cloud

Documentation

Overview

Package cloud implements an events.PubSub implementation that uses Go Cloud PubSub.

Example

package main

import (
	"context"

	"go.thethings.network/lorawan-stack/v3/pkg/component"
	"go.thethings.network/lorawan-stack/v3/pkg/events"
	"go.thethings.network/lorawan-stack/v3/pkg/events/cloud"

	_ "gocloud.dev/pubsub/mempubsub"
)

func main() {
	// The task starter is used for automatic re-subscription on failure.
	taskStarter := component.StartTaskFunc(component.DefaultStartTask)

	// Import the desired cloud pub-sub drivers (see godoc.org/gocloud.dev).
	// In this example we use "gocloud.dev/pubsub/mempubsub".

	// This sends all events received from a Go Cloud pub sub to the default pubsub.
	cloudPubSub, err := cloud.WrapPubSub(context.TODO(), events.DefaultPubSub(), taskStarter, "mem://events", "mem://events")
	if err != nil {
		// Handle error.
	}

	// Replace the default pubsub so that we will now publish to a Go Cloud pub sub.
	events.SetDefaultPubSub(cloudPubSub)
}

Index

• type PubSub
  • func NewPubSub(ctx context.Context, taskStarter component.TaskStarter, pubURL, subURL string) (*PubSub, error)
  • func WrapPubSub(ctx context.Context, wrapped events.PubSub, taskStarter component.TaskStarter, ...) (ps *PubSub, err error)
  • func (ps *PubSub) Close(ctx context.Context) error
  • func (ps *PubSub) Publish(evt events.Event)
  • func (ps *PubSub) Subscribe(name string, hdl events.Handler) error

Examples

• Package

Types

type PubSub

type PubSub struct {
	events.PubSub
	// contains filtered or unexported fields
}

PubSub with Go Cloud backend.

func NewPubSub

func NewPubSub(ctx context.Context, taskStarter component.TaskStarter, pubURL, subURL string) (*PubSub, error)

NewPubSub creates a new PubSub that publishes and subscribes to Go Cloud. If the subURL is an empty string, this PubSub will only publish to Go Cloud.

func WrapPubSub

func WrapPubSub(ctx context.Context, wrapped events.PubSub, taskStarter component.TaskStarter, pubURL, subURL string) (ps *PubSub, err error)

WrapPubSub wraps an existing PubSub and publishes all events received from Go Cloud to that PubSub. If the subURL is an empty string, this PubSub will only publish to Go Cloud.

func (*PubSub) Close

func (ps *PubSub) Close(ctx context.Context) error

Close the Go Cloud publisher.

func (*PubSub) Publish

func (ps *PubSub) Publish(evt events.Event)

Publish an event to Go Cloud.

func (*PubSub) Subscribe

func (ps *PubSub) Subscribe(name string, hdl events.Handler) error

Subscribe to events from Go Cloud.