How to set up a Rake task for seeding - ruby-on-rails

(This is really a newbie question about Rake & Rails & dependencies in general. Trying to wrap my head around how all this fits together)
Basically, I want a Rake task that acts like seed.rb but is called separately. It adds test data for the development environment, while my seed.rb provides basic data for all environments.
The script, family_seed.rb, uses FactoryGirl to generate some records. It looks like this:
require File.expand_path('../../config/environment', __FILE__)
require './spec/factories'
Family.delete_all
Member.delete_all
zinsser = Factory.create(:family, :last_name=>'Zinsser', :first_name=>'Carl', :sim_id => '500')
blackburn = Factory.create(:family, :last_name=>'Blackburn', :first_name=>'Greg', :sim_id => '501')
It runs fine with bundle exec "ruby db/family_seeds.rb", but my question is how to set it up with Rake. Should the whole thing be placed inside a Rake task? How could I, instead, set up a task that would call the script, while ensuring that the Rails development environment is available when it runs? I'm trying not just to get the job done, but to do it in a "right" way.

One way to approach this would be to create a class or module in lib (this makes it easier to write tests for, and makes the code more reusable):
require '../spec/factories'
class FamilySeed
def self.seed
raise "Don't run this in production!" if Rails.env.production?
Family.delete_all
Member.delete_all
zinsser = Factory.create(:family, :last_name=>'Zinsser', :first_name=>'Carl', :sim_id => '500')
blackburn = Factory.create(:family, :last_name=>'Blackburn', :first_name=>'Greg', :sim_id => '501')
end
end
How to create the rake task:
require 'family_seed'
namespace :seed do
task :families => :environment do
FamilySeed.seed
end
end
I'd be careful with allowing things like Family.delete_all and Member.delete_all to be too freely used. You could easily shoot yourself in the foot later on by calling something you didn't mean to on a production db.
How to run the rake task:
Run it in your command like with the following:
bundle exec rake seed:families

Create a rake task and require :environment
task :delete_all => :environement do
require Rails.root.join('spec/factories')
Family.delete_all
Member.delete_all
zinsser = Factory.create(:family, :last_name=>'Zinsser', :first_name=>'Carl', :sim_id => '500')
blackburn = Factory.create(:family, :last_name=>'Blackburn', :first_name=>'Greg', :sim_id => '501')
end
After you can run this task rake delete_all

Related

Rails dynamically create model and use it

I am creating a model whose name is the input argument in a rake task. After the rake task, I wish to use the model to insert data.
So for example, I call my rake task with input Apple and the model Apple is created. Then I wish to do Apple.insert_all([{name: x},{name: y}...]) in another rake task but I get NameError: uninitialized constant Apple
Here's a better picture of the flow of what I'm doing
Rake::Task["create:fruit"].invoke("Apple") # create model here
Rake::Task["create:insert"].invoke("Apple") # insert data here but getting error
This is how I process the input in the second rake task:
task :insert, [:name] do |t, args|
fruit = args.name
fruit.classify.constantize.insert_all(xxx)
end
Any suggestions for how to go about this?
I created a new project and tried your code. I think the problem is in this line
fruit.classify.constantize.insert_all(xxx)
The code bellow works and create new records. I use a simple rake command to run it.
create.rake file
namespace :create do
desc "TODO"
task :insert, [:name] do |t, args|
klass = Object.const_get(args.name)
klass.create([{name: 'x'},{name: 'y'}])
p klass.count # testing new records have been saved
end
end
Rakefile file
require File.expand_path('../config/application', __FILE__)
Rails.application.load_tasks
task :default do
Rake::Task["create:insert"].invoke("Apple")
end

How to fix "uninitialized constant" in a Rake task

I have a problem when I do:
namespace :xaaron do
task :get_roles do
roles = Xaaron::Role.all
puts roles
end
task :get_role, [:name] do |t, args|
role = Xaaron::Role.find(args[:name].parameterize)
puts role
end
end
The first task will work fine. I can even add binding.pry and run Xaaron::Role and get information about Roles back. But the second task fails with:
NameError: uninitialized constant Xaaron::Role
I run each task in my main app because these tasks are inside an engine, using:
bin/rake xaaron:get_roles` and `bin/rake xaaron:get_role
I can run bin/rails c in the main application that uses the engine and run Xaaron::Role and get information about Roles table.
Why is the second one failing but the first one is not? Is there scoping with arguments?
I'm not sure why either works, but if this is Rails and those are Rails models, your tasks should depend on the environment:
task :get_roles => [ :environment ] do
By depending on the :environment task, it first loads Rails.
Also see: What's the 'environment' task in Rake?.
You can also run a Rake task as
bundle exec rake environment xaaron:get_role
This will load the Rails environment first.
I kept getting uninitialized constant errors for a Rake task, even after depending on :environment and running with bundle exec.
The issue was that I was making a Rake::TestTask and, even though the Rake task had access to all constants, the test files themselves did not have access to constants.
The solution was to add this line to the top of my test file:
require_relative '../config/environment'
This is the Rake task:
require "rake/testtask"
Rake::TestTask.new(:test) do |t|
t.libs << "test"
t.libs << "lib"
t.test_files = FileList["test/**/test_*.rb"]
end
To add, as of Ruby 1.9 and above, you can use this hash syntax:
namespace :xaaron do
desc "Rake task to get roles"
task get_roles: :environment do
roles = Xaaron::Role.all
puts roles
end
#####
end
And then you can run the command below to run the Rake task:
rake xaaron:get_roles
or
bundle exec rake xaaron:get_roles

