go-micro/examples/event/README.md

Event

This is an example of using the micro API as an event gateway with the event handler

A http request is formatted as an event and published on the go-micro message broker.

Contents

• srv - A service which subscribes to events

Usage

Run the micro api with the event handler set and with a namespace which used as part of the topic name

micro api --handler=event --namespace=go.micro.evt

Run the service

go run srv/main.go

Event format

On the receiving end the message will be formatted like so:

// A HTTP event as RPC
message Event {
	// e.g login
	string name = 1;
	// uuid
	string id = 2;
	// unix timestamp of event
	int64 timestamp = 3;
	// event headers
        map<string, Pair> header = 4;
	// the event data
	string data = 5;
}

Publish Event

Publishing an event is as simple as making a http post request

curl -d '{"name": "john"}' http://localhost:8080/user/login

This request will be published to the topic go.micro.evt.user with event name login

Receiving Event

A subscriber should be registered with the service for topic go.micro.evt.user

The subscriber should take the proto.Event type. See srv/main.go for the code.

The event received will look like the following

{
	name: "user.login",
	id: "go.micro.evt.user-user.login-693116e7-f20c-11e7-96c7-f40f242f6897",
	timestamp:1515152077,
	header: {...},
	data: {"name": "john"} 
}