Rework stop event and re-add original event

josephfoster051 · Oct 16, 2019 · 4b961cc · 4b961cc
1 parent c1e01c1
commit 4b961cc
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Showing 2 changed files with 42 additions and 37 deletions.
diff --git a/lib/tesla/middleware/telemetry.ex b/lib/tesla/middleware/telemetry.ex
@@ -45,56 +45,61 @@ if Code.ensure_loaded?(:telemetry) do
     """
 
     @doc false
-    def call(req_env, next, opts) do
+    def call(env, next, opts) do
       prefix = Keyword.get(opts, :event_prefix, [])
       start_time = System.monotonic_time()
 
-      try do
-        emit_start(req_env, start_time, prefix)
+      emit_start(env, start_time, prefix)
 
-        Tesla.run(req_env, next)
-        |> emit_result(start_time, prefix, req_env)
-      rescue
-        e ->
-          stacktrace = System.stacktrace()
-          metadata = %{env: req_env, exception: e, stacktrace: stacktrace}
+      result =
+        try do
+          Tesla.run(env, next)
+        rescue
+          e ->
+            stacktrace = System.stacktrace()
+            metadata = %{env: env, exception: e, stacktrace: stacktrace}
 
-          :telemetry.execute(
-            prefix ++ [:tesla, :request, :exception],
-            %{duration: System.monotonic_time() - start_time},
-            metadata
-          )
+            :telemetry.execute(
+              prefix ++ [:tesla, :request, :exception],
+              %{duration: System.monotonic_time() - start_time},
+              metadata
+            )
 
-          reraise e, stacktrace
-      end
+            reraise e, stacktrace
+        end
+
+      emit_stop(result, start_time, prefix, env)
+
+      result
     end
 
-    defp emit_start(req_env, start_time, prefix) do
+    defp emit_start(env, start_time, prefix) do
       :telemetry.execute(prefix ++ [:tesla, :request, :start], %{time: start_time}, %{
-        env: req_env
+        env: env
       })
     end
 
-    defp emit_result(result, start_time, prefix, req_env) do
-      try do
-        result
-      after
-        case result do
-          {:ok, env} ->
-            :telemetry.execute(
-              prefix ++ [:tesla, :request, :stop],
-              %{duration: System.monotonic_time() - start_time},
-              %{env: env}
-            )
+    defp emit_stop(result, start_time, prefix, req_env) do
+      duration = System.monotonic_time() - start_time
 
-          {:error, error} ->
-            :telemetry.execute(
-              prefix ++ [:tesla, :request, :error],
-              %{duration: System.monotonic_time() - start_time},
-              %{env: req_env, reason: error}
-            )
-        end
+      case result do
+        {:ok, env} ->
+          :telemetry.execute(
+            prefix ++ [:tesla, :request, :stop],
+            %{duration: duration},
+            %{env: env}
+          )
+
+        {:error, error} ->
+          :telemetry.execute(
+            prefix ++ [:tesla, :request, :error],
+            %{duration: duration},
+            %{env: req_env, reason: error}
+          )
       end
+
+      # retained for backwards compatibility - remove in 2.0
+      :telemetry.execute([:tesla, :request], %{request_time: duration}, %{result: result})
     end
   end
 end
diff --git a/mix.exs b/mix.exs
@@ -71,7 +71,7 @@ defmodule Tesla.Mixfile do
 
       # other
       {:fuse, "~> 2.4", optional: true},
-      {:telemetry, "~> 0.3", optional: true},
+      {:telemetry, "~> 0.4", optional: true},
 
       # testing & docs
       {:excoveralls, "~> 0.8", only: :test},