feat: add plugin

http2/http.go

@@ -2,96 +2,18 @@
 package http2
 
 import (
-	"context"
-	"crypto/tls"
-	"errors"
 	"io"
-	"net"
 	"net/http"
 	"net/url"
-	"time"
 
-	"golang.org/x/net/http2"
-
-	"github.com/fumiama/terasu"
 	"github.com/fumiama/terasu/dns"
+	"golang.org/x/net/http2"
 )
 
-// ErrEmptyHostAddress is returned when DNS lookup for a host returns no addresses
-var ErrEmptyHostAddress = errors.New("empty host addr")
-
-// defaultDialer is the default dialer used for establishing TCP connections
-var defaultDialer = net.Dialer{
-	Timeout: 10 * time.Second,
-}
-
-// SetDefaultClientTimeout sets the default timeout for all HTTP2 client connections
-func SetDefaultClientTimeout(t time.Duration) {
-	defaultDialer.Timeout = t
-}
-
 // DefaultClient is the default HTTP2 client that supports HTTP/2 and DNS resolution
 var DefaultClient = http.Client{
 	Transport: &http2.Transport{
-		DialTLSContext: func(ctx context.Context, network, addr string, cfg *tls.Config) (net.Conn, error) {
-			host, port, err := net.SplitHostPort(addr)
-			if err != nil {
-				return nil, err
-			}
-			addrs, err := dns.LookupHost(ctx, host)
-			if err != nil {
-				return nil, err
-			}
-			if len(addrs) == 0 {
-				return nil, ErrEmptyHostAddress
-			}
-			var conn net.Conn
-			var tlsConn *tls.Conn
-			for _, a := range addrs {
-				if defaultDialer.Timeout != 0 {
-					var cancel context.CancelFunc
-					ctx, cancel = context.WithTimeout(context.Background(), defaultDialer.Timeout)
-					defer cancel()
-				} else if !defaultDialer.Deadline.IsZero() {
-					var cancel context.CancelFunc
-					ctx, cancel = context.WithDeadline(context.Background(), defaultDialer.Deadline)
-					defer cancel()
-				}
-				conn, err = defaultDialer.DialContext(ctx, network, net.JoinHostPort(a, port))
-				if err != nil {
-					continue
-				}
-				tlsConn = tls.Client(terasu.NewConn(conn), cfg)
-				// re-init ctx due to deadline settings in tcp dial
-				if defaultDialer.Timeout != 0 {
-					var cancel context.CancelFunc
-					ctx, cancel = context.WithTimeout(context.Background(), defaultDialer.Timeout)
-					defer cancel()
-				} else if !defaultDialer.Deadline.IsZero() {
-					var cancel context.CancelFunc
-					ctx, cancel = context.WithDeadline(context.Background(), defaultDialer.Deadline)
-					defer cancel()
-				}
-				err = tlsConn.HandshakeContext(ctx)
-				if err == nil {
-					break
-				}
-				_ = tlsConn.Close()
-				tlsConn = nil
-				conn, err = defaultDialer.DialContext(ctx, network, net.JoinHostPort(a, port))
-				if err != nil {
-					continue
-				}
-				tlsConn = tls.Client(terasu.NewConn(conn), cfg)
-				err = tlsConn.HandshakeContext(ctx)
-				if err == nil {
-					break
-				}
-				_ = tlsConn.Close()
-				tlsConn = nil
-			}
-			return tlsConn, err
-		},
+		DialTLSContext: dns.DialTLSContextWithConfig,
 	},
 }