feat: add alert rule options to not send alert on state recovery and to send regardless of state change

[mmdoogie]

This was previous requested in #3723 that went stale. I recently had a use case for it and decided to add it.

Added a checkbox to the alert rule builder that's used to determine whether or not to include noRecoveries in the TICKscript.
I also saw that stateChangesOnly was already in the structure so I exposed that in a similar manner.

Additionally, the swagger.json didn't look like it matches the current response to the API even before the changes, it was fixed with a new flag added.

• CHANGELOG.md updated with a link to the PR (not the Issue)
• Well-formatted commit messages
• Rebased/mergeable
• Tests pass
• swagger.json updated (if modified Go structs or API)
• Sign CLA (if not already signed)

[sranka]

Thank you @mmdoogie for your contribution. Can you please change your commit messages to semantic format ? For example:

• chore: update CHANGELOG
• feat(kapacitor): add option to set noRecoveries on alerts

[mmdoogie]

Updated messages as requested. Also synced up the swagger.json with the existing state of alerts/alertNode from the codebase and added the new object parameter.

[sranka]

Thank you for updating the swagger file to be closer to reality. It still needs some polishing to be approved.

• every new alert must be created with a generated ID
• kapacitor/ast_test.go needs to test the new noRecoveries property
• UI must be improved

[sranka]

@mmdoogie please let me know if you need help with the changes.

[mmdoogie]

Sorry it has taken me a moment to get back to this. UI rearranged and better spaced now, definitely better:

also not present unless a handler has been added:

Will add a test for the new parameters and fix the ID part soon.

[mmdoogie]

There's an interaction with the pipeline/tick/AST code in kapacitor -- when a new rule is created and POSTed to chronograf, the kapacitor/alerts.go addAlertNodes uses that functionality to build the alert nodes tickscript. It appears to be parsing the flags correctly up to that point but the build/format process only returns the actual alert nodes and not any of the flag parameters.

[sranka]

There's an interaction with the pipeline/tick/AST code in kapacitor -- when a new rule is created and POSTed to chronograf, the kapacitor/alerts.go addAlertNodes uses that functionality to build the alert nodes tickscript. It appears to be parsing the flags correctly up to that point but the build/format process only returns the actual alert nodes and not any of the flag parameters.

This was a UI issue that you already fixed in d806ba8, and I also modified a test to cover it in 592d2d5

[sranka]

Thank you @mmdoogie for addressing my feedback. I rebased your changes on top of the latest master and also tested the new functionality manually to see it in action. It works fine. I also added an extra test to verify that the flags are kept when updating alert nodes.