From 26af20b7054c0518d160958bb7b5d09e0b2e5b3c Mon Sep 17 00:00:00 2001
From: fangdingjun <fangdingjun@gmail.com>
Date: Mon, 13 Aug 2018 09:57:28 +0800
Subject: [PATCH] add nghttp2.Transport

---
 client.go | 85 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 85 insertions(+)
 create mode 100644 client.go

diff --git a/client.go b/client.go
new file mode 100644
index 0000000..d872cf6
--- /dev/null
+++ b/client.go
@@ -0,0 +1,85 @@
+package nghttp2
+
+import (
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"net/http"
+	"strings"
+	"sync"
+)
+
+// Transport the nghttp2 RoundTripper implement
+type Transport struct {
+	TLSConfig *tls.Config
+	DialTLS   func(network, addr string, cfg *tls.Config) (*tls.Conn, error)
+	cacheConn map[string]*Conn
+	mu        sync.Mutex
+}
+
+// RoundTrip send req and get res
+func (tr *Transport) RoundTrip(req *http.Request) (res *http.Response, err error) {
+	h2conn, err := tr.getConn(req)
+	if err != nil {
+		return nil, err
+	}
+	return h2conn.RoundTrip(req)
+}
+
+func (tr *Transport) getConn(req *http.Request) (*Conn, error) {
+	tr.mu.Lock()
+	defer tr.mu.Unlock()
+
+	if tr.cacheConn == nil {
+		tr.cacheConn = map[string]*Conn{}
+	}
+	k := req.URL.Host
+	if c, ok := tr.cacheConn[k]; ok {
+		if c.CanTakeNewRequest() {
+			return c, nil
+		}
+		delete(tr.cacheConn, k)
+		c.Close()
+	}
+	c, err := tr.createConn(k)
+	if err == nil {
+		tr.cacheConn[k] = c
+	}
+	return c, err
+}
+
+func (tr *Transport) createConn(host string) (*Conn, error) {
+	dial := tls.Dial
+	if tr.DialTLS != nil {
+		dial = tr.DialTLS
+	}
+	cfg := tr.TLSConfig
+	if cfg == nil {
+		h, _, err := net.SplitHostPort(host)
+		if err != nil {
+			h = host
+		}
+		cfg = &tls.Config{
+			ServerName: h,
+			NextProtos: []string{"h2"},
+		}
+	}
+	if !strings.Contains(host, ":") {
+		host = fmt.Sprintf("%s:443", host)
+	}
+	conn, err := dial("tcp", host, cfg)
+	if err != nil {
+		return nil, err
+	}
+	if err = conn.Handshake(); err != nil {
+		return nil, err
+	}
+	state := conn.ConnectionState()
+	if state.NegotiatedProtocol != "h2" {
+		conn.Close()
+		return nil, errors.New("http2 is not supported")
+	}
+
+	return Client(conn)
+}