gistfile1.txt

package client

import (
	"bufio"
	"crypto/tls"
	"fmt"
	"net"
	"net/http"
)

type OrderedHTTPResponse struct {
	Response *http.Response
	Err      error
}

type work struct {
	req *http.Request
	c   chan *OrderedHTTPResponse
}

type OrderedHTTPClient struct {
	conn net.Conn
	out  chan *work
	in   chan *work
}

func NewOrderedHTTPClient(host string) (*OrderedHTTPClient, error) {
	conn, err := tls.Dial("tcp", host, nil)
	if err != nil {
		return nil, err
	}
	client := &OrderedHTTPClient{
		conn: conn,
		out:  make(chan *work, 100),
		in:   make(chan *work, 100),
	}
	go client.writePump()
	go client.readPump()
	return client, nil
}

func (c *OrderedHTTPClient) Close() {
	close(c.out)
	close(c.in)
}

func (c *OrderedHTTPClient) writePump() {
	for job := range c.out {
		if err := job.req.Write(c.conn); err != nil {
			job.c <- &OrderedHTTPResponse{Err: fmt.Errorf("write: %v", err)}
			continue
		}
		c.in <- job
	}
}

func (c *OrderedHTTPClient) readPump() {
	defer c.conn.Close()
	r := bufio.NewReader(c.conn)
	for job := range c.in {
		resp, err := http.ReadResponse(r, job.req)
		if err != nil {
			job.c <- &OrderedHTTPResponse{Err: fmt.Errorf("read: %v", err)}
		} else {
			job.c <- &OrderedHTTPResponse{Response: resp}
		}
	}
}

func (c *OrderedHTTPClient) Do(req *http.Request) chan *OrderedHTTPResponse {
	job := &work{
		req: req,
		c:   make(chan *OrderedHTTPResponse, 1),
	}
	c.out <- job
	return job.c
}