[BUG] rake db:create and observers
Reported by Ian White | April 29th, 2008 @ 07:29 PM
If you have an observer, then doing rake db:create in some circumstances (one is described below) causes rail to die with 'unknown database'.
Obviously a circular dependency problem.
I've been poking around the test suite, and can't seem to find the right place for testing this, can anyone offer any pointers?
The problem can be reproduced with (fresh rails app, with dbs wiped)
config/environment.rb:
config.active_record.observers = :user_observer
app/models/user.rb
class User < ActiveRecord::Base
has_many :posts, :conditions => ['posts.published = ?', true], :order => 'updated_at DESC', :dependent => :destroy
end
app/models/user_observer.rb
class UserObserver < ActiveRecord::Observer
end
Comments and changes to this ticket
-
-
Michael Koziarski May 4th, 2008 @ 01:47 AM
- → Assigned user changed from “” to “Michael Koziarski”
-
Ian White May 4th, 2008 @ 09:39 AM
Stack trace below
I've attached a git diff of what I had to add to a fresh rails app (6a6b439 Sun Apr 20 12:57:36 2008 +0800) to get the problem to occur.
I'd be happy to investigate, but couldn't find the obvious place to start adding tests.
~/dev/sandbox/ticket63(master)$ rake db:create --trace (in /Users/ian/dev/sandbox/ticket63) ** Invoke db:create (first_time) ** Invoke environment (first_time) ** Execute environment rake aborted! Unknown database 'ticket63_development' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb:505:in `real_connect' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb:505:in `connect' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb:183:in `initialize' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb:88:in `new' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb:88:in `mysql_connection' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb:292:in `send' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb:292:in `connection=' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb:260:in `retrieve_connection' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb:78:in `connection' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/base.rb:2067:in `quote_bound_value' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/base.rb:2035:in `replace_bind_variables' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/base.rb:2035:in `gsub' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/base.rb:2035:in `replace_bind_variables' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/base.rb:2024:in `sanitize_sql_array' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/base.rb:1921:in `sanitize_sql' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/associations.rb:1249:in `configure_dependency_for_has_many' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/associations.rb:700:in `has_many' /Users/ian/dev/sandbox/ticket63/app/models/user.rb:2 /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:214:in `load_without_new_constant_marking' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:214:in `load_file' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:353:in `new_constants_in' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:213:in `load_file' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:94:in `require_or_load' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:259:in `load_missing_constant' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:466:in `const_missing' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:478:in `const_missing' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/inflector.rb:271:in `constantize' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/core_ext/string/inflections.rb:143:in `constantize' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/observer.rb:157:in `observed_class' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/observer.rb:183:in `observed_classes' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/observer.rb:166:in `initialize' /opt/local/lib/ruby/1.8/singleton.rb:95:in `new' /opt/local/lib/ruby/1.8/singleton.rb:95:in `instance' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/observer.rb:38:in `instantiate_observers' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/observer.rb:36:in `each' /Users/ian/dev/sandbox/ticket63/vendor/rails/activerecord/lib/active_record/observer.rb:36:in `instantiate_observers' /Users/ian/dev/sandbox/ticket63/vendor/rails/actionpack/lib/action_controller/dispatcher.rb:26:in `define_dispatcher_callbacks' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/callbacks.rb:177:in `call' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/callbacks.rb:177:in `evaluate_method' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/callbacks.rb:161:in `call' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/callbacks.rb:90:in `run' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/callbacks.rb:90:in `each' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/callbacks.rb:90:in `send' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/callbacks.rb:90:in `run' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/callbacks.rb:272:in `run_callbacks' /Users/ian/dev/sandbox/ticket63/config/../vendor/rails/railties/lib/initializer.rb:460:in `send' /Users/ian/dev/sandbox/ticket63/config/../vendor/rails/railties/lib/initializer.rb:460:in `prepare_dispatcher' /Users/ian/dev/sandbox/ticket63/config/../vendor/rails/railties/lib/initializer.rb:146:in `process' /Users/ian/dev/sandbox/ticket63/config/../vendor/rails/railties/lib/initializer.rb:89:in `send' /Users/ian/dev/sandbox/ticket63/config/../vendor/rails/railties/lib/initializer.rb:89:in `run' /Users/ian/dev/sandbox/ticket63/config/environment.rb:13 /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require' /opt/local/lib/ruby/vendor_ruby/1.8/rubygems/custom_require.rb:27:in `require' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:508:in `require' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:353:in `new_constants_in' /Users/ian/dev/sandbox/ticket63/vendor/rails/activesupport/lib/active_support/dependencies.rb:508:in `require' /Users/ian/dev/sandbox/ticket63/vendor/rails/railties/lib/tasks/misc.rake:3 /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:546:in `call' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:546:in `execute' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:541:in `each' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:541:in `execute' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:508:in `invoke_with_call_chain' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:501:in `synchronize' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:501:in `invoke_with_call_chain' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:518:in `invoke_prerequisites' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1183:in `each' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1183:in `send' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1183:in `each' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:515:in `invoke_prerequisites' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:507:in `invoke_with_call_chain' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:501:in `synchronize' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:501:in `invoke_with_call_chain' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:494:in `invoke' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1931:in `invoke_task' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1909:in `top_level' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1909:in `each' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1909:in `top_level' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1948:in `standard_exception_handling' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1903:in `top_level' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1881:in `run' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1948:in `standard_exception_handling' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/lib/rake.rb:1878:in `run' /opt/local/lib/ruby/gems/1.8/gems/rake-0.8.1/bin/rake:31 /opt/local/bin/rake:16:in `load' /opt/local/bin/rake:16 -
Michael Koziarski May 4th, 2008 @ 09:44 AM
So it's trying to generate the finder sql for your has_many association, and needs the database connection in order to quote the sql,
I'm not sure how easy this will be to patch, don't worry about the tests initially, try to figure out the solution ;)
-
Ian White May 4th, 2008 @ 10:09 AM
Well, a really trivial 'fix' is to just rescue observer instantiation, and log the error (patch given on right)
Given that this is a bootstrapping dependency problem, this might be appropraite. It's a bit icky though.
