I have done a bunch of improvements to the code for this layer loading based on the prior PR.
It is now stabilized and worth it to examine/reexamine the PR at this point. https://github.com/apache/daffodil/pull/651 I have also changed the goals here somewhat. I split out the defining/creation of a Java API for layers, and true dynamic loading via service loaders into a separate JIRA ticket DAFFODIL-2567. I think that experience with what we have so far makes sense before defining any Java API for doing this. I also think the need for true dynamic detect and load behavior is far less critical than the basic ability to define these in external jars that aren't part of daffodil. This PR now includes just the modularization of layers, so they can be written in scala and defined in a jar outside of Daffodil, An application must register them for use by calling LayerCompilerRegistry.register(...). All the built-in layers are in daffodil-runtime1-layers which is a new module. Other layers are defined in daffodil-test for testing that checksums/check digits work. The example AIS payload encoding layer is also now defined and tested in daffodil-test. On Sat, Sep 25, 2021 at 8:31 PM Mike Beckerle <mbecke...@apache.org> wrote: > Please see: > https://cwiki.apache.org/confluence/display/DAFFODIL/Proposal%3A+Dynamically+loading+Layer+Transformations > > Also: https://issues.apache.org/jira/browse/DAFFODIL-1927 > > See related PR: https://github.com/apache/daffodil/pull/643 which is for > https://issues.apache.org/jira/browse/DAFFODIL-2221 > > Please add comments or directly edit that wiki page, or discuss in this > email thread if you prefer. > >
