Add support for Delve debugger

README.md

@@ -1,3 +1,4 @@
+
 bee
 ===
 
@@ -34,17 +35,20 @@ go get -u github.com/beego/bee
 Bee provides a variety of commands which can be helpful at various stages of development. The top level commands include:
 
 ```
-    new         Creates a Beego application
-    run         Run the application by starting a local development server
-    pack        Compresses a Beego application into a single file
-    api         Creates a Beego API application
-    hprose      Creates an RPC application based on Hprose and Beego frameworks
-    bale        Transforms non-Go files to Go source files
     version     Prints the current Bee version
-    generate    Source code generator
     migrate     Runs database migrations
+    api         Creates a Beego API application
+    bale        Transforms non-Go files to Go source files
     fix         Fixes your application by making it compatible with newer versions of Beego
+    dlv         Start a debugging session using Delve
     dockerize   Generates a Dockerfile for your Beego application
+    generate    Source code generator
+    hprose      Creates an RPC application based on Hprose and Beego frameworks
+    new         Creates a Beego application
+    pack        Compresses a Beego application into a single file
+    rs          Run customized scripts
+    run         Run the application by starting a local development server
+
 ```
 
 ### bee version
@@ -298,6 +302,37 @@ ______
 
 For more information on the usage, run `bee help dockerize`.
 
+### bee dlv
+
+Bee can also help with debugging your application. To start a debugging session:
+
+```bash
+______
+| ___ \
+| |_/ /  ___   ___
+| ___ \ / _ \ / _ \
+| |_/ /|  __/|  __/
+\____/  \___| \___| v1.8.0
+2017/03/22 11:17:05 INFO     ▶ 0001 Starting Delve Debugger...
+Type 'help' for list of commands.
+(dlv) break main.main
+Breakpoint 1 set at 0x40100f for main.main() ./main.go:8
+
+(dlv) continue
+> main.main() ./main.go:8 (hits goroutine(1):1 total:1) (PC: 0x40100f)
+     3:	import (
+     4:		_ "github.com/user/myapp/routers"
+     5:		"github.com/astaxie/beego"
+     6:	)
+     7:	
+=>   8:	func main() {
+     9:		beego.Run()
+    10:	}
+    11:
+```
+
+For more information on the usage, run `bee help dlv`.
+
 ## Shortcuts
 
 Because you'll likely type these generator commands over and over, it makes sense to create aliases:

cmd/bee.go

@@ -12,14 +12,15 @@
 // License for the specific language governing permissions and limitations
 // under the License.
 
-// Bee is a tool for developing applications based on beego framework.
+// Package cmd ...
 package cmd
 
 import (
 	"github.com/beego/bee/cmd/commands"
 	_ "github.com/beego/bee/cmd/commands/api"
 	_ "github.com/beego/bee/cmd/commands/bale"
 	_ "github.com/beego/bee/cmd/commands/beefix"
+	_ "github.com/beego/bee/cmd/commands/dlv"
 	_ "github.com/beego/bee/cmd/commands/dockerize"
 	_ "github.com/beego/bee/cmd/commands/generate"
 	_ "github.com/beego/bee/cmd/commands/hprose"

