analytics/test/plausible/http_client_test.exs

defmodule Plausible.HTTPClientTest do
  use ExUnit.Case, async: false

  alias Plausible.HTTPClient
  alias Plug.Conn

  setup do
    bypass = Bypass.open()
    {:ok, bypass: bypass}
  end

  test "get/2 works", %{bypass: bypass} do
    Bypass.expect_once(bypass, "GET", "/get", fn conn ->
      Conn.resp(conn, 200, "ok")
    end)

    assert {:ok, %Finch.Response{status: 200, body: "ok"}} =
             HTTPClient.get(bypass_url(bypass, path: "/get"))
  end

  test "post/3 works", %{bypass: bypass} do
    Bypass.expect_once(bypass, "POST", "/post", fn conn ->
      Conn.resp(conn, 200, "ok")
    end)

    assert {:ok, %Finch.Response{status: 200, body: "ok"}} =
             HTTPClient.post(bypass_url(bypass, path: "/post"))
  end

  test "post/3 doesn't alter params if binary passed",
       %{
         bypass: bypass
       } do
    body = "raw binary"
    headers = []

    Bypass.expect_once(bypass, "POST", "/post", fn conn ->
      opts = Plug.Parsers.init(parsers: [:urlencoded, {:json, json_decoder: Jason}])

      conn
      |> Plug.Parsers.call(opts)
      |> Conn.resp(200, body)
    end)

    assert {:ok, %Finch.Response{status: 200, body: ^body}} =
             HTTPClient.post(bypass_url(bypass, path: "/post"), headers, body)
  end

  test "post/3 URL-encodes params if request content-type is set to application/x-www-form-urlencoded and a map is supplied",
       %{
         bypass: bypass
       } do
    body = %{hello: :world, alice: :bob}
    headers = [{"Content-Type", "application/x-www-form-urlencoded"}]

    Bypass.expect_once(bypass, "POST", "/post", fn conn ->
      opts = Plug.Parsers.init(parsers: [:urlencoded])
      conn = Plug.Parsers.call(conn, opts)

      assert hd(Conn.get_req_header(conn, "content-type")) == "application/x-www-form-urlencoded"
      assert conn.body_params["hello"] == "world"
      assert conn.body_params["alice"] == "bob"
      Conn.resp(conn, 200, "ok")
    end)

    assert {:ok, %Finch.Response{status: 200, body: "ok"}} =
             HTTPClient.post(bypass_url(bypass, path: "/post"), headers, body)
  end

  test "post/3 JSON-encodes params if request content-type is other than application/x-www-form-urlencoded and a map is supplied",
       %{
         bypass: bypass
       } do
    params = %{hello: :world, alice: :bob}
    headers_no_content_type = [{"foo", "moo"}]
    headers_json = [{"Content-Type", "application/json"}]

    Bypass.expect_once(bypass, "POST", "/any", fn conn ->
      opts = Plug.Parsers.init(parsers: [:urlencoded, {:json, json_decoder: Jason}])
      conn = Plug.Parsers.call(conn, opts)

      assert Conn.get_req_header(conn, "content-type") == ["application/json"]
      assert conn.body_params["hello"] == "world"
      assert conn.body_params["alice"] == "bob"
      Conn.resp(conn, 200, "ok")
    end)

    Bypass.expect_once(bypass, "POST", "/json", fn conn ->
      opts = Plug.Parsers.init(parsers: [{:json, json_decoder: Jason}])
      conn = Plug.Parsers.call(conn, opts)

      assert Conn.get_req_header(conn, "content-type") == ["application/json"]
      assert conn.body_params["hello"] == "world"
      assert conn.body_params["alice"] == "bob"
      Conn.resp(conn, 200, "ok")
    end)

    assert {:ok, %Finch.Response{status: 200, body: "ok"}} =
             HTTPClient.post(bypass_url(bypass, path: "/json"), headers_json, params)

    assert {:ok, %Finch.Response{status: 200, body: "ok"}} =
             HTTPClient.post(bypass_url(bypass, path: "/any"), headers_no_content_type, params)
  end

  @tag :slow
  test "post/4 accepts finch request opts", %{bypass: bypass} do
    Bypass.expect_once(bypass, "POST", "/timeout", fn conn ->
      Process.sleep(500)
      Conn.resp(conn, 200, "ok")
    end)

    assert {:error, %Mint.TransportError{reason: :timeout}} ==
             HTTPClient.post(bypass_url(bypass, path: "/timeout"), [], %{}, receive_timeout: 100)

    Bypass.down(bypass)
  end

  test "non-200 responses are tagged as errors", %{bypass: bypass} do
    Bypass.expect_once(bypass, "GET", "/get", fn conn ->
      Conn.resp(conn, 300, "oops")
    end)

    assert {:error,
            %HTTPClient.Non200Error{
              reason: %Finch.Response{status: 300, body: "oops"}
            }} = HTTPClient.get(bypass_url(bypass, path: "/get"))

    Bypass.expect_once(bypass, "GET", "/get", fn conn ->
      Conn.resp(conn, 400, "oops")
    end)

    assert {:error,
            %HTTPClient.Non200Error{
              reason: %Finch.Response{status: 400, body: "oops"}
            }} = HTTPClient.get(bypass_url(bypass, path: "/get"))
  end

  test "header keys are downcased but values are not", %{bypass: bypass} do
    Bypass.expect_once(bypass, "GET", "/get", fn conn ->
      conn
      |> Conn.put_resp_header("Some-Header", "Header-Value")
      |> Conn.resp(200, "ok")
    end)

    assert {:ok, res} = HTTPClient.get(bypass_url(bypass, path: "/get"))
    assert {"some-header", "Header-Value"} in res.headers
  end

  defp bypass_url(bypass, opts) do
    port = bypass.port
    path = Keyword.get(opts, :path, "/")

    "http://localhost:#{port}#{path}"
  end

  test "decodes json in case content-type is found", %{bypass: bypass} do
    Bypass.expect_once(bypass, "GET", "/json", fn conn ->
      conn
      |> Conn.put_resp_header("content-type", "application/json; something")
      |> Conn.resp(200, """
      {"answer": 42}
      """)
    end)

    assert {:ok, %{body: %{"answer" => 42}}} = HTTPClient.get(bypass_url(bypass, path: "/json"))
  end
end