Connector customization under ESMX

[theurich]

Currently Connectors cannot be specialized (anything but default implementation) or even customized (setting specific attributes) when using ESMX. This limits the flexibility of the ESMX approach, e.g. a user cannot even set the standard NUOPC Connector attributes on a specific Connector!

One way this situation could be resolved is to make in esmxRun.yaml the runSequence item under Driver required, and instead make componentList optional. Then we could have the ESMX_Driver process the explicitly specified components in esmxRun.yaml and automatically generate the componentList. This would need to be compared to the components determined from the runSequence. Connectors not explicitly defined will continue to be added automatically following NUOPC autoAddConnectors=.true. rules, as before. However, this approach also supports explicit specification of Connector components.

As a first implementation the explicit Connector specification should support the attributes map. Long run I think a connector specialization item should also be supported to link against specialized Connector implementation code.

[theurich]

A specific use-case for this feature has come up under the Navy-ESPC work where I wanted to quickly set EpochEnable=false on some of the Connectors to test the impact. Setting an attribute like this on a Connector cannot be easily done under ESMX without the requested feature.

This is not currently critical for Navy-ESPC development, but it is an annoying limitation of the current ESMX implementation.

[anntsay]

Ufuk: had asked for similar feature but already has a workaround/other implementation. therefore not as urgent.

Gerhard: however, there is limits on setting attributes in connector. this feature request is a cleaner path.