remove_column should only be used in the up (or change) step of a migration if
it's a post-deployment migration. Otherwise there will be downtime due to the
ActiveRecord column cache, which we can avoid by using the IgnorableColumn
concern in combination with a post-deployment migration.
- The migrations called `add_column_with_default` with a `null` option,
which the Rails `add_column` method accepts. This fails because
`add_column_with_default` expects an `allow_null` option instead.
- The migrations have been fixed to use `allow_null`.
1. Instantiate `ProtectedBranchesAccessSelect` from `dispatcher`
2. Use `can?(user, ...)` instead of `user.can?(...)`
3. Add `DOWNTIME` notes to all migrations added in !5081.
4. Add an explicit `down` method for migrations removing the
`developers_can_push` and `developers_can_merge` columns, ensuring that
the columns created (on rollback) have the appropriate defaults.
5. Remove duplicate CHANGELOG entries.
6. Blank lines after guard clauses.
1. Remove `master_or_greater?` and `developer_or_greater?` in favor of
`max_member_access`, which is a lot nicer.
2. Remove a number of instances of `include Gitlab::Database::MigrationHelpers`
in migrations that don't need this module. Also remove comments where
not necessary.
3. Remove duplicate entry in CHANGELOG.
4. Move `ProtectedBranchAccessSelect` from Coffeescript to ES6.
5. Split the `set_access_levels!` method in two - one each for `merge` and
`push` access levels.
1. Remove the `developers_can_push` and `developers_can_merge` boolean
columns.
2. Add two new tables, `protected_branches_push_access`, and
`protected_branches_merge_access`. Each row of these 'access' tables is
linked to a protected branch, and uses a `access_level` column to
figure out settings for the protected branch.
3. The `access_level` column is intended to be used with rails' `enum`,
with `:masters` at index 0 and `:developers` at index 1.
4. Doing it this way has a few advantages:
- Cleaner path to planned EE features where a protected branch is
accessible only by certain users or groups.
- Rails' `enum` doesn't allow a declaration like this due to the
duplicates. This approach doesn't have this problem.
enum can_be_pushed_by: [:masters, :developers]
enum can_be_merged_by: [:masters, :developers]
Jan Provaznik