Track fragment changes

[tomaszmichalak]

Is your feature request related to a problem? Please describe.
Currently, only the final fragment state (payload and body) is available for execution log consumers.

Describe the solution you'd like
We want to track all fragment changes per node. So in Knot.x Chrome Extension we can click on the node and see fragment details.

Additional context
This should be an option, it can influence the performance.

[marcinus]

Proposed solution:

1. Enhance EventLogEntry, NodeExecutionData.Response and GraphNodeResponseLog with optional Fragment fragment field
2. Change EventLogEntry.success(...) to store Fragment resulting from just succeded operation
3. Modify EventLogConverter::getExecutionData(String id) to populate response in NodeExecutionData when transition == null (which does not happen now) and enhance it with Fragment object from EventLogEntry if present.
4. Modify MetadataConverter::setGraphLogPropertiesFrom(GraphNodeExecutionLog graphLog, NodeExecutionData executionData) to populate logged Fragment to the consumer (trivial)

The problem with this solution is turning logging on/off. Currently, TaskExecutionContext which performs the logging is not configurable, neither is TaskEngine nor FragmentsEngine. Populating configuration from FragmentsHandler will require changing and cascading these changes down to execution logic - which in my opinion already became pretty complicated.
Perhaps it would be a good moment to refactor/modularize it further?

@tomaszmichalak could you share your point of view on these issues?

[tomaszmichalak]

Please extend GraphNodeResponseLog with fragment.

[tomaszmichalak]

In scope:

• update EventLogEntry for all cases: success, error, other
• propagate data from FragmentEvents to GraphNodeResponseLog