From 618c918320ba678c4633a26b1fde0d1789664704 Mon Sep 17 00:00:00 2001
From: Gonzalo <456459+grzuy@users.noreply.github.com>
Date: Mon, 13 Jan 2025 16:01:08 -0300
Subject: [PATCH 1/2] fix: logs normalized erlang error when unwrapping
 Plug.Conn.WrapperError

---
 lib/bandit/pipeline.ex          | 10 +++++++++-
 test/bandit/http1/plug_test.exs | 12 +++++++++---
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/lib/bandit/pipeline.ex b/lib/bandit/pipeline.ex
index 8d772595..1365c955 100644
--- a/lib/bandit/pipeline.ex
+++ b/lib/bandit/pipeline.ex
@@ -209,7 +209,15 @@ defmodule Bandit.Pipeline do
         ) :: {:ok, Bandit.HTTPTransport.t()} | {:error, term()}
   defp handle_error(:error, %Plug.Conn.WrapperError{} = error, _, transport, span, opts, metadata) do
     # Unwrap the inner error and handle it
-    handle_error(error.kind, error.reason, error.stack, transport, span, opts, metadata)
+    handle_error(
+      error.kind,
+      Exception.normalize(:error, error.reason, error.stack),
+      error.stack,
+      transport,
+      span,
+      opts,
+      metadata
+    )
   end
 
   defp handle_error(:error, %type{} = error, stacktrace, transport, span, opts, metadata)
diff --git a/test/bandit/http1/plug_test.exs b/test/bandit/http1/plug_test.exs
index d2973ca5..538dd925 100644
--- a/test/bandit/http1/plug_test.exs
+++ b/test/bandit/http1/plug_test.exs
@@ -112,7 +112,7 @@ defmodule HTTP1PlugTest do
       get "/" do
         # Quiet the compiler
         _ = conn
-        raise "boom"
+        1 = 0
       end
     end
 
@@ -134,9 +134,15 @@ defmodule HTTP1PlugTest do
       SimpleHTTP1Client.send(client, "GET", "/hello_world", ["host: banana"])
       assert SimpleHTTP1Client.connection_closed_for_reading?(client)
 
-      assert_receive {:log, %{level: :error, msg: {:string, msg}}}, 500
+      assert_receive {:log, %{level: :error, msg: {:string, msg}, meta: meta}}, 500
       refute msg =~ "(Plug.Conn.WrapperError)"
-      assert msg =~ "** (RuntimeError) boom"
+      assert msg =~ "** (MatchError)"
+
+      assert %{
+               domain: [:elixir, :bandit],
+               crash_reason: {%MatchError{}, [_ | _] = _stacktrace},
+               conn: %Plug.Conn{}
+             } = meta
     end
   end
 

From 7453f5c541c94d1ca83ba9c4d89f66c0a91d4e68 Mon Sep 17 00:00:00 2001
From: Gonzalo <456459+grzuy@users.noreply.github.com>
Date: Tue, 14 Jan 2025 15:06:41 -0300
Subject: [PATCH 2/2] generalize exception normalization

---
 lib/bandit/pipeline.ex          | 12 +++---------
 test/bandit/http1/plug_test.exs |  6 +++---
 2 files changed, 6 insertions(+), 12 deletions(-)

diff --git a/lib/bandit/pipeline.ex b/lib/bandit/pipeline.ex
index 1365c955..51af6a8c 100644
--- a/lib/bandit/pipeline.ex
+++ b/lib/bandit/pipeline.ex
@@ -209,15 +209,7 @@ defmodule Bandit.Pipeline do
         ) :: {:ok, Bandit.HTTPTransport.t()} | {:error, term()}
   defp handle_error(:error, %Plug.Conn.WrapperError{} = error, _, transport, span, opts, metadata) do
     # Unwrap the inner error and handle it
-    handle_error(
-      error.kind,
-      Exception.normalize(:error, error.reason, error.stack),
-      error.stack,
-      transport,
-      span,
-      opts,
-      metadata
-    )
+    handle_error(error.kind, error.reason, error.stack, transport, span, opts, metadata)
   end
 
   defp handle_error(:error, %type{} = error, stacktrace, transport, span, opts, metadata)
@@ -238,6 +230,8 @@ defmodule Bandit.Pipeline do
   end
 
   defp handle_error(kind, reason, stacktrace, transport, span, opts, metadata) do
+    reason = Exception.normalize(kind, reason, stacktrace)
+
     Bandit.Telemetry.span_exception(span, kind, reason, stacktrace)
     status = reason |> Plug.Exception.status() |> Plug.Conn.Status.code()
 
diff --git a/test/bandit/http1/plug_test.exs b/test/bandit/http1/plug_test.exs
index 538dd925..d22173dd 100644
--- a/test/bandit/http1/plug_test.exs
+++ b/test/bandit/http1/plug_test.exs
@@ -46,19 +46,19 @@ defmodule HTTP1PlugTest do
       assert SimpleHTTP1Client.connection_closed_for_reading?(client)
 
       assert_receive {:log, %{level: :error, msg: {:string, msg}, meta: meta}}, 500
-      assert msg =~ "(RuntimeError) boom"
+      assert msg =~ "(ArithmeticError)"
       assert msg =~ "lib/bandit/pipeline.ex:"
 
       assert %{
                domain: [:elixir, :bandit],
-               crash_reason: {%RuntimeError{message: "boom"}, [_ | _] = _stacktrace},
+               crash_reason: {%ArithmeticError{}, [_ | _] = _stacktrace},
                conn: %Plug.Conn{},
                plug: {__MODULE__, []}
              } = meta
     end
 
     def unknown_crasher(_conn) do
-      raise "boom"
+      1 / 0
     end
 
     @tag :capture_log