I have an engine, that has gem dependency. This gem has rake task to install migrations:
rake acts_as_taggable_on_engine:install:migrations
What is the proper way to install migration? When I run this command from host app or my engine I getting
Don't know how to build task
Add the gem dependency to you gemspec:
Gem::Specification.new do |s|
# ...
s.add_dependency 'acts-as-taggable-on', '~> 6.0'
# ...
end
Then require the gem in your engine:
# lib/my_engine/engine.rb
require 'acts-as-taggable-on'
module MyEngine
class Engine < ::Rails::Engine
isolate_namespace Chatty
end
end
ActsAsTaggableOn should be loaded through the main file which requires the engine as well unlike some gems where you require gemname/engine - and the file naming is not snake_case like most gems.
Then run bundle install and rake acts_as_taggable_on_engine:install:migrations in the folder of the dummy application (or the host).
max#MaxBook ~/p/c/t/dummy> rake acts_as_taggable_on_engine:install:migrations
Copied migration 20181030123059_acts_as_taggable_on_migration.acts_as_taggable_on_engine.rb from acts_as_taggable_on_engine
Copied migration 20181030123060_add_missing_unique_indices.acts_as_taggable_on_engine.rb from acts_as_taggable_on_engine
Copied migration 20181030123061_add_taggings_counter_cache_to_tags.acts_as_taggable_on_engine.rb from acts_as_taggable_on_engine
Copied migration 20181030123062_add_missing_taggable_index.acts_as_taggable_on_engine.rb from acts_as_taggable_on_engine
Copied migration 20181030123063_change_collation_for_tag_names.acts_as_taggable_on_engine.rb from acts_as_taggable_on_engine
Copied migration 20181030123064_add_missing_indexes_on_taggings.acts_as_taggable_on_engine.rb from acts_as_taggable_on_engine
I don't know why but invoking the command through bundler (bundle exec ...) does not work. This may give problems with RVM if you are using shims.
You can also create a generator for your engine that invokes the task:
# lib/generators/my_engine/install/install_generator.rb
module MyEngine
class InstallGenerator < Rails::Generators::Base
source_root File.expand_path('templates', __dir__)
desc "Installs MyEngine"
def copy_initializer
# template 'my_engine.rb', 'config/initializers/my_engine.rb'
rake "acts_as_taggable_on_engine:install:migrations"
end
end
end
Which you can then run with rails g my_engine:install.
Related
It's possible, for example, to use ActiveRecord inline in a Ruby script. I like this a lot to report bugs, test features and share gists.
I'm wondering if the same could be done for a Rails webservice? (I'm mainly interested in getting the controller layer to work, the rest should be easy to add on demand.) Something along these lines:
begin
require "bundler/inline"
rescue LoadError => e
$stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
raise e
end
gemfile(true) do
source "https://rubygems.org"
gem 'rails', '~> 6.0.0'
end
require 'rails/commands'
APP_PATH = File.expand_path('config/application', __dir__)
Rails::Command.invoke('server')
When toying around with this it did seem that an external entry point (APP_PATH) is required. So alternatively, an acceptable approach would be to cram all config into the single entry point. I couldn't get this to work so far.
The Rails Initialization Process is the best resource I found about this so far.
I produced a minimal Rails app to get started as follows:
rails new min-rails --skip-keeps --skip-action-mailer --skip-action-mailbox --skip-action-text --skip-active-record --skip-active-storage --skip-puma --skip-action-cable --skip-sprockets --skip-spring --skip-listen --skip-javascript --skip-turbolinks --skip-test --skip-system-test --skip-bootsnap --api
cd min-rails
rm -rf app/jobs app/models config/initializers config/locales lib log public tmp vendor config/environments/test.rb config/environments/production.rb config/credentials.yml.enc config/master.key bin/rake bin/setup bin/bundle
I ended up with the following script:
inline-rails.rb
begin
require "bundler/inline"
rescue LoadError => e
$stderr.puts "Bundler version 1.10 or later is required. Please update your Bundler"
raise e
end
gemfile(true) do
source "https://rubygems.org"
gem 'rails', '~> 6.0.0'
end
require "action_controller/railtie"
class App < Rails::Application
routes.append do
get "/hello/world" => "hello#world"
end
config.consider_all_requests_local = true # display errors
end
class HelloController < ActionController::API
def world
render json: {hello: :world}
end
end
App.initialize!
