Implement llparser binding for http parsing

Author: midnight-wonderer

http.gemspec

@@ -31,6 +31,7 @@ Gem::Specification.new do |gem|
   gem.add_runtime_dependency "http-cookie",    "~> 1.0"
   gem.add_runtime_dependency "http-form_data", "~> 2.2"
   gem.add_runtime_dependency "http-parser",    "~> 1.2.0"
+  gem.add_runtime_dependency "llhttp"
 
   gem.add_development_dependency "bundler", "~> 2.0"
 

lib/http/connection.rb

@@ -3,7 +3,7 @@
 require "forwardable"
 
 require "http/headers"
-require "http/response/parser"
+require "http/response/llparser"
 
 module HTTP
   # A connection to the HTTP server
@@ -37,7 +37,7 @@ def initialize(req, options)
       @failed_proxy_connect = false
       @buffer               = "".b
 
-      @parser = Response::Parser.new
+      @parser = Response::LLParser.new
 
       @socket = options.timeout_class.new(options.timeout_options)
       @socket.connect(options.socket_class, req.socket_host, req.socket_port, options.nodelay)

lib/http/response/llparser.rb

@@ -0,0 +1,125 @@
+# frozen_string_literal: true
+
+require "llhttp"
+
+module HTTP
+  class Response
+    # @api private
+
+    class LLParsingHandler < ::LLHttp::Delegate
+      def initialize(target)
+        @target = target
+        super()
+        reset
+      end
+
+      def reset
+        @header_field = nil
+      end
+
+      def on_header_field(field)
+        @header_field = field
+      end
+
+      def on_header_value(value)
+        return unless @header_field
+        @target.add_header(@header_field, value)
+        @header_field = nil
+      end
+
+      def on_headers_complete
+        @target.status_code = @target.parser.status_code
+        @target.http_version = "#{@target.parser.http_major}.#{@target.parser.http_minor}"
+        @target.mark_header_finished
+      end
+
+      def on_body(body)
+        @target.add_body(body)
+      end
+
+      def on_message_complete
+        @target.mark_message_finished
+      end
+    end
+
+    class LLParser
+      attr_reader \
+        :parser,
+        :headers
+      attr_accessor \
+        :status_code,
+        :http_version
+
+      def initialize
+        @parsing_handler = LLParsingHandler.new(self)
+        @parser = ::LLHttp::Parser.new(
+          @parsing_handler,
+          type: :response
+        )
+        reset
+      end
+
+      def reset
+        @parsing_handler.reset
+        @header_finished = false
+        @message_finished = false
+        @headers = Headers.new
+        @body_buffer&.close
+        @body_buffer&.clear
+        @body_buffer = ::Queue.new
+        @read_buffer = ""
+      end
+
+      # @return [self]
+      def add(data)
+        (parser << data).tap do |success|
+          raise IOError, "Could not parse data" unless success
+          break self
+        end
+      end
+
+      alias << add
+
+      def mark_header_finished
+        @header_finished = true
+      end
+
+      def headers?
+        @header_finished
+      end
+
+      def add_header(name, value)
+        @headers.add(name, value)
+      end
+
+      def mark_message_finished
+        @message_finished = true
+        @body_buffer.close if @body_buffer.respond_to?(:close)
+      end
+
+      def finished?
+        @message_finished
+      end
+
+      def add_body(chunk)
+        @body_buffer.enq(chunk)
+      end
+
+      def read(size)
+        loop do
+          # puts 'looping'
+          @read_buffer = "#{@read_buffer}#{@body_buffer.deq(true)}"
+          break if size <= @read_buffer.bytesize
+        rescue ::StopIteration, ::ThreadError
+          break
+        end
+        @read_buffer.byteslice(0, size).tap do |chunk|
+          @read_buffer = @read_buffer.byteslice(
+            (size)...(@read_buffer.bytesize)
+          ) || ""
+          break nil if chunk.empty?
+        end
+      end
+    end
+  end
+end