[DAFFODIL-1781] layer transformer for ASN.1 Object Identifier

• Type: New Feature
• Status: Closed
• Priority: Trivial
• Resolution: Abandoned
• Component/s: Back End, DFDL Language, Front End
• Assignee: Unassigned
• Reporter: Mike Beckerle
• Created: 01/Jun/17 22:49
• Updated: 11/Jun/21 20:07
• Resolved: 30/Jul/20 13:40

Description

Some data types are encoded in ways we can't decode.

Good example of this is an ASN.1 DER "Object Identifier".

Another good example of this is a Google Protocol Buffers zig-zag integer.

Another example of this is the payload of a mil-std-2045 header - the payload can be specified as "compressed", and must be decompressed when parsing, recompressed when unparsing.

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This ticket may be mixing some issues.

• Primitive representations of string, int, etc.
• decoding of a representation before subsequently parsing it, or the inverse for unparsing

In general DFDL/Daffodil needs extensibility of this kind, so that every time someone runs into a format with some encoding not anticipated by the DFDL standard we don't have to add it into the Daffodil implementation as a special case.

We need the ability to extend by adding a jar of specifically-setup libraries, and augmenting a schema with declarations that the extension be added.