gk

Go-Kit 生成器

Go-kit 生成器是一个命令行应用程序，可根据参数生成go-kit service模板代码

Why?

**Because I'm lazy**, and because it would make it easier for go-kit newcomers to start using it.

上面是原作者开发这个程序的原因，对于我：

• 这样一个可方便生成go-kit代码的程序，不但可以减少手敲代码的数量，还可以预防很多错误
• 原项目在我fork的时候已经很长时间没有更新功能了，由于go-kit addsvc调整了代码布局，我急需一个可以生成与go-kit官方代码布局相同的生成器

安装

go get github.com/yiv/gk
go install github.com/yiv/gk

运行

gk必须要在$GOPATH目录及其任何子目录下才能运行，不一定要$GOPATH根目录，你可以在$GOPATH路径下创建一个工程目录，然后在该目录运行。

gk首次运行的时候会在运行目录查找gk.json配置文件，如果未找到，它会根据默认配置生成新的gk.json文件

创建新 service

在工程目录下运行:

gk new service hello

或使用短命令:

gk n s hello

运行本命令会生成一个 helloservice :

./
└── hello
    └── pkg
        └── helloservice
            └── service.go

service.go

package service
// Implement yor service methods methods.
// e.x: Foo(ctx context.Context,s string)(rs string,err error)
type Service interface {
}

Now you need to add the interface methods and initiate your service: e.x:

package helloservice

// Implement yor service methods methods.
// e.x: Foo(ctx context.Context,bar string)(rs string, err error)
type Service interface {
}

然后运行 :

gk init hello

运行这个命令后会新增如下代码文件

.
└── hello
    └── pkg
        ├── helloendpoint
        │   ├── middleware.go
        │   └── set.go
        ├── helloservice
        │   ├── instrumenting.go
        │   ├── logging.go
        │   └── service.go
        └── hellotransport
            └── http.go

By Default the generator will use default_transport setting from gk.json and create the transport. If you want to specify the transport use -t flag

gk init hello -t grpc

添加其它 transports

在现在工程里添加其它 transports 运行 gk add [transporteType] [serviceName]
e.x adding grpc:

gk add grpc hello

运行上面的命令后，你会在控制台看到如下打印信息：

INFO[0000] Generating grpc transport...                 
WARN[0000] -------------------------------------------------------------------- 
WARN[0000] The service is still not ready!!             
WARN[0000] To create the grpc transport please create your protobuf. 
WARN[0000] Than follow the instructions in compile.sh and compile the .proto file. 
WARN[0000] After the file is compiled run `gk init grpc hello`. 
WARN[0000] -------------------------------------------------------------------- 

此时的代码目录结构是这样的：

.
└── hello
    ├── pb
    │   ├── compile.bat
    │   └── hello.proto
    └── pkg
        ├── helloendpoint
        │   ├── middleware.go
        │   └── set.go
        ├── helloservice
        │   ├── instrumenting.go
        │   ├── logging.go
        │   └── service.go
        └── hellotransport
            └── http.go

完成 grpc transport的添加，你需要先编译 protobuffer 文件，然后再运行下面的命令

gk init grpc hello

最终生成的代码结构跟go-kit的官方示例addsvc 相同，不同之外在于我将service的middleware.go文件拆分成了两个文件，分别是instrumenting.go和logging.go 下面是完成后的目录结果

.
└── hello
    ├── pb
    │   ├── compile.bat
    │   ├── hello.pb.go
    │   └── hello.proto
    └── pkg
        ├── helloendpoint
        │   ├── middleware.go
        │   └── set.go
        ├── helloservice
        │   ├── instrumenting.go
        │   ├── logging.go
        │   └── service.go
        └── hellotransport
            ├── grpc.go
            └── http.go

下面是原项目的代码布局：

project/
└── pkg
    ├── endpoints
    │   └── endpoints.go
    ├── grpc
    │   ├── handler.go
    │   └── pb
    │       ├── compile.bat
    │       ├── hello.pb.go
    │       └── hello.proto
    ├── http
    │   └── handler.go
    └── service
        └── service.go

I don't like the folder structure!

The folder structure that the generator is using is following https://github.com/go-kit/kit/issues/70 but that can be changed using gk.json all the paths are configurable there.

Cli Help

Every command has the -h or --help flag this will give you more info on what the command does and how to use it. e.x

gk init -h

will return

Initiates a service

Usage:
  gk init [flags]

Flags:
  -t, --transport string   Specify the transport you want to initiate for the service

Global Flags:
  -d, --debug           If you want to se the debug logs.
      --folder string   If you want to specify the base folder of the project.
  -f, --force           Force overide existing files without asking.
      --testing         If testing the generator.

What is working

The example you see here https://github.com/go-kit/kit/issues/70

Examples

You can find examples under the test_dir

TODO-s

• Implement the update commands, this commands would be used to update an existing service e.x add a new request parameter to an endpoint(Probably not needed).
• Implement automatic creation of the service main file.
• Tests tests tests ...

Warnings

• I only tested this on the mac, should work on other os-s but I have not tested it, I would appreciate feedback on this.

Contribute

Thanks a lot for contributing.

To test your new features/bug-fixes you need a way to run gk inside your project this can be done using test_dir.

Execute this in your command line :

export GK_FOLDER="test_dir" 

Create a folder in the gk repository called test_dir, now every time you run go run main.go [anything] gk will treat test_dir as the project root.

If you edit the templates you need to run compile.sh inside the templates folder.