Ably Go

A Go client library for www.ably.io, the realtime messaging service.

Installation

~ $ go get -u github.com/ably/ably-go/ably

Using the Realtime API

Creating a client

client, err := ably.NewRealtimeClient(ably.NewClientOptions("xxx:xxx"))
if err != nil {
	panic(err)
}

channel := client.Channels.Get("test")

Subscribing to a channel for all events

sub, err := channel.Subscribe()
if err != nil {
	panic(err)
}

for msg := range sub.MessageChannel() {
	fmt.Println("Received message:", msg)
}

Subscribing to a channel for EventName1 and EventName2 events

sub, err := channel.Subscribe("EventName1", "EventName2")
if err != nil {
	panic(err)
}

for msg := range sub.MessageChannel() {
	fmt.Println("Received message:", msg)
}

Publishing to a channel

// send request to a server
res, err := channel.Publish("EventName1", "EventData1")
if err != nil {
	panic(err)
}

// await confirmation
if err = res.Wait(); err != nil {
	panic(err)
}

Announcing presence on a channel

// send request to a server
res, err := channel.Presence.Enter("presence data")
if err != nil {
	panic(err)
}

// await confirmation
if err = res.Wait(); err != nil {
	panic(err)
}

Announcing presence on a channel on behalf of other client

// send request to a server
res, err := channel.Presence.EnterClient("clientID", "presence data")
if err != nil {
	panic(err)
}

// await confirmation
if err = res.Wait(); err != nil {
	panic(err)
}

Getting all clients present on a channel

clients, err := channel.Presence.Get(true)
if err != nil {
	panic(err)
}

for _, client := range clients {
	fmt.Println("Present client:", client)
}

Subscribing to all presence messages

sub, err := channel.Presence.Subscribe()
if err != nil {
	panic(err)
}

for msg := range sub.PresenceChannel() {
	fmt.Println("Presence event:", msg)
}

Subscribing to 'Enter' presence messages only

sub, err := channel.Presence.Subscribe(proto.PresenceEnter)
if err != nil {
	panic(err)
}

for msg := range sub.PresenceChannel() {
	fmt.Println("Presence event:", msg)
}

Using the REST API

Introduction

All examples assume a client and/or channel has been created as follows:

client, err := ably.NewRestClient(ably.NewClientOptions("xxx:xxx"))
if err != nil {
	panic(err)
}

channel := client.Channels.Get("test")

Publishing a message to a channel

err = channel.Publish("HelloEvent", "Hello!")
if err != nil {
	panic(err)
}

Querying the History

page, err := channel.History(nil)
for ; err == nil; page, err = page.Next() {
	for _, message := range page.Messages() {
		fmt.Println(message)
	}
}
if err != nil {
	panic(err)
}

Presence on a channel

page, err := channel.Presence.Get(nil)
for ; err == nil; page, err = page.Next() {
	for _, presence := range page.PresenceMessages() {
		fmt.Println(presence)
	}
}
if err != nil {
	panic(err)
}

Querying the Presence History

page, err := channel.Presence.History(nil)
for ; err == nil; page, err = page.Next() {
	for _, presence := range page.PresenceMessages() {
		fmt.Println(presence)
	}
}
if err != nil {
	panic(err)
}

Generate Token and Token Request

client.Auth.RequestToken()
client.Auth.CreateTokenRequest()

Fetching your application's stats

page, err := client.Stats(&ably.PaginateParams{})
for ; err == nil; page, err = page.Next() {
	for _, stat := range page.Stats() {
		fmt.Println(stat)
	}
}
if err != nil {
	panic(err)
}

Known limitations (work in progress)

As the library is actively developed couple of features are not there yet:

• Realtime connection recovery is not implemented
• Realtime connection failure handling is not implemented
• ChannelsOptions and CipherParams are not supported when creating a Channel
• Realtime Ping function is not implemented

Release process

This library uses semantic versioning. For each release, the following needs to be done:

• Create a branch for the release, named like release-1.0.6
• Replace all references of the current version number with the new version number and commit the changes
• Run github_changelog_generator to update the CHANGELOG: github_changelog_generator -u ably -p ably-go --header-label="# Changelog" --release-branch=release-1.0.6 --future-release=v1.0.6
• Commit CHANGELOG
• Add a tag and push to origin such as git tag v1.0.6; git push origin v1.0.6
• Make a PR against develop
• Once the PR is approved, merge it into develop
• Fast-forward the master branch: git checkout master && git merge --ff-only develop && git push origin master

Support and feedback

Please visit http://support.ably.io/ for access to our knowledgebase and to ask for any assistance.

You can also view the community reported Github issues.

Contributing

Because this package uses internal packages, all fork development has to happen under $GOPATH/src/github.com/ably/ably-go to prevent use of internal package not allowed errors.

1. Fork github.com/ably/ably-go
2. go to the ably-go directory: cd $GOPATH/src/github.com/ably/ably-go
3. add your fork as a remote: git remote add fork [email protected]:your-username/ably-go
4. create your feature branch: git checkout -b my-new-feature
5. commit your changes (git commit -am 'Add some feature')
6. ensure you have added suitable tests and the test suite is passing: make test
7. push to the branch: git push fork my-new-feature
8. create a new Pull Request

License

Copyright (c) 2016 Ably Real-time Ltd, Licensed under the Apache License, Version 2.0. Refer to LICENSE for the license terms.