socketry · ioquatix · Aug 20, 2025 · Aug 19, 2025 · Aug 19, 2025 · Aug 19, 2025
diff --git a/examples/recorder/config.ru b/examples/recorder/config.ru
@@ -4,15 +4,15 @@
 # Simple Rack application demonstrating async-http-capture recording
 # This application provides several endpoints that generate different types of responses
 
-require 'json'
-require 'time'
+require "json"
+require "time"
 
 # Simple hello world application with multiple endpoints
 app = lambda do |env|
 	request = Rack::Request.new(env)
 
 	case request.path_info
-	when '/'
+	when "/"
 		# Simple homepage
 		body = <<~HTML
 			<html>
@@ -39,25 +39,25 @@ app = lambda do |env|
 			</html>
 		HTML
 
-		[200, {'Content-Type' => 'text/html'}, [body]]
+		[200, {"Content-Type" => "text/html"}, [body]]
 
-	when '/hello'
+	when "/hello"
 		# Simple text response
-		[200, {'Content-Type' => 'text/plain'}, ["Hello, World! #{Time.now}"]]
+		[200, {"Content-Type" => "text/plain"}, ["Hello, World! #{Time.now}"]]
 
-	when '/json'
+	when "/json"
 		# JSON response
 		data = {
 			message: "Hello from JSON API",
 			timestamp: Time.now.iso8601,
 			random: rand(1000)
 		}
-		[200, {'Content-Type' => 'application/json'}, [JSON.generate(data)]]
+		[200, {"Content-Type" => "application/json"}, [JSON.generate(data)]]
 
-	when '/headers'
+	when "/headers"
 		# Show request headers
-		headers_info = env.select { |k, _| k.start_with?('HTTP_') }
-			.transform_keys { |k| k.sub('HTTP_', '').split('_').map(&:capitalize).join('-') }
+		headers_info = env.select {|k, _| k.start_with?("HTTP_")}
+			.transform_keys {|k| k.sub("HTTP_", "").split("_").map(&:capitalize).join("-")}
 
 		response = {
 			method: request.request_method,
@@ -66,11 +66,11 @@ app = lambda do |env|
 			headers: headers_info
 		}
 
-		[200, {'Content-Type' => 'application/json'}, [JSON.pretty_generate(response)]]
+		[200, {"Content-Type" => "application/json"}, [JSON.pretty_generate(response)]]
 
-	when '/post'
+	when "/post"
 		# Handle POST requests
-		if request.request_method == 'POST'
+		if request.request_method == "POST"
 			# Read request body
 			body = request.body.read
 
@@ -82,30 +82,30 @@ app = lambda do |env|
 				timestamp: Time.now.iso8601
 			}
 
-			[200, {'Content-Type' => 'application/json'}, [JSON.pretty_generate(response)]]
+			[200, {"Content-Type" => "application/json"}, [JSON.pretty_generate(response)]]
 		else
-			[405, {'Content-Type' => 'text/plain'}, ['Method Not Allowed - Use POST']]
+			[405, {"Content-Type" => "text/plain"}, ["Method Not Allowed - Use POST"]]
 		end
 
-	when '/error'
+	when "/error"
 		# Generate an error for testing error recording
 		raise "Intentional error for testing"
 
-	when '/slow'
+	when "/slow"
 		# Simulate a slow response
 		sleep(1)
-		[200, {'Content-Type' => 'text/plain'}, ["Slow response after 1 second delay"]]
+		[200, {"Content-Type" => "text/plain"}, ["Slow response after 1 second delay"]]
 
 	else
 		# 404 Not Found
-		[404, {'Content-Type' => 'text/plain'}, ['Not Found']]
+		[404, {"Content-Type" => "text/plain"}, ["Not Found"]]
 	end
 end
 
 # If running with plain rackup (not Falcon), we can add the middleware here
 # But when using Falcon with falcon.rb, the middleware is configured there
-if ENV['CAPTURE_ENABLED'] == 'true'
-	require 'async/http/capture'
+if ENV["CAPTURE_ENABLED"] == "true"
+	require "async/http/capture"
 
 	# Create stores for recording
 	store = Async::HTTP::Capture::CassetteStore.new("recordings")

diff --git a/examples/recorder/falcon.rb b/examples/recorder/falcon.rb
@@ -8,12 +8,12 @@
 # Configure the host and port for the server
 service "recorder-example" do
 	include Falcon::Environment::Application
-
+	
 	# Bind to localhost on port 9292
 	endpoint Async::HTTP::Endpoint.parse(
 		"http://localhost:9292"
 	)
-
+	
 	# This is where we set up the recording middleware
 	# The middleware will automatically capture all requests and responses
 	middleware do
@@ -28,24 +28,24 @@
 			store.call(interaction)
 			console_store.call(interaction)
 		end
-
+		
 		application = Protocol::HTTP::Middleware.build do
 			run ::Protocol::HTTP::Middleware::HelloWorld
 		end
-
+		
 		middleware = Async::HTTP::Capture::Middleware.new(
 			application,
 			store: combined_store
 		)
-
+		
 		# Replay interactions:
 		cassette = store.cassette
 		cassette.each do |interaction|
 			puts "Replaying interaction: #{interaction}"
 			response = application.call(interaction.request)
 			response.finish
 		end
-
+		
 		middleware
 	end
 end
diff --git a/examples/recorder/gems.rb b/examples/recorder/gems.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 source "https://rubygems.org"
 
