In rails 5 created with `--api` I have an error 

    NoMethodError (undefined method `respond_to&#39; for #&lt;Api::MyController:0x005645c81f0798&gt;
    Did you mean?  respond_to?):


However, in the documentation for rails 4.2 it says http://edgeguides.rubyonrails.org/4_2_release_notes.html

&gt; respond_with and the corresponding class-level respond_to have been
&gt; moved to the responders gem. Add gem &#39;responders&#39;, &#39;~&gt; 2.0&#39; to your
&gt; Gemfile to use it:
&gt; 
&gt; 
&gt; Instance-level respond_to is unaffected:

And I&#39;m calling the instance method. What&#39;s the matter?



    class ApplicationController &lt; ActionController::API
    end
    
    # ...
    class Api::MyController &lt; ApplicationController
    
      def method1
        # ...
        respond_to do |format|
          format.xml { render(xml: &quot;fdsfds&quot;) }
          format.json { render(json: &quot;fdsfdsfd&quot; ) }
        end

Undefined instance method &quot;respond_to&quot; in Rails 5 API Controller

What is the difference between these two syntax:

`ENV.fetch(&quot;MY_VAR&quot;)`

`ENV[&#39;MY_VAR&#39;]`

I&#39;ve seen Rails 5 use both versions of these in difference places and can&#39;t figure out what the difference is (apart from the first one being more characters to type).

Rails: difference between ENV.fetch() and ENV[]

While I realize you are supposed to use a helper inside a view, I need a helper in my controller as I&#39;m building a JSON object to return.

It goes a little like this: 


    def xxxxx

       @comments = Array.new

       @c_comments.each do |comment|
       @comments &lt;&lt; {
         :id =&gt; comment.id,
         :content =&gt; html_format(comment.content)
       }
       end

       render :json =&gt; @comments
    end


How can I access my `html_format` helper?

Rails - How to use a Helper Inside a Controller

I&#39;ve upgraded one of my apps from Rails 4.2.6 to Rails 5.0.0. The [Upgrade Guide][1] says, that the Autoload feature is now disabled in production by default.

Now I always get an error on my production server since I load all lib files with autoload in the `application.rb` file.

    module MyApp
    	class Application &lt; Rails::Application
    		config.autoload_paths += %W( lib/ )
    	end
    end

For now, I&#39;ve set the `config.enable_dependency_loading` to `true` but I wonder if there is a better solution to this. There must be a reason that Autoloading is disabled in production by default.


  [1]: http://edgeguides.rubyonrails.org/upgrading_ruby_on_rails.html#autoloading-is-disabled-after-booting-in-the-production-environment

Rails 5: Load lib files in production

This code in rails 5

    class PagesController &lt; ApplicationController
      def action
        render nothing: true
      end
    end

results in the following deprecation warning

    DEPRECATION WARNING: :nothing` option is deprecated and will be removed in Rails 5.1. Use `head` method to respond with empty response body.

How do I fix this?

The &quot;:nothing&quot; option is deprecated and will be removed in Rails 5.1

How do you do an `or` query in **Rails 5** ActiveRecord? Also, is it possible to chain `or` with `where` in ActiveRecord queries?

Rails 5: ActiveRecord OR query

I&#39;m working with heroku and every time I try to push my app this message  shows out:

