[cfe-dev] [llvm-dev] RFC: Switching from Bugzilla to Github Issues [UPDATED]

[Fangrui Song via cfe-dev]

On 2020-04-20, Richard Smith via cfe-dev wrote:
>On Mon, 20 Apr 2020 at 13:57, Anton Korobeynikov via cfe-dev <
>cfe-dev at lists.llvm.org> wrote:
>
>> > If we are reasonably certain that no one would be opening new issues on
>> GitHub while the migration is running...
>> And pull requests (the numbering is common for issues and pull
>> requests) as well. And we cannot disable pull requests at all. And I'm
>> afraid the issues will need to be opened as well during the migration.
>> And now the real problem: should an "extra" pull request or issue
>> intervene in the migration there is no way to "reset" the counter
>> besides deleting the project and creating it once again. We could only
>> sacrifice some bugzilla issues to restore the numbering...
>>
>
>We can edit summaries and comments, presumably by API calls as well as by
>the web UI. So how about this:
>
>Step 1: Preallocate sufficient github issue numbers. Make a bot account and
>with it file empty placeholder issues until we have N issues total, where N
>is the number of bugzilla bugs.
>Step 2: Shut down the ability to file new bugzilla bugs, double-check we
>have enough placeholder bugs, then open up github for new issue
>submissions. Change llvm.org/PRxxxxx to redirect to github for xxxxx's
>higher than the transition point.
>Step 3a: For each issue filed by the bot account, sync that bug's contents
>to the bugzilla entry: copy across the subject, all the comments, tags, and
>so on.
>Step 3b: For each issue not filed by the bot account whose number is that
>of a bugzilla entry, file a new github bug and sync it with the bugzilla
>bug then add a tracking comment to the github bug saying what the new
>number is.
>
>All we would need to do before we switch systems is steps 1 and 2. The data
>import can be done incrementally with no time constraints. Once transition
>is complete, we can change llvm.org/PRxxxxx (and existing bugzilla links,
>since I'm sure they exist in the wild too) to redirect to github, and shut
>down our bugzilla instance.
>
>If new PRs are filed during step 1, we get new "problem" issue numbers,
>which we deal with in the same way as the 210 existing github issue numbers.

Not sure about the API throttling, ideally we can create a new
repository, write a script and allocate a github issue X for each
bugzilla issue X in some repository. We can then gradually copy comments
to that repository.

After contents are migrated, add a redirector llvm.org/PRxxxxx -> https://github.com/llvm/some-repository/issue/xxxxx