Integration of symfony 2 and google calendar

When you create a modern web project you can not do without working with external services. Recently, we had a task to work with calendars. In this article I would like to talk about some points of integrating a project on Symfony2 with Google Calendar.

Getting the key

To exchange data with google you need to get the key. Our site will ask for information unnoticed by the user, so we need a key for the account service. To get the key you need to go to the console for developers . Add an application, go to the Api tab and activate the calendar. Now you can get the key in the Credentials tab.
There is a json or p12 option. There is no particular difference, it depends on what is more convenient for you.

Google Api Module

To work with google services there is an api client . Install it through composer

php composer.phar require google / apiclient

We make a small wrapper and declare it as a service.

class Google { /* @var \Google_Client */ private $client; /* @var \Google_Service_Calendar */ private $calendar; private $scope; public function __construct($scope) { $this->client = new \Google_Client(); $this->scope = $scope; } public function setCredentialsP12($p12Path, $email) { $credentials = new \Google_Auth_AssertionCredentials( $email, $this->scope, file_get_contents($p12Path) ); $this->client->setAssertionCredentials($credentials); } public function setCredentialsJson($jsonPath) { $this->client->loadServiceAccountJson($jsonPath, $this->scope); } /** * @return \Google_Service_Calendar */ public function getCalendar() { if (!$this->calendar) { $this->calendar = new \Google_Service_Calendar($this->client); } return $this->calendar; } } 

 services: google.client: class: MyBundle\Google arguments: ['https://www.googleapis.com/auth/calendar.readonly'] #         

The setCredentialsP12 and setCredentialsJson methods are needed in order to transfer keys into our service. The getCalendar method returns the prepared calendar object and we do not need to somehow supplement it outside our service.
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Key Connection

We may have different keys in different environments, and each developer may have his own key. Therefore, we will transfer the key to the service depending on the presence of certain parameters that can be set in the local config. To do this, write and connect CompilerPass.

 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface; use Symfony\Component\DependencyInjection\ContainerBuilder; class CredentialsPass implements CompilerPassInterface { public function process(ContainerBuilder $container) { $googleClient = $container->getDefinition('google.client'); //        if ($container->hasParameter('google_p12_path') && $container->hasParameter('google_p12_email')) { $path = $container->getParameter('google_p12_path'); $email = $container->getParameter('google_p12_email'); $googleClient->addMethodCall('setCredentialsP12', [$path, $email]); } elseif ($container->hasParameter('google_json_path')) { $googleClient->addMethodCall('setCredentialsJson', [$container->getParameter('google_json_path')]); } } } 

And now it is enough for us to write in the local config.

 parameters: google_p12_path: my-certificate.p12 google_p12_email: my-email@mail.com 

or

 parameters: google_json_path: my-certificate.json 

Getting a list of events

Now we have a service and we can request a list of events.

 try { /* @var $start \DateTime */ $start; /* @var $end \DateTime */ $end; $events = $google->getCalendar()->events->listEvents('example@mail.com', [ 'timeMin' => $start->format('c'), 'timeMax' => $end->format('c'), ]); } catch (\Google_Service_Exception $exception) { //TODO implement error catching } 

Each calendar has its own unique email (example@mail.com in the example above). With the help of the listEvents method here we get all the events from our calendar for a certain period of time. Google uses the ISO 8601 standard for time parameters (timeMin, timeMax), so for formatting time it suffices to use the letter c.

Instead of conclusion

Spending a little time, we get access from our project to the google calendar. You can further develop this integration, for example, you can organize a more complex search or add events from our project. And if you are ready to entrust your calendars (and maybe not yours) to Google, then you can get a very powerful tool for cheap, which you can flexibly adjust to your needs.