Postgres error on Heroku with Resque

Question

I don't know enough Postgres to understand the message.

PG::Error: SSL error: decryption failed or bad record mac : SELECT a.attname, format_type(a.atttypid, a.atttypmod), d.adsrc, a.attnotnull FROM pg_attribute a LEFT JOIN pg_attrdef d ON a.attrelid = d.adrelid AND a.attnum = d.adnum WHERE a.attrelid = '"users"'::regclass AND a.attnum > 0 AND NOT a.attisdropped ORDER BY a.attnum

And here is the callstack got from the resque backend

/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/postgresql_adapter.rb:1139:in `async_exec'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/postgresql_adapter.rb:1139:in `exec_no_cache'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/postgresql_adapter.rb:663:in `block in exec_query'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/abstract_adapter.rb:280:in `block in log'
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.2/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/abstract_adapter.rb:275:in `log'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/postgresql_adapter.rb:662:in `exec_query'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/postgresql_adapter.rb:1264:in `column_definitions'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/postgresql_adapter.rb:858:in `columns'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/connection_adapters/schema_cache.rb:12:in `block in initialize'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/model_schema.rb:228:in `yield'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/model_schema.rb:228:in `default'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/model_schema.rb:228:in `columns'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/model_schema.rb:237:in `columns_hash'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/relation/delegation.rb:7:in `columns_hash'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/relation/finder_methods.rb:330:in `find_one'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/relation/finder_methods.rb:311:in `find_with_ids'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/relation/finder_methods.rb:107:in `find'
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.2/lib/active_record/querying.rb:5:in `find'
/app/app/workers/compute_worker.rb:5:in `perform'

Explanation: My worker is only doing some writing operations into the databases. Nothing complicated. When I execute the worker's task for the first time, it works, and the second time it fails with the above message. If I restart the worker, it will work only the first time. I already run

heroku pg:restart
heroku db:restart
heroku db:migrate

... without success.

On my local computer(using mysql) it works perfectly. Any idea ?

Answer 1

Thanks to the comments of "Rails beginner" and "mu is too short" I found the solution.

I've added this to an initializer and it did the trick!

Resque.after_fork = Proc.new { ActiveRecord::Base.establish_connection }

Answer 2

I had the same issue, but to solve it my app actually required a before_fork and not an after_fork. Hope this helps someone.

Resque.before_fork = Proc.new { ActiveRecord::Base.establish_connection }

Answer 3

This article from heroku explains how to properly connect and disconnect connections for resque:

Resque.before_fork do
  defined?(ActiveRecord::Base) and
    ActiveRecord::Base.connection.disconnect!
end

Resque.after_fork do
  defined?(ActiveRecord::Base) and
    ActiveRecord::Base.establish_connection
end

Answer 4

Resque.before_fork = Proc.new { 
     ActiveRecord::ActiveRecord::Base.verify_active_connections!
} 

would be even nicer