Log exception rows at Rails' debug_exception_log_level instead of always fatal

lib/logtail-rails/error_event.rb

@@ -18,9 +18,11 @@ class ErrorEvent < Logtail::Integrations::Rack::Middleware
         # We determine this when the app loads to avoid the overhead on a per request basis.
         EXCEPTION_WRAPPER_TAKES_CLEANER = defined?(::ActionDispatch::ExceptionWrapper) &&
           !::ActionDispatch::ExceptionWrapper.instance_methods.include?(:env)
-        # config.action_dispatch.log_rescued_responses (Rails 7.0+), as ActionDispatch::DebugExceptions
-        # reads it. This gem silences its logging and logs the exception here instead.
+        # config.action_dispatch.log_rescued_responses (Rails 7.0+) and
+        # config.action_dispatch.debug_exception_log_level (Rails 7.1+), as ActionDispatch::DebugExceptions
+        # reads them. This gem silences its logging and logs the exception here instead.
         LOG_RESCUED_RESPONSES_KEY = "action_dispatch.log_rescued_responses".freeze
+        DEBUG_EXCEPTION_LOG_LEVEL_KEY = "action_dispatch.debug_exception_log_level".freeze
 
         def call(env)
           begin
@@ -38,7 +40,7 @@ def call(env)
         def log_exception(env, exception)
           return if !log_exception?(env, exception)
 
-          Config.instance.logger.fatal do
+          Config.instance.logger.add(env[DEBUG_EXCEPTION_LOG_LEVEL_KEY] || ::Logger::FATAL) do
             backtrace = extract_backtrace(env, exception)
             Events::Error.new(
               name: exception.class.name,

spec/logtail-rails/error_event_spec.rb

@@ -139,14 +139,45 @@ def method_for_action(action_name)
       expect(response_statuses).to eq([404, 500])
     end
 
-    it "should log the error at fatal even when config.action_dispatch.debug_exception_log_level is :error" do
+    it "should log the error at config.action_dispatch.debug_exception_log_level, :error with load_defaults 7.1 or later" do
       skip("config.action_dispatch.debug_exception_log_level is new in Rails 7.1") unless ::Rails.application.env_config.key?("action_dispatch.debug_exception_log_level")
 
       dispatch_rendering_exceptions("/runtime_error", "action_dispatch.debug_exception_log_level" => ::Logger::ERROR)
 
+      expect(error_rows.map { |row| [row["level"], row["message"]] }).to eq([["error", "RuntimeError (Boom!)"]])
+      expect(response_statuses).to eq([500])
+    end
+
+    it "should log every error, rescued responses too, at warn when config.action_dispatch.debug_exception_log_level is :warn" do
+      skip("config.action_dispatch.debug_exception_log_level is new in Rails 7.1") unless ::Rails.application.env_config.key?("action_dispatch.debug_exception_log_level")
+
+      dispatch_rendering_exceptions("/runtime_error", "action_dispatch.debug_exception_log_level" => ::Logger::WARN)
+      dispatch_rendering_exceptions("/record_not_found", "action_dispatch.debug_exception_log_level" => ::Logger::WARN)
+
+      expect(error_rows.map { |row| [row["level"], row["message"]] }).to eq([["warn", "RuntimeError (Boom!)"], ["warn", "ActiveRecord::RecordNotFound (Couldn't find User)"]])
+      expect(response_statuses).to eq([500, 404])
+    end
+
+    it "should log the error at fatal, Rails' default, when the app doesn't set config.action_dispatch.debug_exception_log_level" do
+      skip("config.action_dispatch.debug_exception_log_level is new in Rails 7.1") unless ::Rails.application.env_config.key?("action_dispatch.debug_exception_log_level")
+
+      # The spec app neither sets it nor loads the 7.1 defaults, so it has the railtie's :fatal
+      expect(::Rails.application.env_config["action_dispatch.debug_exception_log_level"]).to eq(::Logger::FATAL)
+
+      dispatch_rendering_exceptions("/runtime_error")
+
       expect(error_rows.map { |row| [row["level"], row["message"]] }).to eq([["fatal", "RuntimeError (Boom!)"]])
     end
 
+    it "should log every error at fatal on Rails versions without config.action_dispatch.debug_exception_log_level" do
+      skip("config.action_dispatch.debug_exception_log_level exists since Rails 7.1") if ::Rails.application.env_config.key?("action_dispatch.debug_exception_log_level")
+
+      dispatch_rendering_exceptions("/runtime_error")
+      dispatch_rendering_exceptions("/record_not_found")
+
+      expect(error_rows.map { |row| [row["level"], row["message"]] }).to eq([["fatal", "RuntimeError (Boom!)"], ["fatal", "ActiveRecord::RecordNotFound (Couldn't find User)"]])
+    end
+
     # Renders exceptions as error pages like a production app, instead of raising them
     def dispatch_rendering_exceptions(path, env_config = {})
       show_exceptions = ::Rails.gem_version >= Gem::Version.new("7.1") ? :all : true