...

PUT /apps/{app-name} -H 'Content-Type: application/json' -d '{
  "artifact": { ... },
  "config": { ... },
  "dryrun": true
}'

Specific to Hydrator, the etl apps could put the 'pipeline spec', which contains each stage, the artifact used for each plugin, and the input/output schema for each stage, in a program property. The UI could then read this information as well, instead of trying to manage schema themselves.

New Plugins

Kinesis source:

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