Rack::Server.new(app: App, Port: 3000).start
Run it as:
ruby inline-rails.rb
I know how to create a rails generator gem which is called like:
rails g my_generator command
And I know how to create a thor gem which can be called like:
my_generator command
But I don't know how to create a rails generator that can be called using an executable. I have tried by creating a lib/my_generator/cli.rb file like:
require 'thor'
module Mang
class Cli < Thor
include ::Rails::Generators::Base
desc "install_gem", "install a gem"
def install_gem
gem 'thor', "0.18.1"
end
end
end
But I get the following error despite having added Rails as a dependency in my gemspec.
uninitialized constant Rails (NameError)
The fix was just a matter of including the rails/generators/actions module.
require 'thor'
require 'rails/generators'
require 'rails/generators/actions'
module Mang
class Cli < Thor
include Thor::Actions
include Rails::Generators::Actions
desc "install_gem", "install a gem"
def install_gem
gem 'thor', "0.18.1"
end
end
end
I have a gem that I am making and it is located at the same level as a rails app.
I am trying to use the gem in the rails app, but am not able to make it work - the constant I am trying to use, which is defined in the gem, is not accessible to the rails app for some reason.
What am I doing wrong here? What steps can I take to begin debugging the cause of the problem?
In the rails console, $:.grep /mygem/ shows me ["/Users/zabba/mygem/lib"]
Directory structure, with the contents of certain files:
~/mygem/
lib/
mygem/
some_class.rb
module Mygem
class SomeClass
end
end
mygem.rb
require 'mygem/some_class'
~/railsapp/
Gemfile:
gem 'mygem', path: '../mygem', require: 'mygem'
app/
models/
a_model.rb:
# require 'mygem' cannot find file
class AModel
def hello_world
SomeClass.new # Cannot find constant
Mygem::SomeClass.new # Cannot find constant
end
end
Can you create a folder vendor/gems and copy your gem in there. Then in you Gemfile
Gemfile
gem 'mygem', :path => "vendor/gems/mygem-0.0.1"
Then bundle install
When I run test.rb (see below) as a separate ruby file from within my rails project it works fine but when I wrap it as a module to be called from a controller it gives me:
LoadError (no such file to load -- eventmachine):1 in 'ModuleTest'
The gem is installed (sudo gem install event machine and bundle install) and added to the gem file (gem 'eventmachine').
Could someone please advice on what it is that I'm missing?
Separate file (called through: $ ruby lib/test.rb):
require 'rubygems'
require 'eventmachine'
require 'em-http'
require 'fiber'
def doStuff
end
doStuff
Module:
require 'eventmachine'
require 'em-http'
require 'fiber'
module ModuleTest
def doStuff
end
end
Controller:
require 'moduletest'
class MyController < ApplicationController
doStuff
end
Add
gem 'eventmachine'
Into your Gemfile. Then execute bundle install.
If you want to use a new gem in your rails project, you need to add it into Gemfile. To learn more, visit http://gembundler.com/
gem install rubyoverflow
irb
> require 'rubyoverflow'
=> true
But:
require 'rubyoverflow'
include Rubyoverflow
class QuestionsController < ApplicationController
def question_by_tag
ruby_q = Questions.retrieve_by_tag('ruby')
Get error:
LoadError in
QuestionsController#question_by_tag no
such file to load -- rubyoverflow
Rails.root:
D:/artefacts/dev/projects/stack
app/controllers/questions_controller.rb:1:in
`'
This error occurred while loading the
following files: rubyoverflow
Is there any special rules to import moduled in the controller?
why do you use both require and include? include Rubyoverflow will be enough
UPD
For gem you should add it into your Gemfile (Rails 3.x) or config/environment.rb (Rails 2.x)
# Gemfile
gem "rubyoverflow"
# environment.rb
config.gem "rubyoverflow"
Then run bundle for Rails 3.x and rake gems:install for Rails 2.x