4.2.0: Support Rails 8.1

[afeng-mdsol]

@mdsol/platform-scalability

policy_machine.gemspec:

Widened activerecord dependency from ~> 7.1 to ~> 8.1

Widened rails dev dependency from ~> 7.1 to ~> 8.1
Removed deprecated s.test_files accessor
active_record.rb:

db_config: Removed legacy code paths for ActiveRecord < 6.0 and == 6.0; now uses the standard configs_for(env_name:, name:) + configuration_hash API
connection_db_config: Removed connection_config fallback (removed in Rails 7.1)
serialize: Fixed to use coder: keyword argument (active_record_serialize store, coder: serializer) as required by Rails 8.0+ (positional serializer argument was removed)
postgres?: Changed from ::ActiveRecord::Base.connection.class.name check to ::ActiveRecord::Base.connection_db_config.adapter == 'postgresql' (avoids deprecated ActiveRecord::Base.connection call)
postgresql.rb:

Replaced 3 uses of deprecated sanitize_sql_for_conditions with sanitize_sql
mysql2.rb:

Removed attr_accessible (removed from Rails since 4.0)
Fixed remove_from_transitive_closure to use .rows.flatten instead of .to_a for connection.execute results (compatible with ActiveRecord::Result returned in Rails 8.1)
active_record_spec.rb:

Changed ActiveRecord::Base.connection.execute to avoid deprecated bare ActiveRecord::Base.connection call
version.rb: Bumped to 4.2.0

CHANGELOG.md: Documented all changes

Relates to: https://github.com/mdsol/dalton/pull/5755

[afeng-mdsol]

ActiveRecord::InvalidMigrationTimestampError:  (ActiveRecord::InvalidMigrationTimestampError)

Invalid timestamp 99999999999999 for migration file: add_test_columns.
Timestamp must be in form YYYYMMDDHHMMSS, and less than 20260624162521.

when setting up the test db to run specs

[Copilot]

Pull request overview

Updates the gem to be compatible with Rails/ActiveRecord 8.1 by removing/avoiding deprecated APIs, updating adapter behavior for changed return types, and documenting the release.

Changes:

• Updated ActiveRecord adapter internals (config lookup, serialization API usage, postgres detection) for Rails 8.1.
• Updated SQL sanitization calls in the PostgreSQL adapter and transitive-closure maintenance in the MySQL2 adapter for Rails 8.1 behavior.
• Bumped gem dependencies/version and added release notes + Backstage component metadata.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
test/tasks/setup.rake	Updates test-app setup to copy a specific migration filename
spec/policy_machine_storage_adapters/active_record_spec.rb	Avoids deprecated ActiveRecord::Base.connection usage in a spec
policy_machine.gemspec	Bumps ActiveRecord/Rails dependency requirements
lib/policy_machine/version.rb	Version bump for the release
lib/policy_machine_storage_adapters/active_record/postgresql.rb	Replaces deprecated SQL sanitization helper usage
lib/policy_machine_storage_adapters/active_record/mysql2.rb	Removes deprecated attr_accessible and adjusts execute-result handling
lib/policy_machine_storage_adapters/active_record.rb	Removes legacy AR branches; updates serialization + postgres detection
factbook.yaml	Adds Backstage component metadata
CHANGELOG.md	Adds 4.2.0 release notes

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[etmilord-3ds]

LGTM 👍

[etmilord-3ds]

Just curious, why did this need to be changed?

[chchan-mdsol]

ActiveRecord::Base.connection_config was deprecated sometime after Rails 6.1.
rails/rails#38005

[wdutymdsol]

LOL, just amused. 😄