Heroku precompile assets failed on Rail 4 app

Question

I set

config.assets.initialize_on_precompile = false

in the application.rb. Assets were precompiled successfully locally by run

RAILS_ENV=production bundle exec rake assets:precompile

While the manifest-fingerprint.json(Rails 4.0 generates manifest.json instead of manifest.yml) was not detected when pushed to Heroku and Heroku tried to run precompile again. Then I got the error as:

Running: rake assets:precompile
       rake aborted!
       could not connect to server: Connection refused
       Is the server running on host "127.0.0.1" and accepting
       TCP/IP connections on port 5432?
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/postgresql_adapter.rb:771:in `initialize'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/postgresql_adapter.rb:771:in `new'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/postgresql_adapter.rb:771:in `connect'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/postgresql_adapter.rb:493:in `initialize'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/postgresql_adapter.rb:41:in `new'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/postgresql_adapter.rb:41:in `postgresql_connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/abstract/connection_pool.rb:446:in `new_connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/abstract/connection_pool.rb:456:in `checkout_new_connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/abstract/connection_pool.rb:427:in `acquire_connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/abstract/connection_pool.rb:364:in `block in checkout'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/abstract/connection_pool.rb:363:in `checkout'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/abstract/connection_pool.rb:273:in `block in connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/abstract/connection_pool.rb:272:in `connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_adapters/abstract/connection_pool.rb:552:in `retrieve_connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_handling.rb:79:in `retrieve_connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/connection_handling.rb:53:in `connection'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/model_schema.rb:208:in `columns'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/model_schema.rb:242:in `column_defaults'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/locking/optimistic.rb:169:in `column_defaults'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/core.rb:164:in `initialize'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/inheritance.rb:24:in `new'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activerecord-4.0.0.beta1/lib/active_record/inheritance.rb:24:in `new'
       /tmp/build_2ospgf61r6sch/lib/student_module.rb:11:in `acts_as_student'
       /tmp/build_2ospgf61r6sch/app/models/applicant.rb:4:in `<class:Applicant>'
       /tmp/build_2ospgf61r6sch/app/models/applicant.rb:3:in `<top (required)>'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:228:in `require'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:228:in `block in require'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:213:in `load_dependency'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:228:in `require'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:329:in `require_or_load'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:288:in `depend_on'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:206:in `require_dependency'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/engine.rb:464:in `block (2 levels) in eager_load!'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/engine.rb:463:in `each'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/engine.rb:463:in `block in eager_load!'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/engine.rb:461:in `each'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/engine.rb:461:in `eager_load!'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/engine.rb:346:in `eager_load!'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/application/finisher.rb:56:in `each'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/application/finisher.rb:56:in `block in <module:Finisher>'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/initializable.rb:30:in `instance_exec'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/initializable.rb:30:in `run'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/initializable.rb:55:in `block in run_initializers'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/initializable.rb:54:in `run_initializers'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/application.rb:213:in `initialize!'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/railtie/configurable.rb:30:in `method_missing'
       /tmp/build_2ospgf61r6sch/config/environment.rb:5:in `<top (required)>'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:228:in `require'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:228:in `block in require'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:213:in `load_dependency'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/activesupport-4.0.0.beta1/lib/active_support/dependencies.rb:228:in `require'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/application.rb:187:in `require_environment!'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/railties-4.0.0.beta1/lib/rails/application.rb:247:in `block in run_tasks_blocks'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:246:in `call'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:246:in `block in execute'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:241:in `each'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:241:in `execute'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:184:in `block in invoke_with_call_chain'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:177:in `invoke_with_call_chain'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:170:in `invoke'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/sprockets-rails-2.0.0.rc4/lib/sprockets/rails/task.rb:16:in `block (2 levels) in define'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:246:in `call'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:246:in `block in execute'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:241:in `each'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:241:in `execute'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:184:in `block in invoke_with_call_chain'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:177:in `invoke_with_call_chain'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:205:in `block in invoke_prerequisites'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:203:in `each'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:203:in `invoke_prerequisites'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:183:in `block in invoke_with_call_chain'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:177:in `invoke_with_call_chain'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/task.rb:170:in `invoke'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:143:in `invoke_task'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:101:in `block (2 levels) in top_level'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:101:in `each'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:101:in `block in top_level'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:110:in `run_with_threads'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:95:in `top_level'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:73:in `block in run'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:160:in `standard_exception_handling'
       /tmp/build_2ospgf61r6sch/vendor/bundle/ruby/2.0.0/gems/rake-10.0.4/lib/rake/application.rb:70:in `run'

Seems the error was due to the file in the lib/student_module.rb, which was required in config/initializers/student_init.rb:

#lib/student_module.rb, the error pointed to this line：
user_attributes = User.new.abttributes.keys
#config/initializers/student_init.rb
require 'student_module'
ActiveRecord::Base.extend Student

The error could be because Heroku initializes the app, which includes connection to the database. But I was not supposed to see the messages like

rake aborted!
could not connect to server: Connection refused
Is the server running on host "127.0.0.1" and accepting
TCP/IP connections on port 5432?

because I set config.assets.initialize_on_precompile false and also precompile the assets locally.

Any suggestions to solve this?Thanks!

score 22 · Accepted Answer · answered May 08 '13 at 07:25

22

You'll need to enable a labs feature on Heroku user-env-compile which gives the app access to the environment variables at compile time.

heroku labs:enable user-env-compile -a myapp

Read more about it at https://devcenter.heroku.com/articles/labs-user-env-compile

answered May 08 '13 at 07:25

John Beynon

37,398
8
88
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do you know why this fixes the problem? This seems like a quick fix the violates Heroku best practices. – corbin Oct 29 '13 at 22:35
2

Yeah, it does - it means that the build is dependent on something defined outside the code which definitely violates 12factor. The problem is when there is code in your app that accesses the DB on initialisation it expects the DB to be there and causes the error - it's down to Gems/Frameworks to prevent this from occurring. – John Beynon Oct 30 '13 at 10:43

Heroku precompile assets failed on Rail 4 app

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