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API Reference

Connection

Connection PropertiesARTConnection PropertiesAbly::Realtime::Connection Attributesio.ably.lib.realtime.Connection MembersIO.Ably.Realtime.Connection Properties

The Connection object exposes the following public propertiesattributesmembers:

idId

A unique public identifier String for this connection, used to identify this member in presence events and messages.

stateState

The current io.ably.lib.realtime.ConnectionState stateIO.Ably.Realtime.ConnectionState stateAbly::Realtime::Connection::STATE stateARTRealtimeConnectionState statestate String of this Connection. See the Connection states for more information.

errorReasonreasonErrorReasonerror_reason

When a connection failure occurs this attributememberproperty contains the ErrorInfoAblyException.

keyKey

A unique private connection key String used to recover or resume a connection, assigned by Ably. When recovering a connection explicitly, the recoveryKeyrecovery_key is used in the recover client options as it contains both the key and the last message serial.

This private connection key can also be used by other REST clients to publish on behalf of this client. See the publishing over REST on behalf of a realtime client documentation for more info.

recoveryKeyrecovery_keyRecoveryKey

The recovery key String can be used by another client to recover this connection’s state in the recoverRecover client options propertymemberattribute. See connection state recover options for more information.

serialSerial

The serial number Integer of the last message to be received on this connection, used automatically by the library when recovering or resuming a connection. When recovering a connection explicitly, the recoveryKeyrecovery_keyRecoveryKey is used in the recoverRecover client options as it contains both the key and the last message serial.

Connection MethodsARTConnection MethodsAbly::Realtime::Connection Methodsio.ably.lib.realtime.Connection MethodsIO.Ably.Realtime.Connection Methods

connectConnect

connect()Deferrable connect → yields Connectionvoid connect()void Connect()

Explicitly calling connectConnect is unnecessary unless the ClientOptions attribute autoConnectauto_connectAutoConnect is false. Unless already connected or connecting, this method causes the connection to open, entering the connecting state.

Returns

A Deferrable object is returned from this method.

On successfully connecting to Ably, the registered success blocks for the Deferrable and any block provided to this method yields a Connection object.

Failure to connect will trigger the errback callbacks of the Deferrable with an ErrorInfo object containing an error response as defined in the Ably REST API documentation.

closeClose

close()Deferrable close → yields Connectionvoid close()void Close()

Causes the connection to close, entering the closing state. Once closed, the library will not attempt to re-establish the connection without an explicit call to connect()Connect()connect":#connect.

Returns

A Deferrable object is returned from this method.

On successfully closing the connection, the registered success blocks for the Deferrable and any block provided to this method yields a Connection object.

Failure to close the connection will trigger the errback callbacks of the Deferrable with an ErrorInfo object containing an error response as defined in the Ably REST API documentation.

onOn

There are threetwo overloaded versions of this method:

on(String event, listener(ConnectionStateChange stateChange))on(ConnectionEvent *event) → yields ConnectionStateChangevoid on(ConnectionEvent event, ConnectionStateListener listener)on(event: ARTRealtimeConnectionEvent, call: (ARTConnectionStateChange?) → Void) → ARTEventListenervoid On(ConnectionEvent event, Action<ConnectionStateChange> action)

Register the given listener blockfunctionaction for the specified ConnectionEvent on the Connection. The listener is passed a ConnectionStateChange object that contains the current state, previous state, and an optional reason for the event or state change.

on(String[] events, listener(ConnectionStateChange stateChange))

Same as above, but registers multiple listeners, one for each event in the array.

on(listener(ConnectionStateChange stateChange))on → yields ConnectionStateChangevoid on(ConnectionStateListener listener)on(call: (ARTConnectionStateChange?) → Void) → ARTEventListenervoid On(Action<ConnectionStateChange> action)

Register the given listener blockfunctionaction for all ConnectionEvents on the Connection. The listener is passed a ConnectionStateChange object that contains the current state, previous state, the event, and an optional reason for the event or state change. (For the update event, the current and previous states will be the same).