A more sophisticated version of this approach would be to have a config setting 'allow_observer_instatiation_failure', which is set by various bootstrapping tasks (like db:create, or db:migrate). Also, being more discriminating on error catching would be useful.
Could you advise on whether this general approach (ignore snafus when bootstrapping) is likely to get traction? It could hide sins if used badly. It would be in effect saying 'bootstrapping is different to running the app'
-
Ian White May 4th, 2008 @ 10:20 AM
Even simpler: rescue the bootstrapping tasks' db loading
Given that this is an edge case (trying to load up framework when db
doesn't yet exist), it makes sense to allow for snafus that result
from this.
-
Joshua Peek July 17th, 2008 @ 01:08 AM
- → Tag changed from “” to “activerecord bug”
- → State changed from “new” to “open”
Koz, you going apply this?
-
Gerrit Kaiser October 6th, 2008 @ 01:52 AM
This one trips me up a lot aswell. Pretty much makes db:create and co unusable for me (I’m heavily using branch-specific databases so have a need to create them even after the initial app generation).
I don’t really see why db:create would depend on the whole environment at all… Couldn’t it just load the database.yml and use ActiveRecord independent of the app? That would reduce the startup time for those tasks aswell.
-
Michael Koziarski October 6th, 2008 @ 01:05 PM
That sounds like a much nicer fix, if you can make those tasks just read the yml file, (and some how know the RAILS_ENV) then we solve most of these issues.
-
Gerrit Kaiser October 22nd, 2008 @ 05:22 AM
- → Tag changed from “activerecord bug” to “activerecord bug create_database databases.rake patch rake”
whipped up a patch against a03e2b356c66ddc8809fa2b23a2a7d652f173b8b that won’t load the full environment for db:create:* and db:drop but instead just performs the minium config loading necessary.
successfully manually tested on a skeleton rails app (didn’t see any examples of how to automatically test rake tasks)
-
Aliaksey Kandratsenka November 28th, 2008 @ 03:41 PM
After Gerrit's patch db:drop stopped working for mysql. That's because mysql connection wasn't established before call to #drop_database. I'm attaching a trivial fix.
-
Aliaksey Kandratsenka November 28th, 2008 @ 03:42 PM
Ah. I forgot to mention that Gerrit's patch fixed the problem for us.
-
Repository December 1st, 2008 @ 08:40 PM
- → State changed from “open” to “committed”
(from [a0bc480e1ddcaa015927c2d941e7b96a8ce4f6fa]) establish mysql connection before dropping database
Signed-off-by: Michael Koziarski michael@koziarski.com [#63 state:committed] http://github.com/rails/rails/co...
Please Login or create a free account to add a new comment.
You can update this ticket by sending an email to from your email client. (help)
Create your profile
Help contribute to this project by taking a few moments to create your personal profile. Create your profile »
Source available from github
Repository is at http://github.com/rails/rails
Check out the development master (Edge Rails):
git clone git://github.com/rails/rails.git
Creating or reviewing a patch
See the contributor guide.
Creating a feature request
Please don't. If you want a new feature in Rails, you'll have to pull up your sleeves and get busy yourself. Or convince someone else to do it. See the contributor guide on how to get going. But posting them here is just going to lead to ticket root.
Creating a bug report
When creating a bug report, be sure to include as much relevant information as possible. Post the code sample that causes the problem. Preferably, alter the unit tests and show through either changed or added tests how the expected behavior is not occuring.
Security vulnerabilities should be reported via an email to security@rubyonrails.org, do not use trac for reporting security vulnerabilities. All content in trac is publicly available as soon as it is posted.
Then don't get your hopes up. Unless you have a "Code Red, Mission Critical, The World is Coming to an End" kinda bug, you're creating this ticket in the hope that others with the same problem will be able to collaborate with you on solving it. Do not expect that the ticket automatically will see any activity or that others will jump to fix it. Creating a ticket like this is mostly to help yourself start on the path of fixing the problem and for others to sign on to with a "I'm having this problem too"..
Rob Sanheim
Pastor Zack Hubert
Adam Cigánek