Versions: keep type of version in sync with the project

So, there are a couple of problems here:

- Versions have been created with the type set as unknown,
  and where never updated to the correct type.
  I was able to track down this to projects created before 2018,
  so probably an old bug allowed this to happen.
- Stable machine versions are basically an alias for the latest stable version
  of the project, and they can be a branch or a tag,
  this means that if this version is a branch,
  so will be the "stable" version, same for tags.
  Currently, we aren't updating the version type,
  if the stable version was created as a branch,
  it will remain as a branch, even if the latest stable version
  is a tag, and vice versa.
- Latest machine versions are basically an alias for the default branch
  of the project, they are always branches.
  Since we allow to have non-machine latest versions,
  they can be a branch or a tag. If this version was changed
  back to be a non-machine version, currently it will remain as branch
  or tag, this was incorrect.

Our new clone/checkout pattern relies on the type of the version always
being correct, so it was failing for some projects.

- Fixes #10600
- Fixes #10601

After deploy, we need to clean up the invalid versions (versions with
"unknown" type). We can do that by:

- Updating all latest machine versions to be branches.

  ```python
  Version.objects.filter(type="unknown", machine=True).update(type="branch")
  ```

- Re-evaluate the stable version of all projects that have a machine
  stable version, so they can have the correct type.

  ```
  for project in Project.objects.filter(versions__machine=True).distinct():
      project.update_stable_version()
  ```

- Check all remaining active versions with "unknown" type, and update them to
  be branches or tags (324). We can use a simple regex to see the
  version identifier looks like a commit.

  ```python
  vesions = Version.objects.filter(type="unknown", active=True)
  commit_regex = re.compile(r"^([a-f0-9]{40})|([a-f0-9]{7})$")
  for version in versions:
      if commit_regex.match(version.identifier):
          version.type = "tag"
      else:
          version.type = "branch"
      version.save()
  ```

Author: stsewd

readthedocs/api/v2/utils.py

@@ -117,6 +117,8 @@ def sync_versions_to_db(project, versions, type):  # pylint: disable=redefined-b
             latest_version.machine = True
             latest_version.identifier = project.get_default_branch()
             latest_version.verbose_name = LATEST_VERBOSE_NAME
+            # The machine created latest version always points to a branch.
+            latest_version.type = BRANCH
             latest_version.save()
     if added:
         log.info(

readthedocs/projects/models.py

@@ -1199,18 +1199,19 @@ def update_stable_version(self):
         new_stable = determine_stable_version(versions)
         if new_stable:
             if current_stable:
-                identifier_updated = (
+                version_updated = (
                     new_stable.identifier != current_stable.identifier
+                    or new_stable.type != current_stable.type
                 )
-                if identifier_updated:
+                if version_updated:
                     log.info(
-                        'Update stable version: %(project)s:%(version)s',
-                        {
-                            'project': self.slug,
-                            'version': new_stable.identifier,
-                        }
+                        "Stable version updated.",
+                        project_slug=self.slug,
+                        version_identifier=new_stable.identifier,
+                        version_type=new_stable.type,
                     )
                     current_stable.identifier = new_stable.identifier
+                    current_stable.type = new_stable.type
                     current_stable.save()
                     return new_stable
             else: