test: better tests

lib/tower_rollbar/rollbar/client.ex

@@ -1,12 +1,11 @@
 defmodule TowerRollbar.Rollbar.Client do
-  @base_url "https://api.rollbar.com/api/1"
   @access_token_header ~c"X-Rollbar-Access-Token"
 
   def post(path, payload) when is_map(payload) do
     :httpc.request(
       :post,
       {
-        ~c"#{@base_url}#{path}",
+        ~c"#{base_url()}#{path}",
         [{@access_token_header, access_token()}],
         ~c"application/json",
         Jason.encode!(payload)
@@ -53,4 +52,8 @@ defmodule TowerRollbar.Rollbar.Client do
   defp access_token do
     Application.fetch_env!(:tower_rollbar, :access_token)
   end
+
+  defp base_url do
+    Application.get_env(:tower_rollbar, :rollbar_base_url, "https://api.rollbar.com/api/1")
+  end
 end

mix.exs

@@ -37,7 +37,11 @@ defmodule TowerRollbar.MixProject do
       {:plug, "~> 1.16"},
 
       # Only needed for Erlang < 25
-      {:castore, "~> 1.0", optional: true}
+      {:castore, "~> 1.0", optional: true},
+
+
+      # Test
+      {:bypass, "~> 2.1"}
     ]
   end
 

mix.lock

@@ -1,9 +1,15 @@
 %{
+  "bypass": {:hex, :bypass, "2.1.0", "909782781bf8e20ee86a9cabde36b259d44af8b9f38756173e8f5e2e1fabb9b1", [:mix], [{:plug, "~> 1.7", [hex: :plug, repo: "hexpm", optional: false]}, {:plug_cowboy, "~> 2.0", [hex: :plug_cowboy, repo: "hexpm", optional: false]}, {:ranch, "~> 1.3", [hex: :ranch, repo: "hexpm", optional: false]}], "hexpm", "d9b5df8fa5b7a6efa08384e9bbecfe4ce61c77d28a4282f79e02f1ef78d96b80"},
   "castore": {:hex, :castore, "1.0.8", "dedcf20ea746694647f883590b82d9e96014057aff1d44d03ec90f36a5c0dc6e", [:mix], [], "hexpm", "0b2b66d2ee742cb1d9cb8c8be3b43c3a70ee8651f37b75a8b982e036752983f1"},
+  "cowboy": {:hex, :cowboy, "2.12.0", "f276d521a1ff88b2b9b4c54d0e753da6c66dd7be6c9fca3d9418b561828a3731", [:make, :rebar3], [{:cowlib, "2.13.0", [hex: :cowlib, repo: "hexpm", optional: false]}, {:ranch, "1.8.0", [hex: :ranch, repo: "hexpm", optional: false]}], "hexpm", "8a7abe6d183372ceb21caa2709bec928ab2b72e18a3911aa1771639bef82651e"},
+  "cowboy_telemetry": {:hex, :cowboy_telemetry, "0.4.0", "f239f68b588efa7707abce16a84d0d2acf3a0f50571f8bb7f56a15865aae820c", [:rebar3], [{:cowboy, "~> 2.7", [hex: :cowboy, repo: "hexpm", optional: false]}, {:telemetry, "~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "7d98bac1ee4565d31b62d59f8823dfd8356a169e7fcbb83831b8a5397404c9de"},
+  "cowlib": {:hex, :cowlib, "2.13.0", "db8f7505d8332d98ef50a3ef34b34c1afddec7506e4ee4dd4a3a266285d282ca", [:make, :rebar3], [], "hexpm", "e1e1284dc3fc030a64b1ad0d8382ae7e99da46c3246b815318a4b848873800a4"},
   "jason": {:hex, :jason, "1.4.3", "d3f984eeb96fe53b85d20e0b049f03e57d075b5acda3ac8d465c969a2536c17b", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "9a90e868927f7c777689baa16d86f4d0e086d968db5c05d917ccff6d443e58a3"},
   "mime": {:hex, :mime, "2.0.5", "dc34c8efd439abe6ae0343edbb8556f4d63f178594894720607772a041b04b02", [:mix], [], "hexpm", "da0d64a365c45bc9935cc5c8a7fc5e49a0e0f9932a761c55d6c52b142780a05c"},
   "plug": {:hex, :plug, "1.16.1", "40c74619c12f82736d2214557dedec2e9762029b2438d6d175c5074c933edc9d", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:plug_crypto, "~> 1.1.1 or ~> 1.2 or ~> 2.0", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4.3 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "a13ff6b9006b03d7e33874945b2755253841b238c34071ed85b0e86057f8cddc"},
+  "plug_cowboy": {:hex, :plug_cowboy, "2.7.1", "87677ffe3b765bc96a89be7960f81703223fe2e21efa42c125fcd0127dd9d6b2", [:mix], [{:cowboy, "~> 2.7", [hex: :cowboy, repo: "hexpm", optional: false]}, {:cowboy_telemetry, "~> 0.3", [hex: :cowboy_telemetry, repo: "hexpm", optional: false]}, {:plug, "~> 1.14", [hex: :plug, repo: "hexpm", optional: false]}], "hexpm", "02dbd5f9ab571b864ae39418db7811618506256f6d13b4a45037e5fe78dc5de3"},
   "plug_crypto": {:hex, :plug_crypto, "2.1.0", "f44309c2b06d249c27c8d3f65cfe08158ade08418cf540fd4f72d4d6863abb7b", [:mix], [], "hexpm", "131216a4b030b8f8ce0f26038bc4421ae60e4bb95c5cf5395e1421437824c4fa"},
+  "ranch": {:hex, :ranch, "1.8.0", "8c7a100a139fd57f17327b6413e4167ac559fbc04ca7448e9be9057311597a1d", [:make, :rebar3], [], "hexpm", "49fbcfd3682fab1f5d109351b61257676da1a2fdbe295904176d5e521a2ddfe5"},
   "telemetry": {:hex, :telemetry, "1.2.1", "68fdfe8d8f05a8428483a97d7aab2f268aaff24b49e0f599faa091f1d4e7f61c", [:rebar3], [], "hexpm", "dad9ce9d8effc621708f99eac538ef1cbe05d6a874dd741de2e689c47feafed5"},
   "tower": {:git, "https://github.com/mimiquate/tower.git", "20883244a6ac4639c70dc1a8874928c52cd5ea4c", []},
   "uniq": {:hex, :uniq, "0.6.1", "369660ecbc19051be526df3aa85dc393af5f61f45209bce2fa6d7adb051ae03c", [:mix], [{:ecto, "~> 3.0", [hex: :ecto, repo: "hexpm", optional: true]}], "hexpm", "6426c34d677054b3056947125b22e0daafd10367b85f349e24ac60f44effb916"},

