add chain

pkg/components/dialer/dialer.go

@@ -0,0 +1,19 @@
+package dialer
+
+import (
+	"context"
+	"net"
+)
+
+// Transporter is responsible for dialing to the proxy server.
+type Dialer interface {
+	Dial(ctx context.Context, addr string, opts ...DialOption) (net.Conn, error)
+}
+
+type Handshaker interface {
+	Handshake(ctx context.Context, conn net.Conn) (net.Conn, error)
+}
+
+type Multiplexer interface {
+	IsMultiplex() bool
+}

pkg/components/dialer/metadata.go

@@ -0,0 +1,3 @@
+package dialer
+
+type Metadata map[string]string

pkg/components/dialer/option.go

@@ -0,0 +1,32 @@
+package dialer
+
+import (
+	"context"
+	"net"
+
+	"github.com/go-gost/gost/pkg/logger"
+)
+
+type Options struct {
+	Logger logger.Logger
+}
+
+type Option func(opts *Options)
+
+func LoggerOption(logger logger.Logger) Option {
+	return func(opts *Options) {
+		opts.Logger = logger
+	}
+}
+
+type DialOptions struct {
+	DialFunc func(ctx context.Context, addr string) (net.Conn, error)
+}
+
+type DialOption func(opts *DialOptions)
+
+func DialFuncDialOption(dialf func(ctx context.Context, addr string) (net.Conn, error)) DialOption {
+	return func(opts *DialOptions) {
+		opts.DialFunc = dialf
+	}
+}

pkg/components/dialer/tcp/dialer.go

@@ -0,0 +1,56 @@
+package tcp
+
+import (
+	"context"
+	"net"
+
+	"github.com/go-gost/gost/pkg/components/dialer"
+	"github.com/go-gost/gost/pkg/logger"
+)
+
+var (
+	_ dialer.Dialer = (*Dialer)(nil)
+)
+
+type Dialer struct {
+	md     metadata
+	logger logger.Logger
+}
+
+func NewDialer(opts ...dialer.Option) *Dialer {
+	options := &dialer.Options{}
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	return &Dialer{
+		logger: options.Logger,
+	}
+}
+
+func (d *Dialer) Init(md dialer.Metadata) (err error) {
+	d.md, err = d.parseMetadata(md)
+	if err != nil {
+		return
+	}
+	return nil
+}
+
+func (d *Dialer) Dial(ctx context.Context, addr string, opts ...dialer.DialOption) (net.Conn, error) {
+	var options dialer.DialOptions
+	for _, opt := range opts {
+		opt(&options)
+	}
+
+	dial := options.DialFunc
+	if dial != nil {
+		return dial(ctx, addr)
+	}
+
+	var netd net.Dialer
+	return netd.DialContext(ctx, "tcp", addr)
+}
+
+func (d *Dialer) parseMetadata(md dialer.Metadata) (m metadata, err error) {
+	return
+}

pkg/components/dialer/tcp/metadata.go

@@ -0,0 +1,15 @@
+package tcp
+
+import "time"
+
+const (
+	dialTimeout = "dialTimeout"
+)
+
+const (
+	defaultDialTimeout = 5 * time.Second
+)
+
+type metadata struct {
+	dialTimeout time.Duration
+}