greeter/

README

Greeter Service

An example Go service running with go-micro

What's here?

• Server - an RPC greeter service
• Client - an RPC client that calls the service once
• Api - examples of RPC API and RESTful API
• Web - how to use go-web to write web services

Prerequisites

Service discovery is required either running Consul as the default or MDNS for zero dependencies. You can also use plugins from micro/plugins.

MDNS

To use MDNS just add the flag --registry=mdns on the command line.

Consul

Install Consul https://www.consul.io/intro/getting-started/install.html

Run Consul

$ consul agent -dev -advertise=127.0.0.1

Run Service

Start go.micro.srv.greeter

$ go run server/main.go
I0523 12:27:56.685569   90096 server.go:113] Starting server go.micro.srv.greeter id go.micro.srv.greeter-c2770c77-013e-11e5-b4d6-68a86d0d36b6
I0523 12:27:56.685890   90096 rpc_server.go:112] Listening on [::]:52019
I0523 12:27:56.685931   90096 server.go:95] Registering node: go.micro.srv.greeter-c2770c77-013e-11e5-b4d6-68a86d0d36b6

Client

Call go.micro.srv.greeter via client

$ go run client/client.go
go.micro.srv.greeter-c2770c77-013e-11e5-b4d6-68a86d0d36b6: Hello John

Examples of client usage via other languages can be found in the client directory.

API

HTTP based requests can be made via the micro API. Micro logically separates API services from backend services. By default the micro API accepts HTTP requests and converts to *api.Request and *api.Response types. Find them here micro/api/proto.

Run the go.micro.api.greeter API Service

$ go run api/api.go 
I0523 12:27:25.475548   89125 server.go:113] Starting server go.micro.api.greeter id go.micro.api.greeter-afdcc369-013e-11e5-8710-68a86d0d36b6
I0523 12:27:25.475890   89125 rpc_server.go:112] Listening on [::]:51997
I0523 12:27:25.475927   89125 server.go:95] Registering node: go.micro.api.greeter-afdcc369-013e-11e5-8710-68a86d0d36b6

Run the micro API

$ micro api
I0523 12:23:23.413940   81384 api.go:131] API Rpc handler /rpc
I0523 12:23:23.414238   81384 api.go:143] Listening on [::]:8080
I0523 12:23:23.414272   81384 server.go:113] Starting server go.micro.api id go.micro.api-1f951765-013e-11e5-9273-68a86d0d36b6
I0523 12:23:23.414355   81384 rpc_server.go:112] Listening on [::]:51938
I0523 12:23:23.414399   81384 server.go:95] Registering node: go.micro.api-1f951765-013e-11e5-9273-68a86d0d36b6

Call go.micro.api.greeter via API

curl http://localhost:8080/greeter/say/hello?name=John
{"message":"Hello John"}

Examples of other API handlers can be found in the API directory.

Sidecar

The sidecar is a language agnostic RPC proxy.

Run the micro sidecar

$ micro sidecar
2016/12/01 14:26:44 Registering Root Handler at /
2016/12/01 14:26:44 Registering Registry handler at /registry
2016/12/01 14:26:44 Registering RPC handler at /rpc
2016/12/01 14:26:44 Registering Broker handler at /broker
2016/12/01 14:26:44 Listening on [::]:8081
2016/12/01 14:26:44 Listening on [::]:51287
2016/12/01 14:26:44 Broker Listening on [::]:51288
2016/12/01 14:26:44 Registering node: go.micro.sidecar-2f727f0c-b7d2-11e6-aa3b-68a86d0d36b6

Call go.micro.srv.greeter via sidecar

curl -H 'Content-Type: application/json' -d '{"name": "john"}' http://localhost:8081/greeter/say/hello
{"msg":"Hello john"}

The sidecar provides all the features of go-micro as a HTTP API. Learn more at micro/car.

Web

The micro web is a web dashboard and reverse proxy to run web apps as microservices.

Run go.micro.web.greeter

$ go run web/web.go 
Listening on [::]:51348

Run the micro web

$ micro web
2016/12/01 14:30:22 Listening on [::]:8082
2016/12/01 14:30:22 Listening on [::]:51334
2016/12/01 14:30:22 Broker Listening on [::]:51335
2016/12/01 14:30:22 Registering node: go.micro.web-b10c7e52-b7d2-11e6-a39c-68a86d0d36b6

Browse to http://localhost:8082/greeter