Basic Withings fetch API written in PHP

---

• About the project
• Installation
• OAuth authentication
• Fetching resources
• License

About the project

This tiny project has been made to help people make requests to the main Withings API endpoints: Activity, Body, Sleep and Workouts.

It uses a standalone OAuth1 implementation, that might interest you if you are trying to understand how to sign an API request, for instance (that was the hard part for me).

Also, here are a few sample scripts, based on that library.

Installation

Download the source code and install it wherever you want in your project.

Then, require the files:

require 'path/to/the/library/src/autoload.php';

use WithingsFetcher\Error;
use WithingsFetcher\OAuth;
use WithingsFetcher\Fetcher;

Please note, since this library is considered to be still in WIP, it is not published on Composer.

OAuth authentication

To be able to fetch data from the Withings API, we need a valid access_token (and the associated secret).

Here are the steps we need to follow in order to get one.

Step 1. Get an authentication URL

$oauth = new OAuth(YOUR_API_KEY, YOUR_API_SECRET);
try
{
    $auth_url = $oauth->getAuthenticationURL('http://your-oauth-callback-url');
}
catch(Error $error)
{
    var_dump($error->getMessage());
}

Step 2. Validate the application

The user has to open the authentication URL in his browser, and accept the app.

When it's done, he will be redirected to http://your-oauth-callback-url?userid=1234567&oauth_token=....

• We will need his userid (that part is not covered by the API - you probably want to set the callback URL as an endpoint of your application, to extract the userid from the $_GET parameters)
• We don't need the other parameters contained in the callback URL

Step 3. Get the access token

When the app has been validated (the user has 2mns), we can generate an access token:

try
{
    $credentials = $oauth->generateAccessToken();
    var_dump($credentials);
    // array(3) {
    //     ["oauth_token"]=>
    //     string(60) "0c132bc6fc7bb253db02d2e424ef34018bb7fb30cb43bcbe1e1234512345"
    //     ["oauth_token_secret"]=>
    //     string(54) "d099592b25bcbde8b18240a657506c063f12345678901234567890"
    // }
}
catch(Error $error)
{
    var_dump($error->getMessage());
}

Once it has been issued, the access token should be stored (along with the user ID) and reused later.

Step 4. Reuse the access token

If we have stored an access_token and want to reuse it, instead of following the whole authentication process again, we can do so:

$oauth = new OAuth(YOUR_API_KEY, YOUR_API_SECRET);
$oauth->setAccessToken($stored_oauth_token, $stored_oauth_token_secret);

Fetching resources

Now we have a working $oauth object, with a valid access token, we can query public resources by using the Fetcher class.

Instanciate a new fetcher:

$fetcher = new Fetcher($oauth); // Please note the Fetcher needs our OAuth object

Then, the following methods are available:

$activity_measures = $fetcher->getActivityMeasures($params);

$body_measures = $fetcher->getBodyMeasures($params);

$sleep_measures = $fetcher->getSleepMeasures($params);

$sleep_summary = $fetcher->getSleepSummary($params);

$workout_measures = $fetcher->getWorkouts($params);

$params is an array of Withings API parameters (like startdate, enddate...).

A real-world example:

$measures = $fetcher->getActivityMeasures([
    'userid'       => '12345',
    'startdateymd' => '2015-12-01',
    'enddateymd'   => '2015-12-02',
]);
var_dump($measures);

// array(2) {
//   ["status"]=>
//   int(0)
//   ["body"]=>
//   array(1) {
//     ["activities"]=>
//     array(30) {
//       [0]=>
//       array(10) {
//         ["date"]=>
//         string(10) "2015-12-01"
//         ["steps"]=>
//         int(6)
//         ["distance"]=>
//         float(4.86)
//         ["calories"]=>
//         float(0.17)
//         ["totalcalories"]=>
//         float(1808.672)
//         ["elevation"]=>
//         int(0)
//         ["soft"]=>
//         int(0)
//         ["moderate"]=>
// ...

And that's it! Happy self-quantifying 🚀 🔍