If an exception is thrown in the listener and bubbles up to the event emitter, it will be caught and logged at error level, so as not to affect other listeners for the same event

Parameters

event(s)
the connection event(s) to subscribe to
Type: String or String[]
event
the connection event to subscribe to
Type: ConnectionEvent
event
the connection event to subscribe to
Type: ConnectionEvent
event
the connection event as a Symbol such as :connected or ConnectionEvent object to subscribe to
Type: ConnectionEvent
event
the connection event to subscribe to
Type: ARTRealtimeConnectionEvent
listener
is a function of the form function(stateChange) to be notified for matching events
listener
listener to be notified for matching events
Type: ConnectionStateListener
action
action to be executed for matching events
Type: ConnectionStateChange
&block
listener block that is yielded to for matching events
call
called with matching events

Example

Browser ConnectionState change example

onceOnce

There are two overloaded versions of this method:

once(String event, listener(ConnectionStateChange stateChange))once(ConnectionEvent *event) → yields ConnectionStateChangevoid once(ConnectionEvent event, ConnectionStateListener listener)once(event: ARTRealtimeConnectionEvent, call: (ARTConnectionStateChange?) → Void) → ARTEventListenervoid Once(ConnectionEvent event, Action<ConnectionStateChange> action)

Register the given listener blockfunctionaction for a single occurrence of the specified ConnectionEvent on the Connection. Once the listener has been called, it is removed as a registered listener and will not be called again. The listener is passed a ConnectionStateChange object that contains the current state, previous state, the event, and an optional reason for the state change. (For the update event, the current and previous states will be the same).

once(listener(ConnectionStateChange stateChange))once → yields ConnectionStateChangevoid once(ConnectionStateListener listener)once(call: (ARTConnectionStateChange?) → Void) → ARTEventListenervoid Once(Action<ConnectionStateChange> action)

Register the given listener blockaction for a single occurrence of any ConnectionEvent on the Connection. Once the listener has been called, it is removed as a registered listener and will not be called again. The listener is passed a ConnectionStateChange object that contains the current state, previous state, and an optional reason for the state change. (For the update event, the current and previous states will be the same).

If an exception is thrown in the listener and bubbles up to the event emitter, it will be caught and logged at error level, so as not to affect other listeners for the same event

Parameters

event(s)
the connection event(s) to subscribe to
Type: String or String[]
event
the connection event to subscribe to
Type: ConnectionEvent
event
the connection event to subscribe to
Type: ConnectionEvent
event
the connection event as a Symbol such as :connected or ConnectionEvent object to subscribe to
Type: ConnectionEvent
event
the connection event to subscribe to
Type: ARTRealtimeConnectionEvent
listener
is a function of the form function(stateChange) to be notified for a single occurrence of a matching event
listener
listener to be notified for a single occurrence of a matching state change
Type: ConnectionStateListener
action
action to be executed for matching state changes
Type: ConnectionStateChange
&block
listener block that is yielded to for a single occurrence of a matching event
call
called with matching events
offOff

There are sixtwo overloaded versions of this method:

off(String event, listener)off(ConnectionEvent *event, &block)void off(ConnectionEvent event, ConnectionStateListener listener)off(event: ARTRealtimeConnectionEvent, listener: ARTEventListener)void Off(ConnectionEvent event, Action<ConnectionStateChange> action)

Remove the given listener blockaction for the ConnectionEvent.

off(listener)off(&block)void off(ConnectionStateListener listener)off(listener: ARTEventListener)void Off(Action<ConnectionStateChange> action)

Remove the given listener blockaction for all ConnectionEvents

off(String[] states, listener)

Removes the given listener from all ConnectionEvents in the array.

off(String state)

Removes all listeners for a given @[email protected]

off(String[] states)

Removes all listeners for all ConnectionEvents in the array.

off()

Removes all listeners (including both those registered against specific events and those registered without an event).

