support fetching config from http

common/buf/multi_buffer.go

@@ -6,6 +6,7 @@ import (
 
 	"v2ray.com/core/common"
 	"v2ray.com/core/common/errors"
+	"v2ray.com/core/common/serial"
 )
 
 // ReadAllToMultiBuffer reads all content from the reader into a MultiBuffer, until EOF.
@@ -102,6 +103,9 @@ func (mb MultiBuffer) Copy(b []byte) int {
 
 // Read implements io.Reader.
 func (mb *MultiBuffer) Read(b []byte) (int, error) {
+	if mb.Len() == 0 {
+		return 0, io.EOF
+	}
 	endIndex := len(*mb)
 	totalBytes := 0
 	for i, bb := range *mb {
@@ -121,7 +125,9 @@ func (mb *MultiBuffer) Read(b []byte) (int, error) {
 }
 
 // Write implements io.Writer.
-func (mb *MultiBuffer) Write(b []byte) {
+func (mb *MultiBuffer) Write(b []byte) (int, error) {
+	totalBytes := len(b)
+
 	n := len(*mb)
 	if n > 0 && !(*mb)[n-1].IsFull() {
 		nBytes, _ := (*mb)[n-1].Write(b)
@@ -134,6 +140,8 @@ func (mb *MultiBuffer) Write(b []byte) {
 		b = b[nBytes:]
 		mb.Append(bb)
 	}
+
+	return totalBytes, nil
 }
 
 // Len returns the total number of bytes in the MultiBuffer.
@@ -164,6 +172,14 @@ func (mb *MultiBuffer) Release() {
 	*mb = nil
 }
 
+func (mb MultiBuffer) String() string {
+	v := make([]interface{}, len(mb))
+	for i, b := range mb {
+		v[i] = b
+	}
+	return serial.Concat(v...)
+}
+
 // ToNetBuffers converts this MultiBuffer to net.Buffers. The return net.Buffers points to the same content of the MultiBuffer.
 func (mb MultiBuffer) ToNetBuffers() net.Buffers {
 	bs := make([][]byte, len(mb))

common/buf/reader.go

@@ -3,6 +3,7 @@ package buf
 import (
 	"io"
 
+	"v2ray.com/core/common"
 	"v2ray.com/core/common/errors"
 )
 
@@ -52,7 +53,7 @@ func (r *BytesToBufferReader) ReadMultiBuffer() (MultiBuffer, error) {
 	nBytes, err := r.Reader.Read(r.buffer)
 	if nBytes > 0 {
 		mb := NewMultiBufferCap(int32(nBytes/Size) + 1)
-		mb.Write(r.buffer[:nBytes])
+		common.Must2(mb.Write(r.buffer[:nBytes]))
 		if nBytes == len(r.buffer) && nBytes < int(largeSize) {
 			freeBytes(r.buffer)
 			r.buffer = newBytes(int32(nBytes) + 1)

common/platform/ctlcmd/attr_other.go

@@ -1,6 +1,6 @@
 // +build !windows
 
-package json
+package ctlcmd
 
 import "syscall"
 

common/platform/ctlcmd/attr_windows.go

@@ -1,6 +1,6 @@
 // +build windows
 
-package json
+package ctlcmd
 
 import "syscall"
 

common/platform/ctlcmd/ctlcmd.go

@@ -0,0 +1,67 @@
+package ctlcmd
+
+import (
+	"context"
+	"io"
+	"os"
+	"os/exec"
+
+	"v2ray.com/core/common/buf"
+	"v2ray.com/core/common/platform"
+	"v2ray.com/core/common/signal"
+)
+
+//go:generate go run $GOPATH/src/v2ray.com/core/common/errors/errorgen/main.go -pkg ctlcmd -path Command,Platform,CtlCmd
+
+func Run(args []string, input io.Reader) (buf.MultiBuffer, error) {
+	v2ctl := platform.GetToolLocation("v2ctl")
+	if _, err := os.Stat(v2ctl); err != nil {
+		return nil, err
+	}
+
+	errBuffer := &buf.MultiBuffer{}
+
+	cmd := exec.Command(v2ctl, args...)
+	cmd.Stderr = errBuffer
+	cmd.SysProcAttr = getSysProcAttr()
+	if input != nil {
+		cmd.Stdin = input
+	}
+
+	stdoutReader, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, err
+	}
+	defer stdoutReader.Close()
+
+	if err := cmd.Start(); err != nil {
+		return nil, err
+	}
+
+	var content buf.MultiBuffer
+	loadTask := signal.ExecuteAsync(func() error {
+		c, err := buf.ReadAllToMultiBuffer(stdoutReader)
+		if err != nil {
+			return err
+		}
+		content = c
+		return nil
+	})
+
+	waitTask := signal.ExecuteAsync(func() error {
+		if err := cmd.Wait(); err != nil {
+			msg := "failed to execute v2ctl"
+			if errBuffer.Len() > 0 {
+				msg += ": " + errBuffer.String()
+			}
+			return newError(msg).Base(err)
+		}
+		return nil
+	})
+
+	if err := signal.ErrorOrFinish2(context.Background(), loadTask, waitTask); err != nil {
+		return nil, err
+	}
+
+	return content, nil
+}

