adding functionality to create user

lib/zendex/user.ex

@@ -0,0 +1,21 @@
+defmodule Zendex.User do
+  @moduledoc """
+  Interact with Zendesk user.
+  """
+
+  alias Zendex.CommonHelpers
+
+  @url "/api/v2/users.json"
+  @http_client Application.get_env(:zendex, :http_client)
+
+  @spec create(Zendex.Connection.t, map) :: map
+  def create(connection, user) do
+    connection.base_url
+    |> Kernel.<>(@url)
+    |> @http_client.post!(Poison.encode!(user),
+                          CommonHelpers.get_headers(connection.authentication,
+                                                    %{content_type: :json}))
+    |> CommonHelpers.decode_response
+  end
+
+end

test/zendex/user_test.exs

@@ -0,0 +1,14 @@
+defmodule Zendex.UserTest do
+  use ExUnit.Case, async: true
+
+  setup do
+    [conn: Zendex.Connection.set_up("http://test.zendesk.com", "User1", "pass")]
+  end
+
+  test "creating a user", context do
+    expected = %{"user" => %{"id" => 1234, "name" => "Roger", "email" => "roger@dodger.com"}}
+    actual = Zendex.User.create(context[:conn], %{user: %{name: "Roger", email: "roger@dodger.com"}})
+
+    assert expected == actual
+  end
+end