Retry remote HTTP/2 internal errors

Author: samuel-williams-shopify

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", "~> 0.14"
-	spec.add_dependency "protocol-http", "~> 0.64"
+	spec.add_dependency "protocol-http", "~> 0.66"
 	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

@@ -9,6 +9,7 @@
 require "async/pool/controller"
 
 require "protocol/http/body/completable"
+require "protocol/http/error"
 require "protocol/http/methods"
 
 require_relative "protocol"
@@ -126,7 +127,7 @@ def call(request)
 					else
 						raise
 					end
-				rescue SocketError, IOError, EOFError, Errno::ECONNRESET, Errno::EPIPE
+				rescue ::Protocol::HTTP::RemoteError, SocketError, IOError, EOFError, Errno::ECONNRESET, Errno::EPIPE
 					if connection
 						@pool.release(connection)
 						connection = nil

lib/async/http/protocol/http2/client.rb

@@ -54,6 +54,12 @@ def write_request(response, request)
 					# @parameter response [Response] The response to wait on.
 					def read_response(response)
 						response.wait
+					rescue ::Protocol::HTTP2::StreamError => error
+						if error.code == ::Protocol::HTTP2::Error::INTERNAL_ERROR
+							raise ::Protocol::HTTP::RemoteError.new(error.message), cause: error
+						end
+						
+						raise
 					end
 				end
 			end

releases.md

@@ -1,5 +1,9 @@
 # Releases
 
+## Unreleased
+
+  - Retry safe requests when a remote HTTP/2 endpoint resets the stream with `INTERNAL_ERROR` before returning a response.
+
 ## v0.98.1
 
   - Probe idle HTTP/1 connections before reuse, avoiding requests on connections already closed by the peer.

test/async/http/client/retry.rb

@@ -50,6 +50,27 @@ def make_response(request, connection, attempt)
 			expect(client.chunks).to be == ["Hello", "Hello"]
 		end
 
+		it "rewinds idempotent request bodies after remote failures" do
+			client = RetryClient.new([Protocol::HTTP::RemoteError.new("Remote endpoint failed.")])
+			request = Protocol::HTTP::Request["PUT", "/", {}, ["Hello"]]
+			
+			response = client.call(request)
+			
+			expect(response).to be(:success?)
+			expect(client.chunks).to be == ["Hello", "Hello"]
+		end
+		
+		it "does not retry non-idempotent requests after remote failures" do
+			client = RetryClient.new([Protocol::HTTP::RemoteError.new("Remote endpoint failed.")])
+			request = Protocol::HTTP::Request["POST", "/", {}, ["Hello"]]
+			
+			expect do
+				client.call(request)
+			end.to raise_exception(Protocol::HTTP::RemoteError)
+			
+			expect(client.chunks).to be == ["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"]]

test/async/http/protocol/http2/connection_close_with_active_streams.rb

@@ -49,6 +49,26 @@
 			end.wait
 		end
 
+		it "maps a remote internal error while waiting for headers" do
+			Async do |task|
+				client_connection = Async::HTTP::Protocol::HTTP2::Client.new(client_stream)
+				client_connection.open!
+				
+				response = client_connection.create_response
+				response.stream.close!(Protocol::HTTP2::INTERNAL_ERROR)
+				
+				expect do
+					client_connection.read_response(response)
+				end.to raise_exception(Protocol::HTTP::RemoteError).and(
+					have_attributes(
+						cause: be_a(Protocol::HTTP2::StreamError).and(
+							have_attributes(code: be == Protocol::HTTP2::INTERNAL_ERROR)
+						)
+					)
+				)
+			end.wait
+		end
+		
 		it "does not raise error when connection closes without active streams" do
 			Async do |task|
 				# Create client connection