Support gRPC Web plugin install

README.md

@@ -11,9 +11,10 @@ Downloads and unpacks Protocol Buffers compiler protoc.
 
 ## To run
 ### Arguments
-* -ver: Protocol Buffers compiler version
+* -type: "cli" for protoc or "grpc-web" for gRPC Web protoc plugin
+* -ver: version to install
 * -out: output directory
 ### Example
 ```shell
-    protoc-install -ver 3.10.1 -out bin
+    protoc-install -type cli -ver 3.10.1 -out bin
 ```

main.go

@@ -12,7 +12,9 @@ import (
 )
 
 var (
-	version = flag.String("ver", "", "protoc version, for ex. 3.10.1")
+	protocType = flag.String("type", "protoc",
+		`type, "cli" for protoc or "grpc-web" for gRPC Web protoc plugin`)
+	version = flag.String("ver", "", "version to install, for ex. 3.10.1")
 	outDir  = flag.String("out", "", "output directory")
 )
 
@@ -22,48 +24,72 @@ func main() {
 		log.Fatal("Version is not set.\n")
 	}
 	if len(*outDir) == 0 {
-		log.Fatal("Destination is not set.\n")
+		log.Fatal("Out is not set.\n")
 	}
-
-	binFilePath := filepath.Join(*outDir, binFile)
-	if _, err := os.Stat(binFilePath); !os.IsNotExist(err) {
-		log.Printf("protoc is already existing (\"%s\").\n", binFilePath)
+	if *protocType == "cli" {
+		installProtoc()
 		return
 	}
+	if *protocType == "grpc-web" {
+		installGRPCWebPlugin()
+		return
+	}
+	log.Fatal("Unknown type.\n")
+}
 
-	archFile := fmt.Sprintf("protoc-%s-%s.zip", *version, platform)
-	archFilePath := filepath.Join(*outDir, archFile)
-	if _, err := os.Stat(binFilePath); os.IsNotExist(err) {
+func download(source, file string) string {
+	path := filepath.Join(*outDir, file)
+	if _, err := os.Stat(path); !os.IsNotExist(err) {
+		return path
+	}
 
-		url := fmt.Sprintf("https://github.com/protocolbuffers/protobuf/releases/download/v%s/%s", *version, archFile)
-		log.Printf("Downloading protoc archive from \"%s\"...\n", url)
+	log.Printf("Downloading from \"%s\"...\n", source)
 
-		if err = os.MkdirAll(filepath.Dir(archFilePath), os.ModePerm); err != nil {
-			panic(err)
-		}
+	err := os.MkdirAll(filepath.Dir(path), os.ModePerm)
+	if err != nil {
+		panic(err)
+	}
 
-		resp, err := http.Get(url)
-		if err != nil {
-			panic(err)
-		}
-		defer resp.Body.Close()
+	response, err := http.Get(source)
+	if err != nil {
+		panic(err)
+	}
+	defer response.Body.Close()
 
-		out, err := os.Create(archFilePath)
-		if err != nil {
-			panic(err)
-		}
-		defer func() {
-			out.Close()
-			if err := os.Remove(archFilePath); err != nil {
-				log.Printf("Failed to remove archive file: \"%s\".", err)
-			}
-		}()
-
-		_, err = io.Copy(out, resp.Body)
-		if err != nil {
-			panic(err)
-		}
+	out, err := os.Create(path)
+	if err != nil {
+		panic(err)
 	}
+	defer out.Close()
+
+	_, err = io.Copy(out, response.Body)
+	if err != nil {
+		panic(err)
+	}
+
+	return path
+}
+
+func remove(path string) {
+	if err := os.Remove(path); err != nil {
+		log.Printf("Failed to remove \"%s\": \"%s\".", path, err)
+	}
+}
+
+func installProtoc() {
+
+	binFilePath := filepath.Join(*outDir, protocFile)
+	if _, err := os.Stat(binFilePath); !os.IsNotExist(err) {
+		log.Printf("protoc is already existing (\"%s\").\n", binFilePath)
+		return
+	}
+
+	archFile := fmt.Sprintf("protoc-%s-%s.zip", *version, protocPlatform)
+	url := fmt.Sprintf(
+		"https://github.com/protocolbuffers/protobuf/releases/download/v%s/%s",
+		*version, archFile)
+	archFilePath := download(url, archFile)
+	defer remove(archFilePath)
 
 	log.Printf("Unpacking into \"%s\"...\n", binFilePath)
 	arch, err := zip.OpenReader(archFilePath)
@@ -72,7 +98,7 @@ func main() {
 	}
 	defer arch.Close()
 
-	binInsideArchPath := "bin/" + binFile
+	binInsideArchPath := "bin/" + protocFile
 	for _, file := range arch.File {
 		if file.Name != binInsideArchPath {
 			continue
@@ -81,7 +107,6 @@ func main() {
 		if err != nil {
 			panic(err)
 		}
-		defer bin.Close()
 		r, err := file.Open()
 		if err != nil {
 			panic(err)
@@ -91,9 +116,27 @@ func main() {
 		if err != nil {
 			panic(err)
 		}
-		log.Println("Successfully installed.")
+		bin.Close()
+		err = os.Chmod(binFilePath, 0777)
+		if err != nil {
+			panic(err)
+		}
+		log.Println("protoc successfully installed.")
 		return
 	}
 
 	log.Fatalf("Archive \"%s\" does not have protoc.\n", archFilePath)
 }
+
+func installGRPCWebPlugin() {
+	fileName := "protoc-gen-grpc-web"
+	url := fmt.Sprintf(
+		"https://github.com/grpc/grpc-web/releases/download/%s/%s-%s-%s%s",
+		*version, fileName, *version, grpcWebPlatform, grpcWebFileExt)
+	binFilePath := download(url, fileName+grpcWebFileExt)
+	err := os.Chmod(binFilePath, 0777)
+	if err != nil {
+		panic(err)
+	}
+	log.Println("gRPC Web protoc plugin installed.")
+}

platform_unix.go

@@ -3,6 +3,9 @@
 package main
 
 const (
-	platform = "linux-x86_64"
-	binFile  = "protoc"
+	protocPlatform = "linux-x86_64"
+	protocFile     = "protoc"
+
+	grpcWebPlatform = "linux-x86_64"
+	grpcWebFileExt  = ""
 )

platform_windows.go

@@ -3,6 +3,9 @@
 package main
 
 const (
-	platform = "win64"
-	binFile  = "protoc.exe"
+	protocPlatform = "win64"
+	protocFile     = "protoc.exe"
+
+	grpcWebPlatform = "windows-x86_64"
+	grpcWebFileExt  = ".exe"
 )