Set API key and sender ID values in this file which defined as macros.

Compile rebar project:

./rebar3 compile

Run Erlang console with our compiled beam files:

erl -pa  _build/default/lib/*/ebin/

In Erlang console, run commands below. There will be messages displayed.

gcm_xmpp:start_link().
gcm_xmpp:send("hello", "device-token-here").