    remote: Compressing source files... done.
    remote: Building source:
    remote: 
    remote: -----&gt; Ruby app detected
    remote: 
    remote:  !
    remote:  !     You must use Bundler 2 or greater with this lockfile.
    remote:  !
    remote: /tmp/d20181109-104-g861yi/bundler-1.15.2/gems/bundler-1.15.2/lib/bundler/lockfile_parser.rb:108:in `warn_for_outdated_bundler_version&#39;: You must use Bundler 2 or greater with this lockfile. (Bundler::LockfileError)
    remote: 	from /tmp/d20181109-104-g861yi/bundler-1.15.2/gems/bundler-1.15.2/lib/bundler/lockfile_parser.rb:95:in `initialize&#39;
    remote: 	from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/helpers/bundler_wrapper.rb:130:in `new&#39;
    remote: 	from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/helpers/bundler_wrapper.rb:130:in `block in parse_gemfile_lock&#39;
    remote: 	from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/instrument.rb:18:in `block (2 levels) in instrument&#39;
    remote: 	from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/instrument.rb:40:in `yield_with_block_depth&#39;
    remote: 	from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/instrument.rb:17:in `block in instrument&#39;
    remote: 	from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/vendor/ruby/heroku-18/lib/ruby/2.5.0/benchmark.rb:308:in `realtime&#39;
    remote: 	from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/instrument.rb:16:in `instrument&#39;
    remote: 	from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/helpers/bundler_wrapper.rb:86:in `instrument&#39;
    remote:  !     Push rejected, failed to compile Ruby app.
    remote: 
    remote:  !     Push failed
    remote: Verifying deploy...
    remote: 
    remote: !	Push rejected to my-proyect-1234.
    remote: 

It says &#39;remote: ! You must use Bundler 2 or greater with this lockfile.&#39;

&gt; But my Bundler version is 2.0.0.pre.1

Don&#39;t know what to do, I tried uninstalling bundle and installing it again, I errased the Gemfile.lock and typing `bundle` again

Bundler: You must use Bundler 2 or greater with this lockfile

I am working with Rails 5

I aded new field username in model User.

    class Users::RegistrationsController &lt; Devise::RegistrationsController
      before_action :configure_permitted_parameters
      
      protected
      
      def configure_permitted_parameters
        devise_parameter_sanitizer.for(:sign_up).push(:username)  
      end
    end

During registration is displayed error: **undefined method `for&#39; for #&lt;Devise::ParameterSanitizer:0x007fc286b65ee0&gt; Did you mean? fork**


Trace:

NoMethodError (undefined method `for&#39; for #&lt;Devise::ParameterSanitizer:0x007fc286b65ee0&gt;
Did you mean?  fork):
  

    app/controllers/users/registrations_controller.rb:7:in `configure_permitted_parameters&#39;
      Rendering /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-5.0.0.rc1/lib/action_dispatch/middleware/templates/rescues/diagnostics.html.erb within rescues/layout
      Rendering /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-5.0.0.rc1/lib/action_dispatch/middleware/templates/rescues/_source.html.erb
      Rendered /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-5.0.0.rc1/lib/action_dispatch/middleware/templates/rescues/_source.html.erb (5.0ms)
      Rendering /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-5.0.0.rc1/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb
      Rendered /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-5.0.0.rc1/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (2.9ms)
      Rendering /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-5.0.0.rc1/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb
      Rendered /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-5.0.0.rc1/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb (1.2ms)
      Rendered /usr/local/rvm/gems/ruby-2.3.0/gems/actionpack-5.0.0.rc1/lib/action_dispatch/middleware/templates/rescues/diagnostics.html.erb within rescues/layout (118.1ms)

Who can help? How solve this problem?

Rails 5, Undefined method `for&#39; for #&lt;Devise on line devise_parameter_sanitizer.for

I&#39;ve tried to find some solution for this, but I really couldn&#39;t find anything related with the errors that is appearing to me when I run the rails command: 

&gt; rails generate model Book title:string summary:text isbn:string

   
    /home/vmu/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/activesupport-5.0.1/lib/active_support/xml_mini.rb:51: warning: constant ::Fixnum is deprecated
    /home/vmu/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/activesupport-5.0.1/lib/active_support/xml_mini.rb:52: warning: constant ::Bignum is deprecated
    /home/vmu/.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/activesupport-5.0.1/lib/active_support/core_ext/numeric/conversions.rb:138: warning: constant ::Fixnum is deprecated
    Running via Spring preloader in process 3579
    Expected string default value for &#39;--jbuilder&#39;; got true (boolean)
          invoke  active_record
       identical    db/migrate/20170104114702_create_books.rb
       identical    app/models/book.rb
          invoke    test_unit
       identical      test/models/book_test.rb
       identical      test/fixtures/books.yml

