node.js application for speech recognition using Google Cloud Speech API
This application when deployed to Google App Engine will automatically authenticate to Google Firebase services like Realtime Database and Storage. However Google Cloud Messaging needs explicitly defining its API key. The API key is passed to application as env variable which is defined in app.yaml. The following commands allow you to update app.yaml env variable to a value which is stored in $GCM_SERVER_KEY.
$ GCM_SERVER_KEY=AAA
$ sed -i "s/GCM_SERVER_KEY:\(.*\)/GCM_SERVER_KEY: $GCM_SERVER_KEY/" app.yaml