Add channel to be joined

test/birdy_chat_web/channels/server_channel_test.exs

@@ -0,0 +1,81 @@
+defmodule BirdyChatWeb.ServerChannelTest do
+  use BirdyChatWeb.ChannelCase
+
+  setup do
+    server_id = "test2"
+    token = Phoenix.Token.sign(BirdyChatWeb.Endpoint, "serverAuth", server_id)
+
+    path = Application.app_dir(:birdy_chat, ["priv", "messages", "test-user.txt"])
+    on_exit(fn -> File.rm(path) end)
+
+    {:ok, _, socket} =
+      BirdyChatWeb.ServerSocket
+      |> socket("server_socket", %{server_id: server_id})
+      |> subscribe_and_join(BirdyChatWeb.ServerChannel, "server:#{server_id}", %{token: token})
+
+    %{socket: socket}
+  end
+
+  describe "authorization" do
+    test "requires a signed token to join a channel" do
+      server_id = "test2"
+      token = Phoenix.Token.sign(BirdyChatWeb.Endpoint, "fakeAuth", server_id)
+
+      result =
+        BirdyChatWeb.ServerSocket
+        |> socket("server_socket", %{server_id: server_id})
+        |> subscribe_and_join(BirdyChatWeb.ServerChannel, "server:#{server_id}", %{token: token})
+
+      assert result == {:error, %{reason: "unauthorised"}}
+    end
+
+    test "requires server id in token and in channel to match" do
+      server_id = "test2"
+      token = Phoenix.Token.sign(BirdyChatWeb.Endpoint, "serverAuth", server_id)
+
+      result =
+        BirdyChatWeb.ServerSocket
+        |> socket("server_socket", %{server_id: server_id})
+        |> subscribe_and_join(BirdyChatWeb.ServerChannel, "server:fake", %{token: token})
+
+      assert result == {:error, %{reason: "unauthorised"}}
+    end
+  end
+
+  describe "new_message" do
+    test "receives message from other server and saves it locally", %{socket: socket} do
+      message = %{from: "test2-user", to: "test-user", message: "123"}
+      bin = :erlang.term_to_binary(message)
+      ref = push(socket, "new_message", {:binary, bin})
+      assert_reply ref, :ok, {:binary, ^bin}
+
+      path = Application.app_dir(:birdy_chat, ["priv", "messages", "test-user.txt"])
+      contents = File.read!(path)
+      assert contents == "test2-user: 123\n"
+    end
+
+    test "blows up when sent payload is not safe to decode", %{socket: socket} do
+      # This unsafe binary is taken from erlang docs directly:
+      bin = <<131, 119, 8, "tjenixen">>
+      Process.flag(:trap_exit, true)
+      push(socket, "new_message", {:binary, bin})
+
+      assert_receive {:EXIT, _pid,
+                      {:badarg,
+                       [
+                         {:erlang, :binary_to_term,
+                          [<<131, 119, 8, 116, 106, 101, 110, 105, 120, 101, 110>>, [:safe]],
+                          [error_info: %{module: :erl_erts_errors}]},
+                         {BirdyChatWeb.ServerChannel, :handle_in, 3,
+                          [file: ~c"lib/birdy_chat_web/channels/server_channel.ex", line: 15]},
+                         {Phoenix.Channel.Server, :handle_info, 2,
+                          [file: ~c"lib/phoenix/channel/server.ex", line: 332]},
+                         {:gen_server, :try_handle_info, 3,
+                          [file: ~c"gen_server.erl", line: 2434]},
+                         {:gen_server, :handle_msg, 3, [file: ~c"gen_server.erl", line: 2420]},
+                         {:proc_lib, :init_p_do_apply, 3, [file: ~c"proc_lib.erl", line: 333]}
+                       ]}},
+                     100
+    end
+  end
+end

test/support/channel_case.ex

@@ -0,0 +1,34 @@
+defmodule BirdyChatWeb.ChannelCase do
+  @moduledoc """
+  This module defines the test case to be used by
+  channel tests.
+
+  Such tests rely on `Phoenix.ChannelTest` and also
+  import other functionality to make it easier
+  to build common data structures and query the data layer.
+
+  Finally, if the test case interacts with the database,
+  we enable the SQL sandbox, so changes done to the database
+  are reverted at the end of every test. If you are using
+  PostgreSQL, you can even run database tests asynchronously
+  by setting `use BirdyChatWeb.ChannelCase, async: true`, although
+  this option is not recommended for other databases.
+  """
+
+  use ExUnit.CaseTemplate
+
+  using do
+    quote do
+      # Import conveniences for testing with channels
+      import Phoenix.ChannelTest
+      import BirdyChatWeb.ChannelCase
+
+      # The default endpoint for testing
+      @endpoint BirdyChatWeb.Endpoint
+    end
+  end
+
+  setup _tags do
+    :ok
+  end
+end