POST https://graph.microsoft.com/v1.0/subscriptions resulted in a 400 Bad Request

Question

Below is my code for subscribing notifications from outlook calendar webhooks. The code is not responding with validation token for the client side as unable to complete the POST subscribe request. Please help.

 $client = new \GuzzleHttp\Client();   
 $response = $client->post('https://graph.microsoft.com/v1.0/subscriptions', [
        'headers' => [
            'Authorization' => 'Bearer ' . $accessToken,
            'Content-Type' => 'application/json',
    ],
        'json' => [
            'changeType' => 'created,updated,deleted',
            'notificationUrl' =>  $notifcationUrl,
            'resource' => '/me/events', 
            'expirationDateTime' => $expirationDateTime, 
            'clientState' => '12345678',
        ],
    ]);

Answer 1

Hi @Shruti Malode

According to the Graph API, the notification endpoint must be able to respond to validation requests, and if validation fails, 400 error requests are returned.

See this link for more details:

https://learn.microsoft.com/en-us/graph/change-notifications-overview#notification-endpoint-validation

Hope this helps.

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