About the Envelope Field
All publishable document types contain an envelope (_env) field. This field is a document reference to the pub:publish:envelope document type. The envelope is much like a header in an e-mail message. The pub:publish:envelope document type defines the content and structure of the envelope that accompanies the published document. The envelope records information such as the sender’s address, the time the document was sent, sequence numbers, and other useful information for routing and control.
Because the _env field is needed for publication, Designer controls the usage of the _env field in the following ways:
You cannot insert an
_env field in a document type.
Designer automatically inserts the
_env field as the last field in the document type when you make the document type publishable.
You cannot copy and paste the
_env field from one document type to another. You can copy and paste this field to the Input/Output tab or into a specification.
You cannot move, rename, cut, or delete the
_env field from a document type.
Designer automatically removes the
_env field when you make a document type unpublishable.
The
_env field is always the last field in a publishable document type.
For more information about the _env field and the contents of the pub:publish:envelope document type, see the webMethods Integration Server Built-In Services Reference.
Note: If an IS document type contains a field named _env, you need to delete that field before you can make the IS document type publishable.