Andpush 
Andpush is an HTTP client for FCM (Firebase Cloud Messaging). It implements the Firebase Cloud Messaging HTTP Protocol.
The andpush gem performs about 3.7x faster than the fcm gem in a single-threaded environment.
If you are thinking to send push notifications from Rails, consider using the pushing gem, a push notification framework that does not hurt.
Installation
Add this line to your application's Gemfile:
gem 'andpush'
Or install it yourself as:
$ gem install andpush
Usage
You'll need your application's server key, whose value is available in the Cloud Messaging tab of the Firebase console Settings pane.
require 'andpush'
server_key = "..." # Your server key
device_token = "..." # The device token of the device you'd like to push a message to
client = Andpush.new(server_key, pool_size: 25)
payload = {
to: device_token,
notification: {
title: "Update",
body: "Your weekly summary is ready"
},
data: { extra: "data" }
}
response = client.push(payload)
headers = response.headers
headers['Retry-After'] # => returns 'Retry-After'
json = response.json
json[:canonical_ids] # => 0
json[:failure] # => 0
json[:multicast_id] # => 8478364278516813477
result = json[:results].first
result[:message_id] # => "0:1489498959348701%3b8aef473b8aef47"
result[:error] # => nil, "InvalidRegistration" or something else
result[:registration_id] # => nil
Topic Messaging:
topic = "/topics/foo-bar"
payload = {
to: topic,
data: {
message: "This is a Firebase Cloud Messaging Topic Message!",
}
}
response = client.push(payload) # => sends a message to the topic
Using HTTP/2 (Experimental)
The current GitHub master branch ships with experimental support for HTTP/2. It takes advantage of the fantastic library, libcurl. In order to use it, replace Andpush.new(...) with Andpush.http2(...):
+# Do not forget to add the curb gem to your Gemfile
+require 'curb'
-client = Andpush.new(server_key, pool_size: 25)
+client = Andpush.http2(server_key) # no need to specify the `pool_size' as HTTP/2 maintains a single connection
Prerequisites
Make sure that your production environment has the compatible versions installed. If you are not sure what version of libcurl you are using, try running curl --version and make sure it has HTTP2 listed in the Features:
If you wish to use the HTTP/2 client in heroku, make sure you are using the Heroku-18 stack. Older stacks, such as Heroku-16 and Cedar-14 do not ship with a version of libcurl that has support for HTTP/2.
If you are using an older version of libcurl that doesn't support HTTP/2, don't worry. It will just fall back to HTTP 1.1 (of course without header compression and multiplexing.)
Performance
The andpush gem uses HTTP persistent connections to improve performance. This is done by the net-http-persistent gem. A simple benchmark shows that the andpush gem performs at least 3x faster than the fcm gem:
$ ruby bench.rb
Warming up --------------------------------------
andpush 2.000 i/100ms
fcm 1.000 i/100ms
Calculating -------------------------------------
andpush 28.009 (± 7.1%) i/s - 140.000 in 5.019399s
fcm 7.452 (±13.4%) i/s - 37.000 in 5.023139s
Comparison:
andpush: 28.0 i/s
fcm: 7.5 i/s - 3.76x slower
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/yuki24/andpush. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
License
The gem is available as open source under the terms of the MIT License.