what does gcm.notification.e=1 stand for, into push notification payload on Android?

Question

I'm writing an Android application which receives downstream messages from a server using Google Cloud Messaging. When receiving a message with onMessageReceived I print the bundle and read this:

RECEIVED PUSH NOTIFICATION: Bundle[{gcm.notification.e=1, gcm.notification.badge=1, gcm.notification.sound=default, ..etc...

I don't understand the key gcm.notification.e in the notification payload. On Google documentation I didn't find anything like that. Moreover, when sending the message, I usually specify both a notification payload and a data payload. Now I tried to remove the notification payload but I still receive gcm.notification.e=1

Someone can help me understand this key and find a way to remove it? Thanks

EDIT: I found out that sending a message without the notification payload and with content_available=false (I set this to true when working with iOS) then the gcm.notification.e=1 is not received. I receive only the data payload :). However, I still want to know the meaning of this e

Answer 1

Maybe this e field stands for enable. If you set it to zero in your server you won't receive the notification payload on Android. For more details se my answer here.