plugin

README

Plugins

Go plugins is a place for community maintained plugins.

Overview

Micro tooling is built on a powerful pluggable architecture. Plugins can be swapped out with zero code changes. This repository contains plugins for all micro related tools. Read on for further info.

Getting Started

• Contents
• Usage
• Build Pattern
• Contributions

Contents

Contents of this repository:

Directory	Description
Broker	PubSub messaging; NATS, NSQ, RabbitMQ, Kafka
Client	RPC Clients; gRPC, HTTP
Codec	Message Encoding; BSON, Mercury
Micro	Micro Toolkit Plugins
Registry	Service Discovery; Etcd, Gossip, NATS
Selector	Load balancing; Label, Cache, Static
Server	RPC Servers; gRPC, HTTP
Transport	Bidirectional Streaming; NATS, RabbitMQ
Wrapper	Middleware; Circuit Breakers, Rate Limiting, Tracing, Monitoring

Usage

Plugins can be added to go-micro in the following ways. By doing so they'll be available to set via command line args or environment variables.

Import the plugins in a plugins.go file

package main

import (
	_ "github.com/geiqin/go-plugins/broker/rabbitmq/v2"
	_ "github.com/geiqin/go-plugins/registry/kubernetes/v2"
	_ "github.com/geiqin/go-plugins/transport/nats/v2"
)

Create your service and ensure you call service.Init

package main

import (
	"github.com/geiqin/go-micro"
)

func main() {
	service := micro.NewService(
		// Set service name
		micro.Name("my.service"),
	)

	// Parse CLI flags
	service.Init()
}

Build your service

go build -o service ./main.go ./plugins.go

Env

Use environment variables to set the

MICRO_BROKER=rabbitmq \
MICRO_REGISTRY=kubernetes \ 
MICRO_TRANSPORT=nats \ 
./service

Flags

Or use command line flags to enable them

./service --broker=rabbitmq --registry=kubernetes --transport=nats

Options

Import and set as options when creating a new service

import (
	"github.com/geiqin/go-micro"
	"github.com/geiqin/go-plugins/registry/kubernetes/v2"
)

func main() {
	registry := kubernetes.NewRegistry() //a default to using env vars for master API

	service := micro.NewService(
		// Set service name
		micro.Name("my.service"),
		// Set service registry
		micro.Registry(registry),
	)
}

Build

An anti-pattern is modifying the main.go file to include plugins. Best practice recommendation is to include plugins in a separate file and rebuild with it included. This allows for automation of building plugins and clean separation of concerns.

Create file plugins.go

package main

import (
	_ "github.com/geiqin/go-plugins/broker/rabbitmq/v2"
	_ "github.com/geiqin/go-plugins/registry/kubernetes/v2"
	_ "github.com/geiqin/go-plugins/transport/nats/v2"
)

Build with plugins.go

go build -o service main.go plugins.go

Run with plugins

MICRO_BROKER=rabbitmq \
MICRO_REGISTRY=kubernetes \
MICRO_TRANSPORT=nats \
service

Documentation

Overview

Package plugin provides the ability to load plugins

Index

• func Build(path string, p *Plugin) error
• func Generate(path string, p *Plugin) error
• func Init(p *Plugin) error
• type Plugin
  • func Load(path string) (*Plugin, error)

Functions

func Build

func Build(path string, p *Plugin) error

Build generates a dso plugin using the go command `go build -buildmode=plugin`

func Generate

func Generate(path string, p *Plugin) error

Generate creates a go file at the specified path. You must use `go build -buildmode=plugin`to build it.

func Init

func Init(p *Plugin) error

Init sets up the plugin

Types

type Plugin

type Plugin struct {
	// Name of the plugin e.g rabbitmq
	Name string
	// Type of the plugin e.g broker
	Type string
	// Path specifies the import path
	Path string
	// NewFunc creates an instance of the plugin
	NewFunc interface{}
}

Plugin is a plugin loaded from a file

func Load

func Load(path string) (*Plugin, error)

Load loads a plugin created with `go build -buildmode=plugin`