Set removal time batch operation useless when configuring history level to none

[ThorbenLindhauer]

This issue was imported from JIRA:

Field	Value
JIRA Link	CAM-14931
Reporter	@tasso94
Has restricted visibility comments	true

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Environment (Required on creation):

Any still supported Camunda 7 version.

Description (Required on creation; please attach any relevant screenshots, stacktraces, log files, etc. to the ticket):

• High amounts of history were produced in the past
• Producing history is temporarily disabled by changing the history level to NONE
  • Reason: performance of process execution is degraded due to high amounts of history data
• A removal time should be assigned to the history data to clean it up
• The batch operation to set a removal time to historic process instances doesn't work since the history level is configured to NONE

Steps to reproduce (Required on creation):

• Configure the history level to FULL
• Start a process instance
• Configure the history level to NONE
• Perform the batch operation "Set removal time to process instances" on the historic process instance

Observed Behavior (Required on creation):

The removal time is not set.

Expected behavior (Required on creation):

Removal time is set.

Root Cause (Required on prioritization):

The historic process instance query returns an empty list when the history level is configured to NONE <1>.

Solution Ideas (Optional):

1. Introduce a new built-in history level that doesn't produce history but allows to perform queries.

• Cons
  • Cockpit might not be usable since history queries take a very long to return

1. Register a custom history level that doesn't produce history but allows to perform queries.

• Cons
  • User needs to write custom code

1. Prevent disabling history queries for batch operations needed for history cleanup.

• Cons
  • There might be other scenarios in which querying for history data is beneficial that cannot be achieved with this solution

Hints (optional):

<1> https://github.com/camunda/camunda-bpm-platform/blob/master/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/HistoricProcessInstanceManager.java#L106

Links:

[garima-camunda]

Related support tickets

• https://jira.camunda.com/browse/SUPPORT-14712
• https://jira.camunda.com/browse/SUPPORT-16802

[garima-camunda]

Here is another support ticket https://jira.camunda.com/browse/SUPPORT-19568 where customer could not use Batch Operation in Cockpit to delete "running process instances" because history level was set as "none". ( please see this screenshot)

@toco-cam , @tasso94 - fyi

[toco-cam]

@tasso94 will take care of this and schedule it for a later patch (> 7.20.5)