1 files changed, 27 insertions, 3 deletions
diff --git a/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb b/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb
index 1c720c5a8e..33edad8bd9 100644
--- a/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb
+++ b/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "action_dispatch/http/request"
 require "action_dispatch/middleware/exception_wrapper"
 require "action_dispatch/routing/inspector"
@@ -10,7 +12,7 @@ module ActionDispatch
   # This middleware is responsible for logging exceptions and
   # showing a debugging page in case the request is local.
   class DebugExceptions
-    RESCUES_TEMPLATE_PATH = File.expand_path("../templates", __FILE__)
+    RESCUES_TEMPLATE_PATH = File.expand_path("templates", __dir__)
 
     class DebugView < ActionView::Base
       def debug_params(params)
@@ -21,7 +23,7 @@ module ActionDispatch
         if clean_params.empty?
           "None"
         else
-          PP.pp(clean_params, "", 200)
+          PP.pp(clean_params, "".dup, 200)
         end
       end
 
@@ -48,10 +50,18 @@ module ActionDispatch
       end
     end
 
-    def initialize(app, routes_app = nil, response_format = :default)
+    cattr_reader :interceptors, instance_accessor: false, default: []
+
+    def self.register_interceptor(object = nil, &block)
+      interceptor = object || block
+      interceptors << interceptor
+    end
+
+    def initialize(app, routes_app = nil, response_format = :default, interceptors = self.class.interceptors)
       @app             = app
       @routes_app      = routes_app
       @response_format = response_format
+      @interceptors    = interceptors
     end
 
     def call(env)
@@ -65,12 +75,26 @@ module ActionDispatch
 
       response
     rescue Exception => exception
+      invoke_interceptors(request, exception)
       raise exception unless request.show_exceptions?
       render_exception(request, exception)
     end
 
     private
 
+      def invoke_interceptors(request, exception)
+        backtrace_cleaner = request.get_header("action_dispatch.backtrace_cleaner")
+        wrapper = ExceptionWrapper.new(backtrace_cleaner, exception)
+
+        @interceptors.each do |interceptor|
+          begin
+            interceptor.call(request, exception)
+          rescue Exception
+            log_error(request, wrapper)
+          end
+        end
+      end
+
       def render_exception(request, exception)
         backtrace_cleaner = request.get_header("action_dispatch.backtrace_cleaner")
         wrapper = ExceptionWrapper.new(backtrace_cleaner, exception)