For #177 : Support GCM&FCM "notification" payloads.

To start with, do the simplest possible thing and allow users to provide these as a JSON blob over the REST API.

E.g. the following (clients should obviously URL encode the values) uniqush.payload.fcm={"title":"MyTitle","body":"NotifBodyText"}

See the following links

https://firebase.google.com/docs/cloud-messaging/concept-options#notifications_and_data_messages -https://developers.google.com/cloud-messaging/concept-options#notifications_and_data_messages

"notification" payloads are rendered directly on the device by GCM, without needing the client apps to do anything (similar to APNS).

On a tangent, APNS now has silent notifications, and uniqush doesn't support those yet.

Example

Start a server

$ ./uniqush-push -config conf/uniqush-push.conf
[WebFrontend][Config] 2017/10/02 22:18:22 [Start] localhost:9898

Preview what Uniqush would send to FCM for the corresponding /push, within the field "payload" of the response (similar for GCM)

$ curl http://127.0.0.1:9898/previewpush \
    -d pushservicetype=fcm \
    -d 'uniqush.notification.fcm={"title":"my title","body":"notification body"}' \
    -d ttl=5
{"code":"UNIQUSH_SUCCESS","payload":{"notification":{"body":"notification body","title":"my title"},"registration_ids":["placeholderRegId"],"time_to_live":5}}

The push format is documented at the following links:

uniqush / uniqush-push

For #177 : Support GCM&FCM "notification" payloads. #185

Example