= Trac Batch Modification Proposal =

''Proposal to add batch ticket modification functionality to Trac. See #525 for the original ticket.''

== The Context ==
Currently Trac does not support modifying a batch of tickets at once. This is only supported through the use of the !BatchModifyPlugin found at http://trac-hacks.org/wiki/BatchModifyPlugin. Moving this into Trac has been a commonly requested feature for years.

== Code ==
You can check out progress at http://github.com/CuriousCurmudgeon/trac-batch-modify

== Requirements ==
=== UI ===
The current plugin UI does not fit at all with Trac. What about something similar to the custom query filter UI? Users would select the items they want to modify on each ticket, similar to how filters are added now.

 This has been implemented in the 0.7.0 release of the plugin.
  (cboos) This looks good to me. Time for an integration branch, don't you think? See below.


=== Notifications ===
The current plugin does not integrate with email notifications. This could be done the "normal" way via the ITicketChangeListener once #7758 is done (or the planned new IResourceChangeListener  (#8834) and the Announcer support). That would be a first step.

A specific interface (or extra method to the IResourceChangeListener interface) may be more appropriate though, like it would be for other cases of batch modifications, such as #4582 and #5658, or the batch WikiRename feature, see ticket:4412#comment:8.

 We definitely should try to **not** send 100s mails to the same user. A mail summarizing the changes should be enough. (cboos)

=== Timeline ===
Should each batch modification add one entry to the timeline, or a separate entry for each ticket that was modified?

 Here as well we could have one summarizing event. See also #9205. (cboos)

=== Permissions ===
The plugin adds a separate permission for batch modification. This seems to be preferred by users of the plugin who do not want every ticket editor to necessarily be able to batch modify them.

  (osimons) I do not like the separate permission, and to me it makes no sense. If you are allowed to change each ticket, then surely you should be allowed to modify them through a batch update? If the feature is to become an integrated part of Trac, then the `TRAC_BATCH_MODIFY` permission just adds complexity and administrative overhead.

=== Workflows ===
The plugin as currently written allows for tickets to be put into an inconsistent state, such as with a resolution of 'closed', but with a status of 'accepted'. This needs to be addressed.
  Seems to be addressed now (`_check_for_resolution` / `_remove_resolution_if_not_closed`)


== Integration in Trac

While not all of the above requirements are yet dealt with in the plugin, the user interface from version 0.7 looks good enough to me to be a worthwhile addition to the core (cboos).

Further improvements can be done later on that basis. I'd like to see a 0.13 branch of Trac (use our git or hg [SubversionRepository#Mirrors mirrors]), with the batchmod plugin integrated in the trac/ticket subsystem (perhaps directly inside query.py).

A few ideas:
  - looks like there are tabs in the .css and .html files; other "usual" [TracDev/CodingStyle coding style] cleanups are needed in the .py code as well
  - seems there are lots of duplication in batchmod.js (from query.js);
  - the `ITemplateProvider`, `IRequestFilter`, `ITemplateStreamFilter` methods will no longer be needed
  - I don't see a real need for a separate `BatchModifier` class, this can be merged in the `BatchModifyModule` (it's still interesting to keep that individual module, though, so one can choose to disable it completely)
  - For the form processing, why not target a new URL (e.g. "/batchmodify"), so that you could have the `BatchModifyModule` be a real `IRequestHandler` (merge the current `BatchModifyModule.pre_process_request` and `BatchModifier.process_request` into a new `BatchModifyModule.process_request`)
   - there should be **one** transaction for all the ticket modifications, not one per ticket change!
  - For preparing the form data (the bits currently in `BatchModifyModule._generate_form`), this could be done in the `QueryModule` if the `BatchModifyModule` component is enabled
   - same thing for the conditional inclusion of the `batchmod.html` template from the `query.html` one