Hi, it’s Vipul. Let’s explore this week’s changes in the Rails codebase.

Active Support Instrumentation Documentation
This Pull Request updates the Active Support Instrumentation documentation to receive various additions, improvements and more. It is now open for review and feedback from the community!

Ensure TimeWithZone#as_json always returns a UTF-8 string
This PR addresses a regression in Rails 8.1.0 where ActiveSupport::TimeWithZone#as_json was returning strings with incorrect encoding. Since Time#xmlschema returns a US-ASCII encoded string, as_json was returning US-ASCII instead of UTF-8. The fix ensures that the JSON representation always returns a properly encoded UTF-8 string.

Handle closed PostgreSQL connections in retryable_query_error?
When a PostgreSQL connection dies unexpectedly, retryable_query_error? calls @raw_connection.transaction_status, which raises PG::ConnectionBad on a closed connection. The PostgreSQL adapter’s retryable_query_error? previously handled two scenarios: when the connection is nil or when it’s alive. This PR adds handling for a third case where the connection object exists but is closed, by rescuing PG::ConnectionBad and allowing the retry logic to proceed appropriately.

Handle asynchronous raise in all of reconnect!
Three operations—reconnect, reset_transaction, and clear_cache—could take considerable time and remain susceptible to TimeoutError exceptions, potentially corrupting connection state. This change extends the exception-handling approach to fully encompass the entire reconnect! method.

Ensure variants are loaded and processed synchronously just once
A fix has been introduced to avoid reprocessing variants during preview redirects. Previously, when generating a preview (e.g., for PDFs or videos), Active Storage would create the variant on the primary database, but a second lookup happened on a read replica before replication caught up — causing unnecessary reprocessing and failures. The change ensures the same variant instance is reused within the request, preventing redundant database queries and variant creation errors.

Fix TimeWithZone#xmlschema when wrapping DateTime local time ActiveSupport::TimeWithZone#xmlschema was producing invalid ISO-8601 strings when instantiated with a DateTime used as local time. The implementation incorrectly assumed that time.iso8601 always ends with "Z".

tz  = ActiveSupport::TimeZone["America/New_York"]
twz = ActiveSupport::TimeWithZone.new(nil, tz, DateTime.new(2025, 11, 7, 12))

twz.xmlschema
# Before
"2025-11-07T12:00:00+00:0-05:00" # invalid

# After
"2025-11-07T12:00:00-05:00" # correct

The fix updates the method to replace the entire timezone suffix (whether Z or ±HH:MM) instead of just the final character, ensuring correct timezone offset calculation for both Time and DateTime instances.

Fix CI eager loading when rake tasks invoke :environment before tests
The test environment sets config.eager_load = ENV["CI"].present? to enable eager loading in CI and catch autoloading bugs. However, when gems invoke the :environment rake task before tests run, Rails overrides this setting with config.rake_eager_load (which defaults to false), disabling eager loading in CI. This PR adds config.rake_eager_load = ENV["CI"].present? to the generated test environment configuration, ensuring eager loading behavior remains consistent in CI regardless of whether rake tasks trigger the :environment hook.

QueryIntent#execute!
This PR introduces QueryIntent#execute! to improve Active Record’s internal query execution architecture. Previously, query intents were passive containers passed through the system, but now they can actively execute queries and store results. This refactoring makes QueryIntent instances self-sufficient. They know which adapter they belong to and can ask the adapter to do work like query preprocessing. The change streamlines the query execution flow and sets the foundation for better handling of query results in different formats (raw or cast).

You can view the whole list of changes here. We had 15 contributors to the Rails codebase this past week!

Until next time!

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