Anyone know what may be causing these errors?

warning: constant ::Fixnum is deprecated When generating new model

Turbolinks prevents normal `$(document).ready()` events from firing on all page visits besides the initial load, as discussed [here](https://stackoverflow.com/questions/18770517/rails-4-how-to-use-document-ready-with-turbo-links) and [here](https://stackoverflow.com/questions/18769109/rails-4-turbo-link-prevents-jquery-scripts-from-working/18770219#18770219). None of the solutions in the linked answers work with Rails 5, though. How can I run code on each page visit like in prior versions?

Rails 5: how to use $(document).ready() with turbo-links

I&#39;m new to rails. I noticed when generating data migration in rails 5, some people use `rails db:migrate` over `rake db:migrate`. Can someone explain the difference between the rails vs rake command in database migration? Does it mean rake command is obsolete in rails 5?

many thanks

rails db:migrate vs rake db:migrate

Rails 5.1 [removes a whole load of previously deprecated methods](https://blog.driftingruby.com/ruby-on-rails-5-1-0-deprecations/?utm_source=rubyweekly&amp;utm_medium=email). Among them is the old friend `render :text`.

It was very useful when you need to render _some_ text, but don&#39;t want the overhead of a view template. Examples:

    render text: &quot;ok&quot;
    render text: t(&#39;business_rules.project_access_denied&#39;), status: 401

What to use instead?


What to use instead of `render :text` (and `render nothing: true`) in rails 5.1 and later?

I am new to Rails 4, and do not understand the use of `secret_key_base` under `config/secrets.yml` in Rails 4. Can you please explain this concept?

Also, when I am working in the production environment, I am prompted to set the `secret_key` with `devise.rb`, `config.secret_key`, and `secret_key_base`. However, I can generate a new secret using the `rake secret` command. 

What is the difference between development and production environments?

How is it matching the newly generated `secret_key` when I add it with `secret_key_base` every time I generate?

How is it securing the application with other servers?

What is the use of secret_key_base in rails 4

I know there are 3 main notations for supplying arguments to the [`where`](http://api.rubyonrails.org/classes/ActiveRecord/QueryMethods.html#method-i-where) ActiveRecord method:

 1. Pure String
 2. Array
 3. Hash

Specifying `and` for the `where` method is straight forward:

&lt;!-- language: lang-ruby --&gt;

    # Pure String notation
    Person.where(&quot;name = &#39;Neil&#39; AND age = 27&quot;)

    # Array notation
    Person.where([&quot;name = ? AND age = ?&quot;, &#39;Neil&#39;, 27])

    # Hash notation
    Person.where({name: &quot;Neil&quot;, age: 27})

Specifying `or` for this same `where` method is stumping me for the hash syntax. Is it possible?

&lt;!-- language: lang-ruby --&gt;

    # Pure String notation
    Person.where(&quot;name = &#39;Neil&#39; OR age = 27&quot;)

    # Array notation
    Person.where([&quot;name = ? OR age = ?&quot;, &#39;Neil&#39;, 27])

    # Hash notation DOESN&#39;T WORK
    Person.where({name: &quot;Neil&quot; OR age: 27})

ActiveRecord OR query Hash notation

We know that Rails 5 added `ApplicationRecord` as an abstract class which was inherited by our models (ActiveRecord).

But basically, I think every technical requirement we do with ApplicationRecord, we can also do with `ActiveRecord::Base`. For instance:

    module MyFeatures
      def do_something
        puts &quot;Doing something&quot;
      end
    end
    
    class ApplicationRecord &lt; ActiveRecord::Base
      include MyFeatures
      self.abstract_class = true
    end

So now every model will be attached the behaviors of `MyFeatures`. But we can also achieve this in Rails 4:

    ActiveRecord::Base.include(MyFeatures)

So what is the benefit of using `ApplicationRecord`, do you think it is necessary to add `ApplicationRecord`?