Parameters

event(s)
the connection event(s) to unsubscribe from
Type: String or String[]
event
the connection event to unsubscribe from
Type: ConnectionEvent
event
the connection event to subscribe to
Type: ConnectionEvent
event
the connection event as a Symbol such as :connected or ConnectionEvent object to unsubscribe from
Type: ConnectionEvent
event
the connection event to unsubscribe from
Type: ARTRealtimeConnectionEvent
listener
is the listener function to be removed
listener
is the listener to be removed
Type: ConnectionStateListener
action
action to be executed for matching event changes
Type: ConnectioneventChangeEventArgs
&block
is the listener block to be removed
listener
previous return value from a on or once call
pingPing

ping(callback(ErrorInfo err, Number responseInMilliseconds))Deferrable ping → yields Float secondsvoid ping(CompletionListener listener)ping(callback: (ARTErrorInfo?) → Void)void Ping(Action<TimeSpan?, ErrorInfo> callback)

When connected, sends a heartbeat ping to the Ably server and executes the callback with any error and the response time in millisecondsexecutes the callbackcalls the listeneryields the elapsed time in seconds when a heartbeat ping request is echoed from the server. This can be useful for measuring true round-trip latency to the connected Ably server.

Returns

A Deferrable object is returned from this method.

On successfully echoing a heartbeat from Ably, the registered success blocks for the Deferrable and any block provided to this method yields a Float representing the time in seconds for the heartbeat ping request to be echoed.

Failure to receive a heartbeat ping will trigger the errback callbacks of the Deferrable with an ErrorInfo object containing an error response as defined in the Ably REST API documentation.

io.ably.lib.realtime.CompletionListener

A io.ably.lib.realtime.CompletionListener is an interface allowing a client to be notified of the outcome of an asynchronous operation.

public interface CompletionListener {
  // Called when the associated operation completes successfully,
  public void onSuccess();

  // Called when the associated operation completes with an error.
  public void onError(ErrorInfo reason);
}

ConnectionStateARTRealtimeConnectionStateConnection::STATE Enumio.ably.lib.realtime.ConnectionState EnumIO.Ably.Realtime.ConnectionState Enum

ConnectionState is a String with a value matching any of the Realtime Connection states.

var ConnectionStates = [
  'initialized',
  'connecting',
  'connected',
  'disconnected',
  'suspended',
  'closing',
  'closed',
  'failed'
]

io.ably.lib.realtime.ConnectionState is an enum representing all the Realtime Connection states.

public enum ConnectionState {
  initialized,   // 0
  connecting,    // 1
  connected,     // 2
  disconnected,  // 3
  suspended,     // 4
  closing,       // 5
  closed,        // 6
  failed         // 7
}

IO.Ably.Realtime.ConnectionState is an enum representing all the Realtime Connection states.

public enum ConnectionState
{
    Initialized,    //0
    Connecting,     //1
    Connected,      //2
    Disconnected,   //3
    Suspended,      //4
    Closing,        //5
    Closed,         //6
    Failed          //7
};

Ably::Realtime::Connection::STATE is an enum-like value representing all the Realtime Connection states. STATE can be represented interchangeably as either symbols or constants.