cmd/commands/dlv/dlv.go

@@ -0,0 +1,135 @@
+// Copyright 2017 bee authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"): you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations
+// under the License.
+
+// Package dlv ...
+package dlv
+
+import (
+	"flag"
+	"fmt"
+	"net"
+	"os"
+	"path/filepath"
+
+	"github.com/beego/bee/cmd/commands"
+	"github.com/beego/bee/cmd/commands/version"
+	beeLogger "github.com/beego/bee/logger"
+	"github.com/beego/bee/utils"
+	"github.com/derekparker/delve/pkg/terminal"
+	"github.com/derekparker/delve/service"
+	"github.com/derekparker/delve/service/rpc2"
+	"github.com/derekparker/delve/service/rpccommon"
+)
+
+var cmdDlv = &commands.Command{
+	CustomFlags: true,
+	UsageLine:   "dlv [-package=\"\"] [-port=8181]",
+	Short:       "Start a debugging session using Delve",
+	Long: `dlv command start a debugging session using debugging tool Delve.
+
+  To debug your application using Delve, use: {{"$ bee dlv" | bold}}
+
+  For more information on Delve: https://github.com/derekparker/delve
+`,
+	PreRun: func(cmd *commands.Command, args []string) { version.ShowShortVersionBanner() },
+	Run:    runDlv,
+}
+
+var (
+	packageName string
+	port        int
+)
+
+func init() {
+	fs := flag.NewFlagSet("dlv", flag.ContinueOnError)
+	fs.IntVar(&port, "port", 8181, "Port to listen to for clients")
+	fs.StringVar(&packageName, "package", "", "The package to debug (Must have a main package)")
+	cmdDlv.Flag = *fs
+	commands.AvailableCommands = append(commands.AvailableCommands, cmdDlv)
+}
+
+func runDlv(cmd *commands.Command, args []string) int {
+	if err := cmd.Flag.Parse(args); err != nil {
+		beeLogger.Log.Fatalf("Error parsing flags: %v", err.Error())
+	}
+
+	debugname := "debug"
+	addr := fmt.Sprintf("127.0.0.1:%d", port)
+	return runDelve(addr, debugname)
+}
+
+// runDelve runs the Delve debugger server
+func runDelve(addr, debugname string) int {
+	beeLogger.Log.Info("Starting Delve Debugger...")
+
+	err := gobuild(debugname, packageName)
+	if err != nil {
+		beeLogger.Log.Fatalf("%v", err)
+	}
+
+	fp, err := filepath.Abs("./" + debugname)
+	if err != nil {
+		beeLogger.Log.Fatalf("%v", err)
+	}
+	defer os.Remove(fp)
+
+	abs, err := filepath.Abs(debugname)
+	if err != nil {
+		beeLogger.Log.Fatalf("%v", err)
+	}
+
+	// Create and start the debugger server
+	listener, err := net.Listen("tcp", addr)
+	if err != nil {
+		beeLogger.Log.Fatalf("Could not start listener: %s", err)
+	}
+	defer listener.Close()
+
+	server := rpccommon.NewServer(&service.Config{
+		Listener:    listener,
+		AcceptMulti: true,
+		AttachPid:   0,
+		APIVersion:  2,
+		WorkingDir:  "./",
+		ProcessArgs: []string{abs},
+	}, false)
+	if err := server.Run(); err != nil {
+		beeLogger.Log.Fatalf("Could not start debugger server: %v", err)
+	}
+
+	// Start the Delve client REPL
+	client := rpc2.NewClient(addr)
+	term := terminal.New(client, nil)
+
+	status, err := term.Run()
+	if err != nil {
+		beeLogger.Log.Fatalf("Could not start Delve REPL: %v", err)
+	}
+	defer term.Close()
+
+	// Stop and kill the debugger server once
+	// user quits the REPL
+	if err := server.Stop(true); err != nil {
+		beeLogger.Log.Fatalf("Could not stop Delve server: %v", err)
+	}
+	return status
+}
+
+// gobuild runs the "go build" command on the specified package
+func gobuild(debugname, pkg string) error {
+	args := []string{"-gcflags", "-N -l", "-o", debugname}
+	args = append(args, utils.SplitQuotedFields("-ldflags='-linkmode internal'")...)
+	args = append(args, pkg)
+	return utils.GoCommand("build", args...)
+}

utils/utils.go

@@ -26,6 +26,7 @@ import (
 	"runtime"
 	"strings"
 	"text/template"
+	"unicode"
 
 	beeLogger "github.com/beego/bee/logger"
 	"github.com/beego/bee/logger/colors"
@@ -332,3 +333,69 @@ func PrintErrorAndExit(message, errorTemplate string) {
 	Tmpl(fmt.Sprintf(errorTemplate, message), nil)
 	os.Exit(2)
 }
+
+// GoCommand executes the passed command using Go tool
+func GoCommand(command string, args ...string) error {
+	allargs := []string{command}
+	allargs = append(allargs, args...)
+	goBuild := exec.Command("go", allargs...)
+	goBuild.Stderr = os.Stderr
+	return goBuild.Run()
+}
+
+// SplitQuotedFields is like strings.Fields but ignores spaces
+// inside areas surrounded by single quotes.
+// To specify a single quote use backslash to escape it: '\''
+func SplitQuotedFields(in string) []string {
+	type stateEnum int
+	const (
+		inSpace stateEnum = iota
+		inField
+		inQuote
+		inQuoteEscaped
+	)
+	state := inSpace
+	r := []string{}
+	var buf bytes.Buffer
+
+	for _, ch := range in {
+		switch state {
+		case inSpace:
+			if ch == '\'' {
+				state = inQuote
+			} else if !unicode.IsSpace(ch) {
+				buf.WriteRune(ch)
+				state = inField
+			}
+
+		case inField:
+			if ch == '\'' {
+				state = inQuote
+			} else if unicode.IsSpace(ch) {
+				r = append(r, buf.String())
+				buf.Reset()
+			} else {
+				buf.WriteRune(ch)
+			}
+
+		case inQuote:
+			if ch == '\'' {
+				state = inField
+			} else if ch == '\\' {
+				state = inQuoteEscaped
+			} else {
+				buf.WriteRune(ch)
+			}
+
+		case inQuoteEscaped:
+			buf.WriteRune(ch)
+			state = inQuote
+		}
+	}
+
+	if buf.Len() != 0 {
+		r = append(r, buf.String())
+	}
+
+	return r
+}