Apus

Apus is an Elixir library enabling a flexible and testable approach to sending SMS messages.

Installation

You can install apus by adding it to your list of dependencies in mix.exs and running mix deps.get.

def deps do
  [
    {:apus, "~> 0.7.0"}
  ]
end

Getting Started

To get started using apus you must first setup a module that will handle sending sms messages.

defmodule MyApp.SmsSender do
  use Apus.SmsSender, otp_app: :my_app
end

Once the SmsSender module has been created it can be configured to use an adapter in your config/config.exs file.

config :my_app, MyApp.SmsSender,
  adapter: Apus.TwilioAdapter,
  account_sid: "<twilio account sid>",
  auth_token: "<twilio auth token>"

Now we can send sms messages like so.

message = %Apus.Message{
  to: "+15551234567",
  from: "+15557654321",
  body: "Hello there!"
}

# to deliver a message synchronously
MyApp.SmsSender.deliver_now(message)

# to deliver in the background
MyApp.SmsSender.deliver_later(message)

Working in development mode

When working in development we don't always want to send real SMS messages but we do want to see that they have been correctly sent through apus. To solve this, apus offers an in-memory adapter that can be configured in your config/dev.exs file.

config :my_app, MyApp.SmsSender, adapter: Apus.LocalAdapter

You will now see the sent messages being printed to the current terminal session as they are delivered.

Sent messages viewer

Apus comes with a built-in web interface for viewing sent messages via a plug. This interface works directly with the Apus.LocalAdapter which must be configured before using the sent messages viewer.

Using with Plug

defmodule MyApp.Router do
  use Plug.Router

  if Mix.env == :dev do
    forward("/sent_messages", to: Apus.SentMessagesViewerPlug)
  end
end

Using with Phoenix

defmodule MyApp.Router do
  use Phoenix.Router

  if Mix.env == :dev do
    forward("/sent_messages", Apus.SentMessagesViewerPlug)
  end
end

Testing

Apus comes with an Apus.TestAdapter and some handy macros to make testing SMS delivery straightforward.

Setup the test adapter in the config/test.exs file.

config :my_app, MyApp.SmsSender, adapter: Apus.TestAdapter

Now you can test SMS delivery using the assert_delivered_message macro.

Assertions

For full match use the following example:

defmodule MyApp.RegistrationTest do
  use ExUnit.Case

  import Apus.Test
  alias Apus.Message

  test "the user gets a message after registration" do
    new_user = user

    Users.register(new_user)

    assert_delivered_message %Message{
      to: new_user.phone_number,
      body: "Welcome there!"
    }
  end
end

If you only care that any message was delivered, you can use following assertion:

test "message gets delivered" do
  new_user = user

  Users.register(new_user)

  message = assert_delivered_message()
  # do something with the delivered message...
end

Lastly anonymous function matcher is also provided for more flexible assertions:

test "some delivered message attrs match" do
  new_user = user

  Users.register(new_user)

  assert_delivered_message_matches(fn message ->
    assert message.to == new_user.phone_number
    assert message.body =~ "partial match..."
  end)
end

Refute

There is also a refute_delivered_message/1 macro for testing that a specific message was not delivered.

  test "specific message doesn't get delivered" do
    # Do something...

    # assert that following message wasn't sent out
    message = %Apus.Message(to: 123, body: "message")
    refute_delivered_message(message)
  end

Similarly you can also use refute_delivered_message/0 to ensure no messages were delivered.

  test "no messages delivered" do
    # Do something....

    # assert no messages were sent out
    refute_delivered_message()
  end