Preparatory work

test/birdy_chat_web/api/messages_test.exs

@@ -0,0 +1,40 @@
+defmodule BirdyChatWeb.Api.MessagesTest do
+  use BirdyChatWeb.ConnCase
+
+  setup %{conn: conn} do
+    url = ~p"/api/messages"
+
+    conn =
+      conn
+      |> put_req_header("content-type", "application/json")
+
+    %{conn: conn, url: url}
+  end
+
+  describe "POST /api/messages" do
+    test "returns errors for invalid message", %{conn: conn, url: url} do
+      payload = Jason.encode!(%{})
+      conn = post(conn, url, payload)
+      assert result = json_response(conn, :unprocessable_entity)
+
+      expected_result = %{
+        "errors" => %{
+          "from" => ["can't be blank"],
+          "message" => ["can't be blank"],
+          "to" => ["can't be blank"]
+        }
+      }
+
+      assert result == expected_result
+    end
+
+    test "returns message and ok when successful", %{conn: conn, url: url} do
+      message = %{"from" => "2-user", "to" => "1-user", "message" => "123"}
+      payload = Jason.encode!(message)
+      conn = post(conn, url, payload)
+      assert result = json_response(conn, :created)
+
+      assert result == message
+    end
+  end
+end