Major Description
Current functionality
A user can select the remove duplicate option in the start adapter tab and select the time interval how long events are stored in cache (class: org.apache.streampipes.connect.adapter.preprocessing.transform.stream.DuplicateFilterPipelineElement)
Problems
- The state is not persisted when an adapter is restarted
- No option to ignore the timestamp field
New functionality
- A user should be able to add the remove duplicate rule with the option to ignore the timestamp field.
- A user should be able to restart an adapter without loosing the state of the remove duplicate rule
Info
- To do that we need to extend the API of adapters and add the functionality to execute code when an adapter is stopped
- An API to load data (on startup) and persist (on shutdown) for elements is required