add MessageRecovery module (mercadona#56)

lib/postoffice/rescuer/client.ex

@@ -10,7 +10,7 @@ defmodule Postoffice.Rescuer.Client do
         Logger.info("Succesfully listed pending messages from #{host}")
         {:ok, Poison.decode!(body)}
 
-      {:ok, %HTTPoison.Response{status_code: status_code, body: body}} ->
+      {:ok, %HTTPoison.Response{status_code: status_code}} ->
         Logger.info(
           "Non successful response list pending messages from #{host} with status code: #{
             status_code
@@ -31,7 +31,7 @@ defmodule Postoffice.Rescuer.Client do
       when status_code in 200..299 ->
         Logger.info("Successfully deleted message #{message_id} from #{host}")
         {:ok, :deleted}
-      {:ok, %HTTPoison.Response{status_code: status_code, body: body}} ->
+      {:ok, %HTTPoison.Response{status_code: status_code}} ->
         Logger.info(
           "Non successful response deleting message from #{host} with status code: #{
             status_code

lib/postoffice/rescuer/message_recovery.ex

@@ -0,0 +1,29 @@
+defmodule Postoffice.Rescuer.MessageRecovery do
+  alias Postoffice.Rescuer.Client
+
+  require Logger
+
+  def run(host) do
+    Logger.info("Started MessageRecovery for host #{host}")
+    case Client.list(host) do
+      {:ok, []} ->
+        Logger.info("Undelivered messages not found on #{host}")
+      {:ok, messages} ->
+        messages
+        |> Enum.map(fn message -> handle_message(message, host) end)
+      {:error, []} ->
+        Logger.info("Error on #{host} listing undelivering messages")
+    end
+  end
+
+  defp handle_message(message, host) do
+    {id, message_params} = Map.pop(message, "id")
+    case Postoffice.receive_message(message_params) do
+      {:ok, created_message} ->
+        Logger.info("Successfully recovered message for topic #{created_message["topic"]} with public_id #{created_message["public_id"]}")
+        Client.delete(host, id)
+      {:relationship_does_not_exists, _errors} ->
+        Logger.info("Trying to receive message for non existing topic #{message["topic"]}")
+    end
+  end
+end

test/postoffice/rescuer/message_recovery_test.exs

@@ -0,0 +1,73 @@
+defmodule Postoffice.Rescuer.MessageRecoveryTest do
+  use ExUnit.Case
+
+  import Mox
+
+  alias Postoffice.Fixtures
+  alias Postoffice.Messaging
+  alias Postoffice.Rescuer.Adapters.HttpMock
+  alias Postoffice.Rescuer.MessageRecovery
+
+  @origin_host "http://fake_origin.host"
+  @first_message_id 1
+  @second_message_id 2
+  @one_message_response "[{\"id\": 1, \"topic\": \"test\", \"payload\": {\"products\": [{\"code\": \"1234\"}, {\"code\": 2345}], \"reference\": 1234}, \"attributes\": {}}]"
+  @two_messages_response "[{\"id\": 1, \"topic\": \"test\", \"payload\": {\"products\": [{\"code\": \"1234\"}, {\"code\": 2345}], \"reference\": 1234}, \"attributes\": {}}, {\"id\": 2, \"topic\": \"test\", \"payload\": {\"products\": [{\"code\": \"1234\"}, {\"code\": 2345}], \"reference\": 1234}, \"attributes\": {}}]"
+  @wrong_topic_message "[{\"id\": 1, \"topic\": \"test2\", \"payload\": {\"products\": [{\"code\": \"1234\"}, {\"code\": 2345}], \"reference\": 1234}, \"attributes\": {}}]"
+
+  setup [:set_mox_from_context, :verify_on_exit!]
+
+  setup do
+    :ok = Ecto.Adapters.SQL.Sandbox.checkout(Postoffice.Repo)
+  end
+
+  describe "recover messages" do
+    test "no message created if no undelivered message found" do
+      expect(HttpMock, :list, fn @origin_host ->
+        {:ok, %HTTPoison.Response{status_code: 200, body: "[]"}}
+      end)
+
+      MessageRecovery.run(@origin_host)
+      assert Messaging.list_messages() == []
+    end
+
+    test "message created if one undelivered message found" do
+      expect(HttpMock, :list, fn @origin_host ->
+        {:ok, %HTTPoison.Response{status_code: 200, body: @one_message_response}}
+      end)
+
+      expect(HttpMock, :delete, fn @origin_host, @first_message_id ->
+        {:ok, %HTTPoison.Response{status_code: 204}}
+      end)
+
+      Fixtures.create_topic()
+      MessageRecovery.run(@origin_host)
+      assert Kernel.length(Messaging.list_messages()) == 1
+    end
+
+    test "more than one message is created if multiple undelivered messages found" do
+      expect(HttpMock, :list, fn @origin_host ->
+        {:ok, %HTTPoison.Response{status_code: 200, body: @two_messages_response}}
+      end)
+      expect(HttpMock, :delete, fn @origin_host, @first_message_id ->
+        {:ok, %HTTPoison.Response{status_code: 204}}
+      end)
+      expect(HttpMock, :delete, fn @origin_host, @second_message_id ->
+        {:ok, %HTTPoison.Response{status_code: 204}}
+      end)
+
+      Fixtures.create_topic()
+      MessageRecovery.run(@origin_host)
+      assert Kernel.length(Messaging.list_messages()) == 2
+    end
+
+    test "no message created if something fails" do
+      expect(HttpMock, :list, fn @origin_host ->
+        {:ok, %HTTPoison.Response{status_code: 200, body: @wrong_topic_message}}
+      end)
+
+      MessageRecovery.run(@origin_host)
+      assert Kernel.length(Messaging.list_messages()) == 0
+    end
+  end
+end