common/platform/ctlcmd/errors.generated.go

@@ -0,0 +1,5 @@
+package ctlcmd
+
+import "v2ray.com/core/common/errors"
+
+func newError(values ...interface{}) *errors.Error { return errors.New(values...).Path("Command", "Platform", "CtlCmd") }

main/json/config_json.go

@@ -3,79 +3,23 @@ package json
 //go:generate go run $GOPATH/src/v2ray.com/core/common/errors/errorgen/main.go -pkg json -path Main,Json
 
 import (
-	"context"
 	"io"
-	"os"
-	"os/exec"
 
 	"v2ray.com/core"
 	"v2ray.com/core/common"
-	"v2ray.com/core/common/platform"
+	"v2ray.com/core/common/platform/ctlcmd"
-	"v2ray.com/core/common/signal"
 )
 
-type logWriter struct{}
-
-func (*logWriter) Write(b []byte) (int, error) {
-	n, err := os.Stderr.Write(b)
-	if err == nil {
-		os.Stderr.WriteString(platform.LineSeparator())
-	}
-	return n, err
-}
-
-func jsonToProto(input io.Reader) (*core.Config, error) {
-	v2ctl := platform.GetToolLocation("v2ctl")
-	if _, err := os.Stat(v2ctl); err != nil {
-		return nil, err
-	}
-	cmd := exec.Command(v2ctl, "config")
-	cmd.Stdin = input
-	cmd.Stderr = &logWriter{}
-	cmd.SysProcAttr = getSysProcAttr()
-
-	stdoutReader, err := cmd.StdoutPipe()
-	if err != nil {
-		return nil, err
-	}
-	defer stdoutReader.Close()
-
-	if err := cmd.Start(); err != nil {
-		return nil, err
-	}
-
-	var config *core.Config
-
-	loadTask := signal.ExecuteAsync(func() error {
-		c, err := core.LoadConfig("protobuf", "", stdoutReader)
-		if err != nil {
-			return err
-		}
-		config = c
-		return nil
-	})
-
-	waitTask := signal.ExecuteAsync(func() error {
-		return cmd.Wait()
-	})
-
-	if err := signal.ErrorOrFinish2(context.Background(), loadTask, waitTask); err != nil {
-		return nil, err
-	}
-
-	return config, nil
-}
-
 func init() {
 	common.Must(core.RegisterConfigLoader(&core.ConfigFormat{
 		Name:      "JSON",
 		Extension: []string{"json"},
 		Loader: func(input io.Reader) (*core.Config, error) {
-			config, err := jsonToProto(input)
+			jsonContent, err := ctlcmd.Run([]string{"config"}, input)
 			if err != nil {
 				return nil, newError("failed to execute v2ctl to convert config file.").Base(err).AtWarning()
 			}
-			return config, nil
+			return core.LoadConfig("protobuf", "", &jsonContent)
 		},
 	}))
 }

main/main.go

@@ -14,6 +14,7 @@ import (
 
 	"v2ray.com/core"
 	"v2ray.com/core/common/platform"
+	"v2ray.com/core/common/platform/ctlcmd"
 	_ "v2ray.com/core/main/distro/all"
 )
 
@@ -63,6 +64,12 @@ func startV2Ray() (core.Server, error) {
 	var configInput io.Reader
 	if configFile == "stdin:" {
 		configInput = os.Stdin
+	} else if strings.HasPrefix(configFile, "http://") || strings.HasPrefix(configFile, "https://") {
+		content, err := ctlcmd.Run([]string{"fetch", configFile}, nil)
+		if err != nil {
+			return nil, err
+		}
+		configInput = &content
 	} else {
 		fixedFile := os.ExpandEnv(configFile)
 		file, err := os.Open(fixedFile)