Presence API for Ruby SDK

Presence enables you to track the online and offline status of users and devices in real time and store custom state information. Presence provides authoritative information on:

When a user has joined or left a channel
Who, and how many, users are subscribed to a particular channel
Which channel(s) an individual user is subscribed to
Associated state information for these users

Learn more about our Presence feature here.

Here Now

Requires Presence

This method requires that the Presence add-on is enabled for your key in the Admin Portal.

For information on how to receive presence events and what those events are, refer to Presence Events.

You can obtain information about the current state of a channel including a list of unique user-ids currently subscribed to the channel and the total occupancy count of the channel by calling the here_now() function in your application.

Cache

This method has a 3 second response cache time.

Method(s)

To call Here Now you can use the following method(s) in the Ruby SDK:

here_now(
    channels: channels,
    channel_groups: channel_groups,
    http_sync: http_sync,
    callback: callback
)

* required

Parameter	Description
`channels` Type: String, Symbol	Specify the `channels` name to return occupancy results. If `channels` is not provided, `here_now` will return data for all channels (global `here_now`).
`channel_groups` Type: String, Symbol	Specify the `channel_groups` name to return occupancy results.
`http_sync` Type: Boolean	Default `false`. Method will be executed `asynchronously` and will return future, to get it's `value` you can use `value` method. If set to `true`, method will return array of envelopes (even if there's only one `envelope`). For `sync` methods `Envelope` object will be returned.
`callback` Type: Lambda accepting one parameter	`Callback` that will be called for each `envelope`. For `async` methods future will be returned, to retrieve `value` `Envelope` object you have to call `value` method (thread will be locked until the `value` is returned).

Basic Usage

Get a list of uuids subscribed to channel

Reference code

This example is a self-contained code snippet ready to be run. It includes necessary imports and executes methods with console logging. Use it as a reference when working with other examples in this document.

require 'pubnub'

def fetch_uuids(pubnub)
  pubnub.here_now(
    channel: 'my_channel'
  ) do |envelope|
    if envelope.status[:error]
      puts "Error fetching UUIDs: #{envelope.status[:error]}"
    else
      puts "UUIDs subscribed to my_channel: #{envelope.result[:data][:uuids]}"
      puts "Occupancy: #{envelope.result[:data][:occupancy]}"
    end
  end
end

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Response

#<Pubnub::Envelope
    @result = {
        :data => {
            :uuids => ["2d588b75-0451-4bde-8952-13128c10e952"],
            :occupancy => 1
        }
    },
    @status = {
        :code => 200
    }
>

Where Now

Requires Presence

This method requires that the Presence add-on is enabled for your key in the Admin Portal.

For information on how to receive presence events and what those events are, refer to Presence Events.

You can obtain information about the current list of channels to which a UUID is subscribed to by calling the where_now() function in your application.

Timeout events

If the app is killed/crashes and restarted (or the page containing the PubNub instance is refreshed on the browser) within the heartbeat window no timeout event is generated.

Method(s)

To call where_now() you can use the following method(s) in the Ruby SDK:

where_now(
    uuid: uuid,
    http_sync: http_sync,
    callback: callback
)

* required

Parameter	Description
`uuid` * Type: String	`UUID` we are looking for.
`http_sync` Type: Boolean	Default `false`. Method will be executed `asynchronously` and will return future, to get it's `value` you can use `value` method. If set to `true`, method will return array of envelopes (even if there's only one `envelope`). For `sync` methods `Envelope` object will be returned.
`callback` Type: Lambda accepting one parameter	`Callback` that will be called for each `envelope`. For `async` methods future will be returned, to retrieve `value` `Envelope` object you have to call `value` method (thread will be locked until the `value` is returned).

Basic Usage

You simply need to define the uuid and the callback function to be used to send the data to as in the example below.

Get a list of channels a UUID is subscribed to

pubnub.where_now(
    uuid: "my_uuid"
) do |envelope|
    puts envelope.result[:data]
end

Response

#<Pubnub::Envelope:0x007fd38584c168
    @result = {
        :data => {
        "channels" => ["whatever"]
        }
    },
    @status = {
        :code =>200
    }
>

User State

Requires Presence

This method requires that the Presence add-on is enabled for your key in the Admin Portal.

For information on how to receive presence events and what those events are, refer to Presence Events.

Clients can set a dynamic custom state (score, game state, location) for their users on one or more channels and store it on a channel as long as the user stays subscribed.

The state is not persisted, and when the client disconnects, the state data is lost. For more information, refer to Presence State.

Method(s)

set_state(
    channels: channels,
    state: state,
    http_sync: http_sync,
    callback: callback
)

* required

Parameter	Description
`channels` * Type: String, Symbol	Specify `channels` name to set `state` for.
`state` * Type: Hash	The `state` to set.
`http_sync` Type: Boolean	Default `false`. Method will be executed `asynchronously` and will return future, to get it's `value` you can use `value` method. If set to `true`, method will return array of envelopes (even if there's only one `envelope`). For `sync` methods `Envelope` object will be returned.
`callback` Type: Lambda accepting one parameter	`Callback` that will be called for each `envelope`. For `async` methods future will be returned, to retrieve `value` `Envelope` object you have to call `value` method (thread will be locked until the `value` is returned).

get_state(
    channels: channels,
    uuid: uuid,
    http_sync: http_sync,
    callback: callback
)

* required

Parameter	Description
`channels` * Type: String, Symbol	Specify `channels` name to get `state` from.
`uuid` Type: String	Specifies `UUID`.
`http_sync` Type: Boolean	Default `false`. Method will be executed `asynchronously` and will return future, to get it's `value` you can use `value` method. If set to `true`, method will return array of envelopes (even if there's only one `envelope`). For `sync` methods `Envelope` object will be returned.
`callback` Type: Lambda accepting one parameter	`Callback` that will be called for each `envelope`. For `async` methods future will be returned, to retrieve `value` `Envelope` object you have to call `value` method (thread will be locked until the `value` is returned).

Basic Usage

Set State

pubnub.set_state(channel: 'my_channel', state: { key: 'value' }) do |envelope|
    puts envelope.status
end

Get State

pubnub.state(channel: :my_channel, uuid: 'some-uuid') do |envelope|
    puts envelope.result[:data][:state]
end

Response

#<Pubnub::Envelope:0x007fd3851b5cc8
    @result = {
        :data => {
            :state => {
                "age"=>59,
                "first" => "Robert",
                "last" => "Plant"
            },
            :channel=>"whatever"
        }
    },
    @status = {
        :code => 200
    }
>

Here Now​

Requires Presence

Cache

Method(s)​

Basic Usage​

Get a list of uuids subscribed to channel​

Reference code

Response​

Where Now​

Requires Presence

Timeout events

Method(s)​

Basic Usage​

Get a list of channels a UUID is subscribed to​

Response​

User State​

Requires Presence

Method(s)​

Basic Usage​

Set State​

Get State​

Response​

Here Now

Method(s)

Basic Usage

Get a list of uuids subscribed to channel

Response

Where Now

Method(s)

Basic Usage

Get a list of channels a UUID is subscribed to

Response

User State

Method(s)

Basic Usage

Set State

Get State

Response