Why Rails 5 uses ApplicationRecord instead of ActiveRecord::Base?

I have simple action show 

    def show
      @field = Field.find_by(params[:id])
    end

and i want write spec for it 

    require &#39;spec_helper&#39;
    
    RSpec.describe FieldsController, type: :controller do
    
        let(:field) { create(:field) }
    
      it &#39;should show field&#39; do
        get :show, id: field
        expect(response.status).to eq(200)
      end
    end


but I have got an error

    Failure/Error: get :show, id: field
     
     ArgumentError:
       unknown keyword: id

How to fix it?

Controller spec unknown keyword: id

After upgrading a Rails app to Rails 5, running RSpec tests gives me the following error:

    rails aborted!
    ActiveRecord::NoEnvironmentInSchemaError: 

    Environment data not found in the schema. To resolve this issue, run: 

	    bin/rails db:environment:set RAILS_ENV=test

However, that `bin` does not exist and I can&#39;t seem to generate it with `bundle binstubs rails` or with `rake rails:update:bin`.

I have also tried:
    
    rails db:environment:set RAILS_ENV=test
    rake db:environment:set RAILS_ENV=test

There is a related issue on Github [here](https://github.com/rails/rails/issues/23279).

How can I address this error?

Rails 5, Rspec: Environment data not found in the schema

I&#39;ve got an API mode Rails 5 app that won&#39;t let me run `rake routes` or `rails s`. The error I get is:

    $ rake routes
    rake aborted!
    LoadError: Could not load the &#39;listen&#39; gem. Add `gem &#39;listen&#39;` to the development group of your Gemfile
    .../config/environment.rb:5:in `&lt;top (required)&gt;&#39;
    LoadError: cannot load such file -- listen
    .../config/environment.rb:5:in `&lt;top (required)&gt;&#39;
    Tasks: TOP =&gt; routes =&gt; environment
    (See full trace by running task with --trace)

I&#39;ve verified that `listen` is in the development group in my Gemfile:

    group :development do
      gem &#39;listen&#39;, &#39;~&gt; 3.1.5&#39;
      # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
      gem &#39;spring&#39;
      gem &#39;spring-watcher-listen&#39;, &#39;~&gt; 2.0.0&#39;
    end

And that it&#39;s in my Gemfile.lock:

    $ cat Gemfile.lock | grep &#39;listen&#39;
        listen (3.1.5)
        spring-watcher-listen (2.0.0)
          listen (&gt;= 2.7, &lt; 4.0)
      listen (~&gt; 3.1.5)
      spring-watcher-listen (~&gt; 2.0.0)

I&#39;ve bundle updated, and bundle installed, and verified that `gem install listen` works. This was working earlier this week, but I&#39;m not having luck going back through my commits. 

    $ ruby -v
    ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-darwin14]

I don&#39;t see it in `vendor/cache` but I&#39;m not sure what to make of that...

    $ bundle package | grep &#39;listen&#39;

Appreciate the help!

**Update:**

I can &quot;fix&quot; the problem by putting `gem &#39;listen&#39;, &#39;~&gt; 3.1.5&#39;` in the global Gemfile (and removing it from `:development`). Then all the errors go away and everything works, but that seems wrong.


LoadError: Could not load the &#39;listen&#39; gem (Rails 5)

After `bundle update` my Rails app fails to boot with:

    Expected to find a manifest file in `app/assets/config/manifest.js` (Sprockets::Railtie::ManifestNeededError)

Why does Rails fails to boot with &quot;Expected to find a manifest file in `app/assets/config/manifest.js` (Sprockets::Railtie::ManifestNeededError)&quot;?

It&#39;s a constant headache when dealing with websockets, and it kills my performance in addition to adding bugs. Since ActionCable is the whole reason I upgraded I&#39;d very much like to get rid of it completely.

All Ruby on-Rails-5 Solutions on Gang of Coders

Total of 20 Ruby on-Rails-5 Solutions

Undefined instance method "respond_to" in Rails 5 API Controller