 gem "falcon"

diff --git a/lib/async/http/capture/interaction.rb b/lib/async/http/capture/interaction.rb
@@ -90,7 +90,7 @@ def serialize
 
 					data
 				end
-
+				
 				# Provide a reasonable string representation of this interaction.
 				# @returns [String] A human-readable description of the interaction.
 				def to_s

diff --git a/lib/async/http/capture/middleware.rb b/lib/async/http/capture/middleware.rb
@@ -29,6 +29,11 @@ def initialize(app, store:)
 				# @parameter request [Protocol::HTTP::Request] The incoming HTTP request.
 				# @returns [Protocol::HTTP::Response] The response from the next middleware.
 				def call(request)
+					# Check if we should capture this request:
+					unless capture?(request)
+						return super(request)
+					end
+
 					# Create completion tracker for this interaction:
 					tracker = create_interaction_tracker(request)
 
@@ -42,6 +47,14 @@ def call(request)
 					capture_response_with_completion(captured_request, response, tracker)
 				end
 
+				# Determine whether to capture the given request.
+				# Override this method in subclasses to implement custom filtering logic.
+				# @parameter request [Protocol::HTTP::Request] The incoming HTTP request.
+				# @returns [Boolean] True if the request should be captured, false otherwise.
+				def capture?(request)
+					true
+				end
+
 				private
 
 				# Create a completion tracker for a single interaction.

diff --git a/test/async/http/capture/middleware.rb b/test/async/http/capture/middleware.rb
@@ -191,4 +191,82 @@
 			expect(interaction.to_h[:response][:status]).to be == 200
 		end
 	end
+
+	with "#capture?" do
+		let(:get_request) do
+			Protocol::HTTP::Request["GET", "/test", {"User-Agent" => "Test"}]
+		end
+
+		let(:post_request) do
+			Protocol::HTTP::Request[
+				"POST",
+				"/users",
+				{"Content-Type" => "application/json"},
+				['{"name": "John"}']
+			]
+		end
+
+		let(:selective_middleware) do
+			Class.new(subject) do
+				def initialize(app, store:)
+					super(app, store: store)
+					@captured_requests = []
+				end
+
+				# Custom filtering logic: only capture GET requests
+				def capture?(request)
+					request.method == "GET"
+				end
+			end
+		end
+
+		it "defaults to true for base middleware" do
+			middleware = subject.new(simple_app, store: cassette_store)
+			expect(middleware.capture?(get_request)).to be == true
+			expect(middleware.capture?(post_request)).to be == true
+		end
+
+		it "can be overridden to filter requests" do
+			middleware = selective_middleware.new(simple_app, store: cassette_store)
+			expect(middleware.capture?(get_request)).to be == true
+			expect(middleware.capture?(post_request)).to be == false
+		end
+
+		it "skips capturing when capture? returns false" do
+			middleware = selective_middleware.new(simple_app, store: cassette_store)
+
+			# Make a POST request - should not be captured
+			response = middleware.call(post_request)
+			response.body.each {|chunk|} if response.body # Consume body
+
+			# Verify no interactions were recorded:
+			expect(File).not.to be(:directory?, cassette_path)
+
+			# Make a GET request - should be captured
+			response = middleware.call(get_request)
+			response.body.each {|chunk|} if response.body # Consume body
+
+			# Verify one interaction was recorded:
+			expect(File).to be(:directory?, cassette_path)
+			cassette = Async::HTTP::Capture::Cassette.load(cassette_path)
+			expect(cassette.interactions).to have_attributes(length: be == 1)
+			expect(cassette.interactions.first.to_h[:request][:method]).to be == "GET"
+		end
+
+		it "still processes requests normally when not capturing" do
+			middleware = selective_middleware.new(echo_app, store: cassette_store)
+
+			# POST request should not be captured but should still work normally
+			response = middleware.call(post_request)
+
+			# Echo app should still return the request body:
+			body_content = []
+			response.body.each {|chunk| body_content << chunk}
+			expect(body_content).to be == ['{"name": "John"}']
+			expect(response.status).to be == 200
+
+			# But no interaction should be recorded:
+			expect(File).not.to be(:directory?, cassette_path)
+		end
+	end
 end
-Original file line number
+Diff line change
@@ Expand Up / @@ -90,7 +90,7 @@ def serialize @@
     					data
     				end
     				# Provide a reasonable string representation of this interaction.
     				# @returns [String] A human-readable description of the interaction.
     				def to_s
@@ Expand Down @@