• Added support for sending periodic 'ping' requests to the server. These are mainly useful to keep connections alive and active if they traverse network firewalls that may terminate tcp connections periodically if traffic has not been exchanged between the endpoints. This feature is disabled by default, but can be turned on by setting opts.enablePing when calling Srf#connect or Srf#listen, e.g.

srf.connect({
  host: '127.0.0.1',
  port: 9022,
  secret: 'cymru',
  enablePing: true
});

The default ping interval is 15 seconds. You can change this by setting opts.pingInterval to a value of milliseconds (must be >= 5000 and <= 300000); for instance, to set the ping interval to 45 seconds:

srf.connect({
  host: '127.0.0.1',
  port: 9022,
  secret: 'cymru',
  enablePing: true,
  pingInterval: 45000
});

The server responds with a 'pong' message (note that you do not need to do anything to handle this; it is not exposed to the application level).

This feature requires a drachtio server version of v0.8.2 or above; however, it is safe to call it against earlier versions (there just won't be any ping messages sent).

• add Srf#findDialogById and Srf#findDialogByCallIDAndFromTag, the latter is particularly useful in handling attended transfer scenarios per issue #34
• migrated by istanbul to nyc for code coverage