* Sets the proper headers and writes the
* audio data to the standard output
*
* @return void
*/
public function readIt()
{
if(empty($this->text))
{
throw new Exception('You must give a text to read!');
}
$this->response = $this->doRequest();
$this->setHeaders();
echo $this->response;
return $this;
}
/**
* Writes the audio data into a file
*
* @param string $filename The filename to write the result into
* @return void
*/
public function writeIt($filename)
{
if($filename === NULL)
{
throw new Exception('Filename cannot be empty!');
}
$this->response = $this->doRequest();
if(file_put_contents($filename, $this->response) === false)
{
throw new Exception('Failed to write out the response into the file!');
}
return $this;
}
}
?>
