Ruby-on-rails – Do rails rake tasks provide access to ActiveRecord models

activerecordrakeruby-on-railstask

I am trying to create a custom rake task, but it seems I dont have access to my models. I thought this was something implicitly included with rails task.

I have the following code in lib/tasks/test.rake:

namespace :test do
  task :new_task do
    puts Parent.all.inspect
  end
end

And here is what my parent model looks like:

class Parent < ActiveRecord::Base
  has_many :children
end

It's a pretty simple example, but I get the following error:

/> rake test:new_task
(in /Users/arash/Documents/dev/soft_deletes)
rake aborted!
uninitialized constant Parent

(See full trace by running task with --trace)

Any ideas? Thanks

Best Answer

Figured it out, the task should look like:

namespace :test do
  task :new_task => :environment do
    puts Parent.all.inspect
  end
end

Notice the => :environment dependency added to the task

If you need the task to behave as a method, how about using an actual method?

task :build => [:some_other_tasks] do
  build
end

task :build_all do
  [:debug, :release].each { |t| build t }
end

def build(type = :debug)
  # ...
end

If you'd rather stick to `rake`'s idioms, here are your possibilities, compiled from past answers:

This always executes the task, but it doesn't execute its dependencies:
```
Rake::Task["build"].execute
```
This one executes the dependencies, but it only executes the task if it has not already been invoked:
```
Rake::Task["build"].invoke
```
This first resets the task's already_invoked state, allowing the task to then be executed again, dependencies and all:
```
Rake::Task["build"].reenable
Rake::Task["build"].invoke
```
Note that dependencies already invoked are not automatically re-executed unless they are re-enabled. In Rake >= 10.3.2, you can use the following to re-enable those as well:
```
Rake::Task["build"].all_prerequisite_tasks.each(&:reenable)
```

R – ActiveRecord models cached in rake tasks

The SQL cache isn't enabled per default for rake tasks. You can wrap your code in a cache block, like this:

task :foobar => :environment do
  ActiveRecord::Base.connection.cache do
    User.find 1 # Will hit the db
    User.find 1 # Will hit the cache
  end
end

This is essentially what Rails does for controller actions. Note that the cache uses memory and rake tasks has a tendency to work with large sets of data, which might give you issues. You can selectively opt-out of caching for parts of your code, using uncached

Best Answer

Related Solutions

Ruby – How to run Rake tasks from within Rake tasks

If you need the task to behave as a method, how about using an actual method?

If you'd rather stick to rake's idioms, here are your possibilities, compiled from past answers:

R – ActiveRecord models cached in rake tasks

Related Topic

If you'd rather stick to `rake`'s idioms, here are your possibilities, compiled from past answers: