Message Attachments

An attachment is a piece of data extracted from the raw incoming message and stored separately. Attachments are not associated with connector messages, but instead with the overall message. The extraction happens at the very beginning of the message lifecycle, even before the preprocessor script runs. When a destination connector dispatches data outbound, any attachments associated with the message will be automatically re-inserted into the outgoing data. In this way, attachment data is only stored once, and multiple copies of it for each connector and for each content type (e.g. Raw / Transformed / Encoded) will not be stored. Using attachments can greatly improve the memory footprint of your channels.

More additional information on attachments and how they are extracted, see Attachment Handlers.