Merge pull request #8 from Logflare/feat/ex-on-error-callback

feat: add :on_error callback

logflare-ex/lib/logflare_ex.ex

@@ -53,8 +53,18 @@ defmodule LogflareEx do
     body = Bertex.encode(%{"batch" => batch, "source" => client.source_token})
 
     case Tesla.post(client.tesla_client, "/api/logs", body) do
-      %Tesla.Env{status: 201, body: body} -> {:ok, Jason.decode!(body)}
-      %Tesla.Env{} = result -> {:error, result}
+      %Tesla.Env{status: 201, body: body} ->
+        {:ok, Jason.decode!(body)}
+
+      %Tesla.Env{} = result ->
+        # on_error callback
+        case Map.get(client, :on_error) do
+          {m, f, 1} -> apply(m, f, [result])
+          cb when is_function(cb) -> cb.(result)
+          _ -> :noop
+        end
+
+        {:error, result}
     end
   end
 end

logflare-ex/lib/logflare_ex/client.ex

@@ -10,6 +10,7 @@ defmodule LogflareEx.Client do
     field(:api_key, String.t(), enforce: true)
     field(:api_url, String.t(), default: "https://api.logflare.app")
     field(:source_token, String.t())
+    field(:on_error, list() | mfa(), default: nil)
   end
 
   @typep opts :: [api_key: String.t(), api_url: String.t(), tesla_client: Tesla.Client.t()]
@@ -21,7 +22,8 @@ defmodule LogflareEx.Client do
         api_key: get_config_value(:api_key),
         adapter: get_config_value(:adapter) || @default_tesla_adapter,
         source_token: get_config_value(:source_token),
-        tesla_client: nil
+        tesla_client: nil,
+        on_error: get_config_value(:on_error)
       })
 
     tesla_client =
@@ -53,7 +55,7 @@ defmodule LogflareEx.Client do
     Tesla.client(middlewares, adapter)
   end
 
-  defp get_config_value(key) do
+  def get_config_value(key) do
     Application.get_env(:logflare_ex, key)
   end
 end

logflare-ex/mix.exs

@@ -6,7 +6,7 @@ defmodule LogflareEx.MixProject do
   def project do
     [
       app: :logflare_ex,
-      version: "0.1.0#{@version_suffix}",
+      version: "0.1.1#{@version_suffix}",
       build_path: "./_build",
       config_path: "./config/config.exs",
       deps_path: "./deps",
@@ -19,10 +19,15 @@ defmodule LogflareEx.MixProject do
         "test.format": :test,
         "test.compile": :test
       ],
-      package: package()
+      package: package(),
+      elixirc_paths: elixirc_paths(Mix.env())
     ]
   end
 
+  # Specifies which paths to compile per environment.
+  defp elixirc_paths(:test), do: ["lib", "test/support"]
+  defp elixirc_paths(_), do: ["lib"]
+
   # Run "mix help compile.app" to learn about applications.
   def application do
     [

logflare-ex/test/logflare_ex_test.exs

@@ -38,6 +38,26 @@ defmodule LogflareExTest do
              LogflareEx.client(api_key: "123") |> LogflareEx.send_events([%{some: "event"}])
   end
 
+  describe "on_error" do
+    test "triggers on_error mfa if non-201 status is encountered" do
+      Tesla
+      |> expect(:post, 2, fn _client, _path, _body ->
+        %Tesla.Env{status: 500, body: "some server error"}
+      end)
+
+      LogflareEx.TestUtils
+      |> expect(:stub_function, 2, fn %{status: 500} -> :ok end)
+
+      for cb <- [
+            {LogflareEx.TestUtils, :stub_function, 1},
+            &LogflareEx.TestUtils.stub_function/1
+          ] do
+        client = LogflareEx.client(api_key: "123", source_token: "123", on_error: cb)
+        assert {:error, %Tesla.Env{}} = LogflareEx.send_events(client, [%{some: "event"}])
+      end
+    end
+  end
+
   @tag :benchmark
   # Bertex is way faster
   test "benchmark Jason vs Bertex" do

logflare-ex/test/support/test_utils.ex

@@ -0,0 +1,5 @@
+defmodule LogflareEx.TestUtils do
+  @moduledoc false
+
+  def stub_function(_env), do: nil
+end

logflare-ex/test/test_helper.exs

@@ -1,2 +1,3 @@
 Mimic.copy(Tesla)
+Mimic.copy(LogflareEx.TestUtils)
 ExUnit.start(exclude: [:benchmark])