Changing a rake task to work on test environment

namespace :fixtures do
namespace :load do
task :prepare => :environment do
ENV['FIXTURES_PATH'] = "spec/fixtures"
ENV['RAILS_ENV'] ||= "test"
puts ENV.inspect
Rake::Task["db:fixtures:load"].invoke
end
end
end
I have added this to a special.rake file in ./lib/tasks in order to cause the rake db:fixtures:load command to apply to fixtures in the spec/fixtures directory, and to apply to the test environment.
It's not working. Where have I gone wrong?
You need to reconnect to the database. Something like
ActiveRecord::Base.establish_connection(ActiveRecord::Base.configurations["test"])
Changing ENV['RAILS_ENV'] after environment is already loaded doesn't do anything.
Perhaps it would also work if you load the environment task after you change ENV, but not sure about that:
task :prepare do
ENV['RAILS_ENV'] ||= "test"
Rake::Task["environment"].invoke
Rake::Task["db:fixtures:load"].invoke
end

How do I access one of my models from within a ruby script in the /lib/ folder in my Rails 3 app?

I tried putting my script in a class that inherited from my model, like so:
class ScriptName < MyModel
But when I ran rake my_script at the command-line, I got this error:
rake aborted!
uninitialized constant MyModel
What am I doing wrong?
Also, should I name my file my_script.rb or my_script.rake?
Just require the file. I do this in one of my rake tasks (which I name my_script.rake)
require "#{Rails.root.to_s}/app/models/my_model.rb"
Here's a full example
# lib/tasks/my_script.rake
require "#{Rails.root.to_s}/app/models/video.rb"
class Vid2 < Video
def self.say_hello
"Hello I am vid2"
end
end
namespace :stuff do
desc "hello"
task :hello => :environment do
puts "saying hello..."
puts Vid2.say_hello
puts "Finished!"
end
end
But a better design is to have the rake task simply call a helper method. The benefits are that it's easier to scan the available rake tasks, easier to debug, and the code the rake task runs becomes very testable. You could add a rake_helper_spec.rb file for example.
# /lib/rake_helper.rb
class Vid2 < Video
def self.say_hello
"Hello I am vid2"
end
end
# lib/tasks/myscript.rake
namespace :stuff do
desc "hello"
task :hello => :environment do
Vid2.say_hello
end
end
All I had to do to get this to work was put my requires above the task specification, and then just declare the :environment flag like so:
task :my_script => :environment do
#some code here
end
Just by doing that, gave me access to all my models. I didn't need to require 'active_record' or even require my model.
Just specified environment and all my models were accessible.
I was also having a problem with Nokogiri, all I did was removed it from the top of my file as a require and added it to my Gemfile.

How do I make Rake tasks run under my Sinantra app/environment?

I'm using Sinatra, and I wanted to set up some of the convenience rake tasks that Rails has, specifically rake db:seed.
My first pass was this:
namespace :db do
desc 'Load the seed data from db/seeds.rb'
task :seed do
seed_file = File.join(File.dirname(__FILE__), 'db', 'seeds.rb')
system("racksh < #{seed_file}")
end
end
racksh is a gem that mimics Rails' console. So I was just feeding the code in the seed file directly into it. It works, but it's obviously not ideal. What I'd like to do is create an environment task that allows commands to be run under the Sinanta app/environment, like so:
task :environment do
# what goes here?
end
task :seed => :environment do
seed_file = File.join(File.dirname(__FILE__), 'db', 'seeds.rb')
load(seed_file) if File.exist?(seed_file)
end
But what I can't figure out is how to set up the environment so the rake tasks can run under it. Any help would be much appreciated.
I've set up a Rakefile for Sinatra using a kind of Rails-like environment:
task :environment do
require File.expand_path(File.join(*%w[ config environment ]), File.dirname(__FILE__))
end
You then have something in config/environment.rb that contains what you need to start up your app properly. It might be something like:
require "rubygems"
require "bundler"
Bundler.setup
require 'sinatra'
Putting this set-up in a separate file avoids cluttering your Rakefile and can be used to launch your Sinatra app through config.ru if you use that:
require File.expand_path(File.join(*%w[ config environment ]), File.dirname(__FILE__))
run Sinatra::Application

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