Symbol states

:initialized # =>  0
:connecting # =>   1
:connected # =>    2
:disconnected # => 3
:suspended # =>    4
:closing # =>      5
:closed # =>       6
:failed # =>       7

Constant states

Connection::STATE.Initialized # =>  0
Connection::STATE.Connecting # =>   1
Connection::STATE.Connected # =>    2
Connection::STATE.Disconnected # => 3
Connection::STATE.Suspended # =>    4
Connection::STATE.Closing # =>      5
Connection::STATE.Closed # =>       6
Connection::STATE.Failed # =>       7

Example usage

# Example with symbols
client.connection.on(:connected) { ... }

# Example with constants
client.connection.on(Ably::Realtime::Connection::STATE.Connected) { ... }

# Interchangeable
Ably::Realtime::Connection::STATE.Connected == :connected # => true

ARTRealtimeConnectionState is an enum representing all the Realtime Connection states.

typedef NS_ENUM(NSUInteger, ARTRealtimeConnectionState) {
    ARTRealtimeInitialized,
    ARTRealtimeConnecting,
    ARTRealtimeConnected,
    ARTRealtimeDisconnected,
    ARTRealtimeSuspended,
    ARTRealtimeClosing,
    ARTRealtimeClosed,
    ARTRealtimeFailed
};
public enum ARTRealtimeConnectionState : UInt {
    case Initialized
    case Connecting
    case Connected
    case Disconnected
    case Suspended
    case Closing
    case Closed
    case Failed
}

ConnectionState is an enum representing all the Realtime Connection states.

const (
  StateConnInitialized = 1
  StateConnConnecting = 2
  StateConnConnected = 4
  StateConnDisconnected = 8
  StateConnSuspended = 16
  StateConnClosing = 32
  StateConnClosed = 64
  StateConnFailed = 128
)

ConnectionEventARTRealtimeConnectionEventConnection::EVENT Enumio.ably.lib.realtime.ConnectionEvent EnumIO.Ably.Realtime.ConnectionEvent Enum

ConnectionEvent is a String that can be emitted as an event on the Connection object; either a Realtime Connection state or an update event.

var ConnectionEvents = [
  'initialized',
  'connecting',
  'connected',
  'disconnected',
  'suspended',
  'closing',
  'closed',
  'failed',
  'update'
]

io.ably.lib.realtime.ConnectionEvent is an enum representing all the events that can be emitted be the Connection; either a Realtime Connection state or an update event.

public enum ConnectionEvent {
  initialized,   // 0
  connecting,    // 1
  connected,     // 2
  disconnected,  // 3
  suspended,     // 4
  closing,       // 5
  closed,        // 6
  failed,        // 7
  update         // 8
}

IO.Ably.Realtime.ConnectionEvent is an enum representing all the events that can be emitted be the Connection; either a Realtime Connection state or an Update event.

public enum ConnectionState
{
    Initialized,    //0
    Connecting,     //1
    Connected,      //2
    Disconnected,   //3
    Suspended,      //4
    Closing,        //5
    Closed,         //6
    Failed,         //7
    update          //8
};

Ably::Realtime::Connection::EVENT is an enum-like value representing all the events that can be emitted be the Connection; either a Realtime Connection state or an :update event. EVENT can be represented interchangeably as either symbols or constants.

Symbol states

:initialized # =>  0
:connecting # =>   1
:connected # =>    2
:disconnected # => 3
:suspended # =>    4
:closing # =>      5
:closed # =>       6
:failed # =>       7
:update # =>       8

Constant states

Connection::EVENT.Initialized # =>  0
Connection::EVENT.Connecting # =>   1
Connection::EVENT.Connected # =>    2
Connection::EVENT.Disconnected # => 3
Connection::EVENT.Suspended # =>    4
Connection::EVENT.Closing # =>      5
Connection::EVENT.Closed # =>       6
Connection::EVENT.Failed # =>       7
Connection::EVENT.Update # =>       8

Example usage

# Example with symbols
client.connection.on(:connected) { ... }

# Example with constants
client.connection.on(Ably::Realtime::Connection::STATE.Connected) { ... }

# Interchangeable
Ably::Realtime::Connection::STATE.Connected == :connected # => true

ARTRealtimeConnectionEvent is an enum representing all the events that can be emitted be the Connection; either a Realtime Connection state or an Update event.

