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c2dm sends push notifications to Android devices via google c2dm.
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c2dm sends push notifications to Android devices via Google Cloud Messaging (GCM).


$ gem install c2dm


An Android device running 2.2 or newer, its registration token, and a GCM api key.


There are two ways to use c2dm.

Sending many individual notifications using a static method:

notifications = [
    registration_id: "...1", 
    data: {
      some_message: "Some payload",
      a_value: 10
    collapse_key: "foobar" #optional
    registration_id: "...2", 
    data: {
      some_message: "Some other payload",
      a_value: 20

C2DM.api_key = "YourGCMApiKey" # This initializes all future instances of C2DM with "YourGCMApiKey"

Sending this way will not raise an error but send_notifications will return an array of hashes including the registration_id and the response. If GCM returns an error while C2DM is sending one of the notifications, the response in the hash of the appropriate notification will be an object of type C2DM::GCMError.

...or one at a time by creating an instance:

c2dm ="YourGCMApiKey")
data = {some_message: "Some payload", a_value: 10}
collapse_key = "optional_collapse_key"
c2dm.send_notification("aRegistrationId", data, collapse_key)

Sending using an instance of C2DM will raise a C2DM::GCMError error when sending fails.


  • Copyright (c) 2010-2012 Amro Mousa. See LICENSE.txt for details.


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