Cannot run any commands on my heroku app (migrate, console, etc)

Question

I am running rails 4.0.4 with ruby 2.1.1. app location: https://github.com/ravjohal/dozmia When I try to run commands on heroku, for instance: ``` ravjohal$ heroku run rake db:migrate ``` I get the following error: ``` Running `rake db:migrate` attached to terminal... up, run.2545 rake aborted! NoMethodError: undefined method `dump_schema_after_migration=' for ActiveRecord::Base:Class /app/vendor/bundle/ruby/2.1.0/gems/activerecord-4.0.4/lib/active_record/dynamic_matchers.rb:22:in `method_missing' /app/vendor/bundle/ruby/2.1.0/gems/activerecord-4.0.4/lib/active_record/railtie.rb:166:in `block (3 levels) in '...../app/config/environment.rb:5:in `'.... ``` here is part of the heroku logs: ``` /app/vendor/bundle/ruby/2.1.0/gems/activerecord-4.0.4/lib/active_record/dynamic_matchers.rb:22:in `method_missing': undefined method `dump_schema_after_migration=' for # (NoMethodError) 2014-03-27T18:30:55.729964+00:00 app[web.1]: from /app/ven…

Accepted Answer

The config `dump_schema_after_migration` didn't exist in Rails 4.0.4 .

You got the error because you deployed initially with Rails v4.1.0rc1 and switched over to v4.0.4 later. What really happened is that when you generated your app with rails 4.1.0rc, the generator put the config `dump_schema_after_migration` into your `config/environments/production.rb` and Rails 4.1.0rc1's code has this to support this config :

```
mattr_accessor :dump_schema_after_migration
```

Hence everything works fine in v4.1.0rc1. But when you moved back to v4.0.4, the config is still there in `config/environments/production.rb` , but the Rails code no longer knows how to read this config. To solve this, either stick with Rails 4.1.0rc1 code, or remove the config from `config/environments/production.rb` when running on Rails 4.0.4.

Btw, I added `dump_schema_after_migration` config to Rails code.

Cannot run any commands on my heroku app (migrate, console, etc)

Solution

Problem