Rewind request bodies before retry. (#229)

Author: ioquatix

async-http.gemspec

@@ -28,7 +28,7 @@ Gem::Specification.new do |spec|
 	spec.add_dependency "async-pool", "~> 0.11"
 	spec.add_dependency "io-endpoint", "~> 0.14"
 	spec.add_dependency "io-stream", "~> 0.6"
-	spec.add_dependency "protocol-http", "~> 0.62"
+	spec.add_dependency "protocol-http", "~> 0.64"
 	spec.add_dependency "protocol-http1", "~> 0.39"
 	spec.add_dependency "protocol-http2", "~> 0.26"
 	spec.add_dependency "protocol-url", "~> 0.2"

lib/async/http/client.rb

@@ -121,7 +121,7 @@ def call(request)
 						connection = nil
 					end
 
-					if attempt < @retries
+					if attempt < @retries and request.rewind!
 						retry
 					else
 						raise
@@ -132,7 +132,7 @@ def call(request)
 						connection = nil
 					end
 
-					if request.idempotent? and attempt < @retries
+					if attempt < @retries and request.retry!
 						retry
 					else
 						raise

releases.md

@@ -1,5 +1,9 @@
 # Releases
 
+## Unreleased
+
+  - Rewind request bodies before retrying requests.
+
 ## v0.97.0
 
   - Exposed all supported protocol names from the plaintext HTTP protocol negotiator.

test/async/http/client/retry.rb

@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2026, by Samuel Williams.
+
+require "async/http/client"
+
+class RetryClient < Async::HTTP::Client
+	def initialize(failures)
+		@pool = FakePool.new
+		@protocol = nil
+		@retries = 3
+		@scheme = "https"
+		@authority = "example.com"
+		@failures = failures
+		@chunks = []
+	end
+	
+	attr :chunks
+	
+	class FakePool
+		def acquire
+			Object.new
+		end
+		
+		def release(connection)
+		end
+	end
+	
+	def make_response(request, connection, attempt)
+		@chunks << request.body&.read
+		
+		if failure = @failures.shift
+			raise failure
+		end
+		
+		return Protocol::HTTP::Response[200, {}, ["OK"]]
+	end
+end
+
+describe Async::HTTP::Client do
+	with "retries" do
+		it "rewinds idempotent request bodies after ambiguous failures" do
+			client = RetryClient.new([EOFError.new])
+			request = Protocol::HTTP::Request["PUT", "/", {}, ["Hello"]]
+			
+			response = client.call(request)
+			
+			expect(response).to be(:success?)
+			expect(client.chunks).to be == ["Hello", "Hello"]
+		end
+		
+		it "rewinds non-idempotent request bodies after refused requests" do
+			client = RetryClient.new([Protocol::HTTP::RefusedError.new("Request not processed.")])
+			request = Protocol::HTTP::Request["POST", "/", {}, ["Hello"]]
+			
+			response = client.call(request)
+			
+			expect(response).to be(:success?)
+			expect(client.chunks).to be == ["Hello", "Hello"]
+		end
+	end
+end