getPackingSlip

the postal.fedx.getPackingSlip( type [, arg1, arg2, etc. ]) method returns a federation "packingSlip" - a wrapper for your message that is specific to postal.federation. There are four types of packing slips:

• ping - this is used when one postal instance is attempting to ping a remote instance, to set up federation.
• pong - this is used when replying to another instance's ping message
• bundle - this is a generic wrapper that allows multiple packing slips to be transmitted as one message (primarily as an option to keep transport chatter to a minimum)
• message - the most commonly used packingSlip. It's meant to wrap a postal message envelope before it is sent to the remote instance(s).

In addition to the type argument, additional arguments can be passed that may be used in the packing-slip-specific handler. Currently, these are the possible method signatures:

• getPackingSlip("ping")
• getPackingSlip("pong", originalPingPackingSlip)
• getPackingSlip("bundle", packlingSlipsArray)
• getPackingSlip("message", envelope)

Note that you don't ever have to call getPackingSlip directly (unless you are writing a federation transport plugin).