Appeasing the dialyzer

* [Refactored] Bonny.Telemetry.emit/N to remove unused signatures and
correct per dialyzer errors

lib/bonny/application.ex

@@ -4,8 +4,6 @@ defmodule Bonny.Application do
   use Application
 
   def start(_type, _args) do
-    Bonny.Telemetry.attach()
-
     children =
       Bonny.Config.controllers()
       |> Enum.map(fn controller ->

lib/bonny/telemetry.ex

@@ -2,6 +2,7 @@ defmodule Bonny.Telemetry do
   @moduledoc """
   List of telemetry events.
   """
+
   @spec events() :: list(list(atom))
   def events() do
     [
@@ -12,27 +13,17 @@ defmodule Bonny.Telemetry do
   end
 
   @doc """
-  Emits telemetry.
+  Wrapper around `:telemetry.execute/3`.
 
-  **Note:** This method switches the order of `measurements` and `metadata`
+  Prepends `:bonnny` to all atom lists.
   """
-  @spec emit(atom) :: no_return
-  @spec emit(atom, fun) :: no_return
-  @spec emit(atom, map) :: no_return
-  @spec emit(atom, map, map) :: no_return
-  @spec emit(atom, map, fun) :: no_return
-  @spec emit(list(atom), map, fun) :: no_return
-  def emit(name), do: emit(name, %{}, %{})
-  def emit(name, metadata = %{}), do: emit(name, %{}, metadata)
-  def emit(name, func) when is_function(func), do: emit(name, %{}, func)
-
-  def emit(name, metadata = %{}, func) when is_function(func),
-    do: emit(name, metadata, %{duration: measure(func)})
+  @spec emit(list(atom)) :: :ok
+  @spec emit(list(atom), map) :: :ok
+  @spec emit(list(atom), map, map) :: :ok
+  def emit(names), do: emit(names, %{}, %{})
+  def emit(names, measurements = %{}), do: emit(names, measurements, %{})
 
-  def emit(name, metadata = %{}, measurements = %{}) when is_atom(name),
-    do: emit([name], measurements, metadata)
-
-  def emit(names, metadata = %{}, measurements = %{}) when is_list(names),
+  def emit(names, measurements = %{}, metadata = %{}),
     do: :telemetry.execute([:bonny | names], measurements, metadata)
 
   @doc """
@@ -53,20 +44,12 @@ defmodule Bonny.Telemetry do
 
     {seconds, retval}
   end
-
-  @spec attach() :: no_return
-  @doc false
-  def attach() do
-    :telemetry.attach_many(
-      "debug-logger",
-      events(),
-      &Bonny.Telemetry.DebugLogger.handle_event/4,
-      nil
-    )
-  end
 end
 
 defmodule Bonny.Telemetry.DebugLogger do
+  @moduledoc """
+  A telemetry logger for debugging.
+  """
   require Logger
 
   def handle_event(event, measurements, metadata, _config) do
@@ -75,4 +58,15 @@ defmodule Bonny.Telemetry.DebugLogger do
       "[#{event_name}] #{inspect(measurements)} #{inspect(metadata)}"
     end)
   end
+
+  @doc false
+  @spec attach() :: no_return
+  def attach() do
+    :telemetry.attach_many(
+      "debug-logger",
+      Bonny.Telemetry.events(),
+      &Bonny.Telemetry.DebugLogger.handle_event/4,
+      nil
+    )
+  end
 end

lib/bonny/watcher.ex

@@ -14,12 +14,8 @@ defmodule Bonny.Watcher do
   @impl GenServer
   def init(controller) do
     state = Impl.new(controller)
-    schedule_watcher()
-    {:ok, state}
-  end
-
-  defp schedule_watcher() do
     Process.send_after(self(), :watch, 5000)
+    {:ok, state}
   end
 
   def handle_info(:watch, state) do

lib/bonny/watcher/impl.ex

@@ -16,9 +16,13 @@ defmodule Bonny.Watcher.Impl do
 
   defstruct [:spec, :controller, :resource_version]
 
+  @doc """
+  Initialize a `Bonny.Watcher` state
+  """
+  @spec new(module()) :: Impl.t()
   def new(controller) do
     spec = apply(controller, :crd_spec, [])
-    Bonny.Telemetry.emit([:watcher, :initialized], telemetry_metadata(spec))
+    Bonny.Telemetry.emit([:watcher, :initialized], %{}, telemetry_metadata(spec))
 
     %__MODULE__{
       controller: controller,
@@ -32,9 +36,9 @@ defmodule Bonny.Watcher.Impl do
 
   Streams HTTPoison response to `Bonny.Watcher`
   """
-  @spec watch_for_changes(Impl.t(), pid()) :: nil
+  @spec watch_for_changes(Impl.t(), pid()) :: no_return
   def watch_for_changes(state = %Impl{}, watcher) do
-    Bonny.Telemetry.emit([:watcher, :started], telemetry_metadata(state.spec))
+    Bonny.Telemetry.emit([:watcher, :started], %{}, telemetry_metadata(state.spec))
 
     operation = list_operation(state)
     rv = get_resource_version(state)
@@ -97,7 +101,7 @@ defmodule Bonny.Watcher.Impl do
   def dispatch(%{"type" => "DELETED", "object" => object}, controller),
     do: do_dispatch(controller, :delete, object)
 
-  @spec do_dispatch(atom, atom, map) :: nil
+  @spec do_dispatch(atom, atom, map) :: no_return
   defp do_dispatch(controller, event, object) do
     Task.start(fn ->
       {time, result} = Bonny.Telemetry.measure(fn -> apply(controller, event, [object]) end)
@@ -118,7 +122,7 @@ defmodule Bonny.Watcher.Impl do
       measurements = %{duration: time}
       metadata = telemetry_metadata(controller.crd_spec, %{event: event, success: was_successful})
 
-      Bonny.Telemetry.emit([:watcher, :dispatched], metadata, measurements)
+      Bonny.Telemetry.emit([:watcher, :dispatched], measurements, metadata)
     end)
   end
 
@@ -157,7 +161,7 @@ defmodule Bonny.Watcher.Impl do
 
   @doc false
   @spec telemetry_metadata(Bonny.CRD.t(), map | nil) :: map
-  def telemetry_metadata(spec = %Bonny.CRD{}, extra \\ %{}) do
+  defp telemetry_metadata(spec = %Bonny.CRD{}, extra \\ %{}) do
     base = %{
       api_version: Bonny.CRD.api_version(spec),
       kind: Bonny.CRD.kind(spec)

test/support/k8s_mock_client.ex

@@ -1,4 +1,8 @@
 defmodule Bonny.K8sMockClient do
+  @moduledoc """
+  Mock `K8s.Client`
+  """
+
   def list(api_version, kind, path_params) do
     K8s.Operation.build(:list, api_version, kind, path_params)
   end

test/test_helper.exs

@@ -1 +1,2 @@
+Bonny.Telemetry.DebugLogger.attach()
 ExUnit.start()