title: Cordova Push + Azure Notification Hub
body: <p>I'm trying to connect my ionic + cordova based hybrid app to Azure Notification Hub (ANH). For now I only have GCM credentials but the purpose is to register APNS credentials soon.</p>
  
  <p>It seems that there are different solutions to connect to ANH via a Cordova App:</p>
  
  <ul>
  <li>A cordova plugin: <a href="https://github.com/sgrebnov/cordova-plugin-azure-notificationhub" rel="nofollow">https://github.com/sgrebnov/cordova-plugin-azure-notificationhub</a>: did someone already use this? Are there any prerequisites (phonegap-push-plugin for example)?</li>
  <li>The ANH REST API: <a href="https://msdn.microsoft.com/en-us/library/azure/dn495627.aspx" rel="nofollow">https://msdn.microsoft.com/en-us/library/azure/dn495627.aspx</a> and <a href="https://msdn.microsoft.com/en-us/library/azure/dn223265.aspx" rel="nofollow">https://msdn.microsoft.com/en-us/library/azure/dn223265.aspx</a>: I tried to do a POST to the CreateRegistration endpoint with the data required for Native GCM messages. However I always get a 400 with this error message in the response: <strong>"An invalid tag 'System.Collections.Generic.HashSet`1[System.String]' was supplied. Valid tag characters are alphanumeric, _, @, -, ., : and #."</strong> It seems to be related to the {GCM Registration Id} I'm passing. Whatever I provide, it returns that error. Anyone knows the format of a valid GCM registration id that can be provided to this API?</li>
  </ul>