DeepLy

DeepL.com is a great, new translation service. It provides better translations compared to other popular translation engines. DeepLy is a PHP package that implements a client to interact with DeepL via their undocumented API and without an API key. Please switch to DeepLy 2 if you have an API key.

Installation

Through Composer:

composer require chriskonnertz/deeply

From then on you may run composer update to get the latest version of this library.

It is possible to use this library without using Composer but then it is necessary to register an autoloader function.

This library requires PHP 5.6 or higher and the cURL extension.

Usage Example

$deepLy = new ChrisKonnertz\DeepLy\DeepLy();

$translatedText = $deepLy->translate('Hello world!', 'DE', 'EN');
    
echo $translatedText; // Prints "Hallo Welt!"

An interactive PHP demo script is included. It is located at demos/demo_translate.php.

Sophisticated Example

use ChrisKonnertz\DeepLy\DeepLy;

$deepLy = new DeepLy();

try {
    $translatedText = $deepLy->translate('Hello world!', DeepLy::LANG_EN, DeepLy::LANG_AUTO);
    
    echo $translatedText; // Prints "Hallo Welt!"
} catch (\Exception $exception) {
    echo $exception->getMessage();
}

Always wrap calls of the translate method in a try-catch-block, because they might throw an exception if the arguments are invalid or the API call fails. Instead of using hardcoded strings as language arguments better use the language code constants of the DeepLy class. The class also offers methods such as getLangCodes($withAuto = true) and supportsLangCode($langCode).

You may use the proposeTranslations method if you want to get alternative translations for a text. This method cannot operate on more than one sentence at once.

Auto-Detect Language

DeepLy has a method that uses the DeepL API to detect the language of a text:

$languageCode = $deepLy->detectLanguage('Hello world!');

This will return 'EN'. The language of the text has to be one of the supported languages or the result will be incorrect. If you do not need the code of the language but its name, you may call the $deepLy->getLangName($langCode) method.

The API in general can handle and completely translate texts that contain parts with different languages, if the language switch is not within a sentence. The detectLanguage() method will however only return the code of one language. It will throw an exception if it is unable to auto-detect the language. This will rarely happen, it is more likely that the API will return a "false positive": It will rather detect the wrong language than no language at all.

An interactive PHP demo script is included. It is located at demos/demo_detect.php.

Supported Languages

DeepL(y) supports these languages:

Code	Language
auto	Auto detect
DE	German
EN	English
FR	French
ES	Spanish
IT	Italian
NL	Dutch
PL	Polish

Note that auto detection only is possible for the source language.

DeepL says they will add more languages in the future, such as Chinese and Russian.

Text Length Limit

According to the DeepL.com website, the length of the text that has to be translated is limited to 5000 characters. Per default DeepLy will throw an exception if the length limit is exceeded. You may call $deepLy->setValidateTextLength(false) to disable this validation.

HTTP Client

Per default DeepLy uses a minimalistic HTTP client based on cURL. If you want to use a different HTTP client, such as Guzzle, create a class that implements the HttpClient\HttpClientInterface and makes use of the methods of the alternative HTTP client. Then use $deepLy->setHttpClient($yourHttpClient) to inject it.

Note: If you experience issues with the integrated cURL client that could be solved by setting the CURLOPT_SSL_VERIFYPEER to false, first read this: snippets.webaware.com.au/../

If it does not help try: $deepLy->getHttpClient()->setSslVerifyPeer(false)

Guzzle

If you want to use Guzzle as the HTTP client: Support for Guzzle is available out-of-the-box. Make sure you have installed Guzzle (preferably via Composer), then copy this code and paste it right after you instantiate DeepLy:

$protocol = $deepLy->getProtocol();
$httpClient = new \ChrisKonnertz\DeepLy\HttpClient\GuzzleHttpClient($protocol);
$deepLy->setHttpClient($httpClient);

Framework Integration

DeepLy comes with support for Laravel 5.x and since it also supports package auto-discovery it will be auto-detected in Laravel 5.5.

In Laravel 5.0-5.4 you manually have to register the service provider ChrisKonnertz\DeepLy\Integrations\Laravel\DeepLyServiceProvider in the "providers" array and the facade ChrisKonnertz\DeepLy\Integrations\Laravel\DeepLyFacade as an alias in the "aliases" array in your config/app.php config file.

You can then access DeepLy like this: $ping = \DeepLy::ping();

Demos

There are several demo scripts included in the demos folder:

demo_detect.php: Demonstrates language detection. Write a text and the API will tell you which language it thinks it is.
demo_translate.php: Demonstrates language translation. Write a text and the API will try to translate it to a language of your choice.
demo_split.php: Demonstrates sentence detection. Write a text and the API will split it into sentences.
demo_ping.php: Demonstrates DeepLy's ping() method by pinging the API.

Request Limit

There is a request limit. The threshold of this limit is unknown.

Internals

The "core" of this library constists of these classes:

DeepLy - main class
HttpClient\CurlHttpClient - HTTP client class
Protocol\JsonRpcProtocol - JSON RPC is the protocol used by the DeepL API
ResponseBag\AbstractBag - base wrapper class for the responses of the DeepL API
ResponseBag\SentencesBag - concrete class for API responses to "split text" requests
ResponseBag\TranslationBag - concrete class for API responses to "translate" requests

There are also some exception classes, interfaces, an alternative HTTP client implementation that uses Guzzle and classes for the Laravel integration.

Current State

I do not know when DeepL.com will officially release their API (it is in beta state right now) but I expect them to do it within the next weeks. The API will require authentication with an API key. This will be supported by Deeply 2. Until then you may use DeepLy 1.x on your own risk.

Also note that their API responds quite slow. This might be intentional. Nevertheless the API is reliable. I had not a single failing call amongst hundreds of API calls.

Disclaimer

This is not an official package. It is 100% open source and non-commercial. The API of DeepL.com is free as well but this might change in the future. It remains unclear what this exactly means.

DeepL is a product from DeepL GmbH. More info: deepl.com/publisher.html

This package has been heavily inspired by node-deepls and deeplator. Thank you for your great work! Give these implementations a try if you are coding in Node.js or Python.

Notes

If you are looking for a real-world example application that uses DeepLy, you may take a look at Translation Factory.
The code of this library is formatted according to the code style defined by the PSR-2 standard.
Status of this repository: Maintained. Create an issue and you will get a response, usually within 48 hours.

glemmal/DeepLy