typedef NS_ENUM(NSUInteger, ARTRealtimeConnectionEvent) {
    ARTRealtimeConnectionEventInitialized,
    ARTRealtimeConnectionEventConnecting,
    ARTRealtimeConnectionEventConnected,
    ARTRealtimeConnectionEventDisconnected,
    ARTRealtimeConnectionEventSuspended,
    ARTRealtimeConnectionEventClosing,
    ARTRealtimeConnectionEventClosed,
    ARTRealtimeConnectionEventFailed,
    ARTRealtimeConnectionEventUpdate
};
public enum ARTRealtimeConnectionEvent : UInt {
    case Initialized
    case Connecting
    case Connected
    case Disconnected
    case Suspended
    case Closing
    case Closed
    case Failed
    case Update
}

ConnectionEvent is a String that can be emitted as an event on the Connection object; either a Realtime Connection state or an update event.

const (
  StateConnInitialized = 1
  StateConnConnecting = 2
  StateConnConnected = 4
  StateConnDisconnected = 8
  StateConnSuspended = 16
  StateConnClosing = 32
  StateConnClosed = 64
  StateConnFailed = 128
)

io.ably.lib.realtime.ConnectionStateListener

A io.ably.lib.realtime.ConnectionStateListener is an interface allowing a client to be notified of connection state change. See Connection#on to register a listener for one or more events.

public interface ConnectionStateListener {
  // Called when the connection state changes
  public void onConnectionStateChanged(ConnectionStateListener.ConnectionStateChange state);
}

ConnectionStateChange ObjectARTConnectionStateChangeio.ably.lib.realtime.ConnectionStateListener.ConnectionStateChangeConnectionStateChangeIO.Ably.Realtime.ConnectionStateChange

A io.ably.lib.realtime.ConnectionStateListener.ConnectionStateChangeAbly::Models::ConnectionStateChangeARTConnectionStateChangeIO.Ably.Realtime.ConnectionStateChangeConnectionStateChange is a type encapsulating state change information emitted by the Connection object. See Connection#on to register a listener for one or more events.

PropertiesMembersAttributes

currentCurrent
the new state
Type: State StringConnection::STATEConnectionState
previousPrevious
the previous state. (for the update event, this will be equal to the current state)
Type: State StringConnection::STATEConnectionState
eventEvent
the event that triggered this state change
Type: ConnectionEventConnection::[email protected]
reasonReason
an ErrorInfo containing any information relating to the transition
Type: ErrorInfo
retryInretry_inRetryIn
Duration upon which the library will retry a connection where applicable, as millisecondssecondsa Timespan
Type: IntegerTimespanLong Integer

LastConnectionDetails

A LastConnectionDetails object provides details on the last connection in a browser environment persisted when the window beforeunload fired. This object is provided to the callback specified in the recover attribute of ClientOptions. The callback in turn instructs the client library whether the connection should be recovered or not. See connection state recovery for more information.

Please note that as sessionStorage is used to persist the LastConnectionDetails between page reloads, it is only available for pages in the same origin and top-level browsing context.

Properties

recoveryKey
An opaque string obtained from the recoveryKey attribute of the Connection object before the page was unloaded. This property is used by the library to recover the connection
Type: String
disconnectedAt
the time at which the previous library was abruptly disconnected before the page was unloaded. This is represented as milliseconds since epoch
Type: Integer
location
a clone of location object of the previous page’s document object before the page was unloaded. A common use case for this attribute is to ensure that the previous page URL is the same as the current URL before allowing the connection to be recovered. For example, you may want the connection to be recovered only for page reloads, but not when a user navigates to a different page
Type: String
clientId
the clientId of the client’s Auth object before the page was unloaded. A common use case for this attribute is to ensure that the current logged in user’s clientId matches the previous connection’s clientId before allowing the connection to be recovered. Ably prohibits changing a clientId for an existing connection, so any mismatch in clientId during a recover will result in the connection moving to the failed state
Type: String

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