test/tower_rollbar_test.exs

@@ -1,4 +1,70 @@
 defmodule TowerRollbarTest do
   use ExUnit.Case
   doctest TowerRollbar
+
+  setup do
+    bypass = Bypass.open()
+
+    Application.put_env(:tower, :reporters, [TowerRollbar.Reporter])
+    Application.put_env(:tower_rollbar, :rollbar_base_url, "http://localhost:#{bypass.port}/")
+    Application.put_env(:tower_rollbar, :environment, :test)
+    Application.put_env(:tower_rollbar, :access_token, "fake-token")
+    Application.put_env(:tower_rollbar, :enabled, true)
+
+    Tower.attach()
+
+    on_exit(fn ->
+      Tower.detach()
+    end)
+
+    {:ok, bypass: bypass}
+  end
+
+  @tag capture_log: true
+  test "reports arithmetic error", %{bypass: bypass} do
+    # ref message synchronization trick copied from
+    # https://github.com/PSPDFKit-labs/bypass/issues/112
+    parent = self()
+    ref = make_ref()
+
+    Bypass.expect_once(bypass, "POST", "/item", fn conn ->
+      {:ok, body, conn} = Plug.Conn.read_body(conn)
+
+      assert(
+        %{
+          "data" => %{
+            "environment" => "test",
+            "body" => %{
+              "trace" => %{
+                "exception" => %{
+                  "class" => "ArithmeticError",
+                  "message" => "bad argument in arithmetic expression"
+                }
+              }
+            }
+          }
+        } = Jason.decode!(body)
+      )
+
+      send(parent, {ref, :sent})
+
+      conn
+      |> Plug.Conn.put_resp_content_type("application/json")
+      |> Plug.Conn.resp(200, Jason.encode!(%{"ok" => true}))
+    end)
+
+    in_unlinked_process(fn ->
+      1 / 0
+    end)
+
+    assert_receive({^ref, :sent}, 500)
+  end
+
+  defp in_unlinked_process(fun) when is_function(fun, 0) do
+    {:ok, pid} = Task.Supervisor.start_link()
+
+    pid
+    |> Task.Supervisor.async_nolink(fun)
+    |> Task.yield()
+  end
 end