grpc-gateway-generator

A script to generate a ready to use grpc-gateway, with swagger, by just providing the protos and a simple configuration file.

Status: Alpha, it's not production ready yet. See TODO list below.

Installation

Prerequisites

• If you don't have go installed, install go
• Install grpc-gateway dependencies. (ProtocolBuffers 3.0.0-beta-3 or later), and the following packages:

go get -u google.golang.org/grpc
go get -u github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway
go get -u github.com/grpc-ecosystem/grpc-gateway/protoc-gen-swagger
go get -u github.com/golang/protobuf/protoc-gen-go

• Install the script dependencies:

  • jq

Clone

git clone https://github.com/devsu/grpc-gateway-generator

Usage

./generate.sh protos-path config-file project-path  

Arguments

• protos-path: The path to the protos folder.

  The package names of the protos files must correspond to the folder structure. For example:

  • /protos/myapp/my-file.proto must have the package myapp, and
  • /protos/myapp/mymicroservice/another-file.proto must have the package myapp.mymicroservice

• config-file: Path to a config.json file. The config file has two sections: gateway and backends.

  In the gateway section, you define the address that the gateway will listen into.

  The backends is an array of objects with 3 properties:

  • package: name of the package.
  • backend: what addres the GRPC server is running.
  • services: An object with the services names as keys, and the base paths of the services as values.

  See config.json for an example of how it should look:

  {
   "gateway": {
     "listen": ":9090"
   },
   "backends": [
     {
       "package": "myapp",
       "backend": "localhost:3000",
       "services": {
         "GreeterService": "/sample/greeter/"
       }
     },
     {
       "package": "myapp.mysubapp",
       "backend": "localhost:3000",
       "services": {
         "AnotherGreeterService": "/sample/another-greeter/"
       }
     }
   ]
  }

• project-path: The path of the go project to be created. The gateway will be created in ${GOPATH}/src/${projectPath}. Read How to write Go Code to learn how to choose a proper project path.

Step by step guide

• First, create your protos and add the corresponding annotations. You can see the grpc-gateway documentation or the sample file in examples/protos/myapp for an example.

• Then you need to create a config file. (See instructions above)

• Then you just need to run the command with the right arguments.

  For example, to create a grpc-gateway using the information in the example:

  ./generate.sh example/protos example/config.json github.com/my-user/my-gateway

TODO

• Support TLS in both, the gateway, and the backends
• Make swagger creation optional
• Test on more OSs, currently only tested on Mac an Alpine
• Clean up the script
• Allow to configure authorization (currently it activates bearer authorization by default)
• Upgrade swagger-ui?

License and Credits

Devsu LLC. MIT License. Copyright 2017.

Built by the GRPC experts at Devsu.