rpc service generation (#26)

* add execute files

* add protoc-osx

* add rpc generation

* add rpc generation

* add: rpc template generation

* update usage

* fixed env prepare for project in go path

* optimize gomod cache

* add README.md

* format error

* reactor templatex.go

* remove waste code

tools/goctl/rpc/ctx/project.go

@@ -0,0 +1,208 @@
+package ctx
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"runtime"
+	"strings"
+
+	"github.com/tal-tech/go-zero/tools/goctl/rpc/execx"
+	"github.com/tal-tech/go-zero/tools/goctl/util"
+	"github.com/tal-tech/go-zero/tools/goctl/util/console"
+)
+
+var (
+	errProtobufNotFound = errors.New("github.com/golang/protobuf is not found,please ensure you has already [go get github.com/golang/protobuf]")
+)
+
+const (
+	constGo          = "go"
+	constProtoC      = "protoc"
+	constGoModOn     = "go env GO111MODULE"
+	constGoMod       = "go env GOMOD"
+	constGoModCache  = "go env GOMODCACHE"
+	constGoPath      = "go env GOPATH"
+	constProtoCGenGo = "protoc-gen-go"
+)
+
+type (
+	Project struct {
+		Path     string
+		Name     string
+		GoPath   string
+		Protobuf Protobuf
+		GoMod    GoMod
+	}
+
+	GoMod struct {
+		ModOn      bool
+		GoModCache string
+		GoMod      string
+		Module     string
+	}
+	Protobuf struct {
+		Path string
+	}
+)
+
+func prepare(log console.Console) (*Project, error) {
+	log.Info("check go env ...")
+	_, err := exec.LookPath(constGo)
+	if err != nil {
+		return nil, err
+	}
+
+	_, err = exec.LookPath(constProtoC)
+	if err != nil {
+		return nil, err
+	}
+
+	var (
+		goModOn                   bool
+		goMod, goModCache, module string
+		goPath                    string
+		name, path                string
+		protobufModule            string
+	)
+	ret, err := execx.Run(constGoModOn)
+	if err != nil {
+		return nil, err
+	}
+
+	goModOn = strings.TrimSpace(ret) == "on"
+	ret, err = execx.Run(constGoMod)
+	if err != nil {
+		return nil, err
+	}
+
+	goMod = strings.TrimSpace(ret)
+	ret, err = execx.Run(constGoModCache)
+	if err != nil {
+		return nil, err
+	}
+
+	goModCache = strings.TrimSpace(ret)
+	ret, err = execx.Run(constGoPath)
+	if err != nil {
+		return nil, err
+	}
+
+	goPath = strings.TrimSpace(ret)
+	src := filepath.Join(goPath, "src")
+	if len(goMod) > 0 {
+		if goModCache == "" {
+			goModCache = filepath.Join(goPath, "pkg", "mod")
+		}
+		path = filepath.Dir(goMod)
+		name = filepath.Base(path)
+		data, err := ioutil.ReadFile(goMod)
+		if err != nil {
+			return nil, err
+		}
+
+		module, err = matchModule(data)
+		if err != nil {
+			return nil, err
+		}
+
+		protobufModule, err = matchProtoBuf(data)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		if goModCache == "" {
+			goModCache = src
+		}
+		pwd, err := os.Getwd()
+		if err != nil {
+			return nil, err
+		}
+
+		if !strings.HasPrefix(pwd, src) {
+			return nil, fmt.Errorf("%s: project is not in go mod and go path", pwd)
+		}
+		r := strings.TrimPrefix(pwd, src+string(filepath.Separator))
+		name = filepath.Dir(r)
+		if name == "." {
+			name = r
+		}
+		path = filepath.Join(src, name)
+		module = name
+	}
+
+	protobuf := filepath.Join(goModCache, protobufModule)
+	if !util.FileExists(protobuf) {
+		return nil, fmt.Errorf("expected protobuf module in path: %s,please ensure you has already [go get github.com/golang/protobuf]", protobuf)
+	}
+
+	var protoCGenGoFilename string
+	os := runtime.GOOS
+	switch os {
+	case "darwin":
+		protoCGenGoFilename = filepath.Join(goPath, "bin", "protoc-gen-go")
+	case "windows":
+		protoCGenGoFilename = filepath.Join(goPath, "bin", "protoc-gen-go.exe")
+	default:
+		return nil, fmt.Errorf("unexpeted os: %s", os)
+	}
+
+	if !util.FileExists(protoCGenGoFilename) {
+		sh := "go install " + filepath.Join(protobuf, constProtoCGenGo)
+		log.Warning(sh)
+		stdout, err := execx.Run(sh)
+		if err != nil {
+			return nil, err
+		}
+
+		log.Info(stdout)
+	}
+	if !util.FileExists(protoCGenGoFilename) {
+		return nil, fmt.Errorf("protoc-gen-go is not found")
+	}
+	return &Project{
+		Name:   name,
+		Path:   path,
+		GoPath: goPath,
+		Protobuf: Protobuf{
+			Path: protobuf,
+		},
+		GoMod: GoMod{
+			ModOn:      goModOn,
+			GoModCache: goModCache,
+			GoMod:      goMod,
+			Module:     module,
+		},
+	}, nil
+}
+
+// github.com/golang/protobuf@{version}
+func matchProtoBuf(data []byte) (string, error) {
+	text := string(data)
+	re := regexp.MustCompile(`(?m)(github.com/golang/protobuf)\s+(v[0-9.]+)`)
+	matches := re.FindAllStringSubmatch(text, -1)
+	if len(matches) == 0 {
+		return "", errProtobufNotFound
+	}
+	groups := matches[0]
+	if len(groups) < 3 {
+		return "", errProtobufNotFound
+	}
+	return fmt.Sprintf("%s@%s", groups[1], groups[2]), nil
+}
+
+func matchModule(data []byte) (string, error) {
+	text := string(data)
+	re := regexp.MustCompile(`(?m)^\s*module\s+[a-z0-9/\-.]+$`)
+	matches := re.FindAllString(text, -1)
+	if len(matches) == 1 {
+		target := matches[0]
+		index := strings.Index(target, "module")
+		return strings.TrimSpace(target[index+6:]), nil
+	}
+	return "", nil
+}