automated tagging based on tagging

[schaarsc]

Is your feature request related to a problem? Please describe. I'd like to suggest to add the ability to trigger actions after a tag is assigned or removed

Describe the solution you'd like similar to the automated tagging for files during upload, for example:

• if tag "Paris" is added, also add tag "France"
• if tag "Archive" is added, then compress file and add tag "keep_for_ten_years"
• if tag "Work in progess" is removed, add tag "keep_for_one_year"

as in #10425 it would be nice if a rule could be applied to files that were on the sever before the rule was created.

[schaarsc]

I've created a proof of concept based on v16. It requires changes to the app and to the server

• https://github.com/schaarsc/files_automatedtagging/tree/14229-automated-tagging-based-on-tags
  • CacheListener: add listener for MapperEvent
• https://github.com/schaarsc/server/tree/14229-automated-tagging-based-on-tags
  • SystemTagObjectMapper: only fire event for new tag, not for all tags. This is required to avoid a loop.
  • FileSystemTags: disable tag cache in Check otherwise tag added by previous Check is not visible in next Check

Problems with this proof of concept:

• disabling the cache might have impact on big installations, some kind of cache invalidation is required
• tags are added on server side, user will not see them until page refresh
• the checkOperations has no access to the event, which makes EVENT_UNASSIGN difficult to implement
• by adding listener for MapperEvent checks are executed more often. I don't know the impact this will have on large installations ... different checks for onMapperEvent / onCacheEvent could be an option.

[Spartachetto]

Take into account that this should be strongly related to the on going work to solve issue #12790 (Workflow Improvements)

[schaarsc]

proof of concept on top of stable18: https://github.com/schaarsc/server/tree/stable18-14229-automated-tagging-based-on-tags https://github.com/schaarsc/files_automatedtagging/tree/stable18-14229-automated-tagging-based-on-tags

Changes:

• changes to lib/private/SystemTag/SystemTagObjectMapper.php are no longer required, this has been fixed in NC18
• in apps/workflowengine/lib/Check/FileSystemTags.php instead of disabling the cache, only invalidate in case of a match

[schaarsc]

turns out that apps/workflowengine/lib/Check/FileSystemTags.php may be a little bit tricky ...

• the class is only instanciated once, so the internal systemTag cache has to be disabled, since listening to events did not solve the problem of a stale systemTags cache and the same instance is reused for all checks
• getFileIds() returns a list of ids including the parents, getSystemTags() is using all those ids to find tags, so in the end tags on parent folders may unintentionally propagate to files. Is this a bug or a feature?
• getFileIds() does not return any ids for files shared by other users, so getSystemTags() cannot find any tags and all checks for systemTags will fail. Or in other words if UserA tags a file F getSystemTags() returns a list of tags, if the same file is tagged by UserB getSystemTags() returns an empty list and checks fail

does anyone have an idea how to workaround these issues? and whether including system tags from parents and ignoring shared files is a design decision or a bug?

[szaimen]

Hi there, do you mind creating a PR with your patches for discussion? Thank you!

[ghost]

This issue has been automatically marked as stale because it has not had recent activity and seems to be missing some essential information. It will be closed if no further activity occurs. Thank you for your contributions.