Pushex
Pushex is a library to easily send push notifications with Elixir.
About
Goals
The main goals are the following:
- Easy to use async API
- Common API for iOS and Android
- Multiple applications handling
- Proper error and response handling
- Testable using a sanbox mode
Status
Both GCM and APNS are working. APNS delegates to apns4ex for now, I will probably use the HTTP2 API in a later version.
The API is still subject to change, with a minor version bump for each change.
Installation
Add the following to your dependencies mix.ex.
[{:pushex, "~> 0.2"}]
Then, add :pushex
to your applications.
Usage
The most basic usage, with no configuration looks like this:
app = %Pushex.GCM.App{name: "a_unique_name_you_like", auth_key: "a GCM API auth key"}
Pushex.push(%{title: "my_title", body: "my_body"}, to: "registration_id", with_app: app)
To avoid having to create or retreive your app each time, you can configure as many apps
as you want in your config.exs
:
config :pushex,
gcm: [
default_app: "first_app",
apps: [
[name: "first_app", auth_key: "a key"],
[name: "other_app", auth_key: "another key"]
]
],
apns: [
default_app: "first_app",
apps: [
[name: "first_app", env: :dev, certfile: "/path/to/certfile", pool_size: 5]
]
]
You can then do the following:
# this will use the default app, "first_app" with the above configuration
Pushex.push(%{title: "my_title", body: "my_body"}, to: "registration_id", using: :gcm)
# this will use the other_app
Pushex.push(%{title: "my_title", body: "my_body"}, to: "registration_id", using: :gcm, with_app: "other_app")
Note that the function is async and only returns a reference, see the response and error handling documentation for more information.
Sending to multiple platforms
If you want to use the same message for both platforms, you can define messages as follow:
message = %{
common: "this will be in both payloads",
other: "this will also be in both payloads",
apns: %{
alert: "My alert",
badge: 1
},
gcm: %{
title: "GCM title",
body: "My body"
}
}
Pushex.push(message, to: ["apns_token1", "apns_token2"], using: :apns)
Pushex.push(message, to: ["gcm_registration_id1", "gcm_registration_id2"], using: :gcm)
Only :gcm
and :apns
are currently available.
Passing more options
If you need to pass options, priority
for example, you can just pass
it in the keyword list and it will be sent.
See
https://developers.google.com/cloud-messaging/http-server-ref#downstream-http-messages-json
for more information.
The parameters from Table 1
should be passed in the keyword list, while
the parameters from Table 2
should be passed in the first argument.
For more information about APNS
options, see apns4ex docs.
NOTE: if you pass an array to the to
parameter, if will automatically
be converted to registration_ids
when sending the request, to keep a consistent API.
Loading app from somewhere else
If you are saving your auth_keys in your database, you can override the default way to retreive the apps:
# config.exs
config :pushex,
app_manager_impl: MyAppManager
# my_app_manager.ex
defmodule MyAppManager do
@behaviour Pushex.AppManager
def find_app(platform, name) do
if app = Repo.get_by(App, platform: platform, name: name) do
make_app(platform, app)
end
end
# transform to a `Pushex._.App`
defp make_app(:gcm, app) do
struct(Pushex.GCM.App, Map.from_struct(app))
end
defp make_app(:apns, app) do
struct(Pushex.APNS.App, Map.from_struct(app))
end
end
Handling responses
To handle responses, you can define a module using Pushex.EventHandler
which uses :gen_event
to process events.
# config.exs
config :pushex,
event_handlers: [MyEventHandler]
# my_event_handler.ex
defmodule MyEventHandler do
use Pushex.EventHandler
def handle_event({:request, request, {pid, ref}}, state) do
# do whatever you want with the request
# for example, logging or saving in a DB
{:ok, state}
end
def handle_event({:response, response, request, {pid, ref}}, state) do
# do whatever you want with the response and request
{:ok, state}
end
end
The ref
passed here is the one returned when calling push
.
Testing
Pushex offers a sandbox mode to make testing easier.
To enable it, you should add the following to your configuration:
config :pushex,
sandbox: true
Once you are using the sandbox, the messages will not be sent to GCM or APNS anymore,
but stored in Pushex.Sandbox
. Furthermore, all the messages will be returned
to the process that sent them.
Here is a sample test.
test "send notification to users" do
ref = Pushex.push(%{body: "my message"}, to: "my-user", using: :gcm)
pid = self()
assert_receive {{:ok, response}, request, ^ref}
assert [{{:ok, ^response}, ^request, {^pid, ^ref}}] = Pushex.Sandbox.list_notifications
end
Note that list_notifications
depends on the running process, so
if you call it from another process, you need to explicitly pass the pid with the :pid
option.
Also note that Pushex.push
is asynchronous, so if you
remove the assert_receive
, you will have a race condition.
To avoid this, you can use Pushex.Sandbox.wait_notifications/1
instead of Pushex.Sandbox.list_notifications
.
It will wait (by default for 100ms
) until at least :count
notifications arrive
test "send notification to users and wait" do
Enum.each (1..10), fn _ ->
Pushex.push(%{body: "foo"}, to: "whoever", using: :gcm)
end
notifications = Pushex.Sandbox.wait_notifications(count: 10, timeout: 50)
assert length(notifications) == 10
end
However, the requests are asynchronous, so there is no guaranty that the notifications in the sandbox will in the same order they have been sent.