You can get access to your models, and in fact, your whole environment by making tasks dependent on the environment task. This lets you do things like `run rake RAILS_ENV=staging db:migrate`.

See &quot;[Custom Rake Tasks][1]&quot;.

[1]: http://railscasts.com/episodes/66-custom-rake-tasks

It loads in your Rails environment so you can actually use your models and what not. Otherwise, it has no idea about those things.

So if you made a task that just did `puts &quot;HI!&quot;` then you don&#39;t need to add the `:environment` task to the dependencies. But if you wish to do something like `User.find(1)` well that will need it.

Including `=&gt; :environment` will tell Rake to load full the application environment, giving the relevant task access to things like classes, helpers, etc. Without the `:environment`, you won&#39;t have access to any of those extras.

Also `=&gt; :environment` itself does not make available any environment-related variables, e.g. `environment`, `@environment`, `RAILS_ENV`, etc.

I need to determine if a string contains two or more consecutive alpha chars. Two or more `[a-zA-Z]` side by side.
Example:

    &quot;ab&quot; -&gt; valid
    &quot;a1&quot; -&gt; invalid
    &quot;a b&quot; -&gt; invalid
    &quot;a&quot;-&gt; invalid
    &quot;a ab&quot; -&gt; valid
    &quot;11&quot; -&gt; invalid



RegEx to find two or more consecutive chars

In javascript I have seen `i++` used in many cases, and I understand that it adds one to the preceding value:

&lt;!-- begin snippet: js hide: false console: true babel: false --&gt;

&lt;!-- language: lang-js --&gt;

    for (var i=1; i&lt;=10; i++) {
      console.log(i);
    }

&lt;!-- end snippet --&gt;

But what happens when I do this:

    ++i;

And is it any different using the `--` operator (besides of course that it&#39;s subtraction rather than addition)?

javascript i++ vs ++i

According to &quot;[Custom Rake Tasks][1]&quot;:

    desc &quot;Pick a random user as the winner&quot;
    task :winner =&gt; :environment do
      puts &quot;Winner: #{pick(User).name}&quot;
    end

As far as I know, the `:winner =&gt; :environment` means &quot;do `environment` before `winner`&quot;. But what&#39;s `environment`? When should I use it?

I tried `rake -T`, but in the list I couldn&#39;t find `environment`.

[1]: http://railscasts.com/episodes/66-custom-rake-tasks

What&#39;s the &#39;environment&#39; task in Rake?

According to "<a href="http://railscasts.com/episodes/66-custom-rake-tasks" target="_blank" rel="noopener noreferrer">Custom Rake Tasks</a>":
<pre><code class="hljs language-ruby">desc "Pick a random user as the winner"
task :winner => :environment do
 puts "Winner: #{pick(User).name}"
end
</code></pre>
As far as I know, the <code>:winner => :environment</code> means "do <code>environment</code> before <code>winner</code>". But what's <code>environment</code>? When should I use it?
I tried <code>rake -T</code>, but in the list I couldn't find <code>environment</code>.

How to add a hash parameter in link_to. I need to generate a URL something like this..

    /p/generate/#sometext

This is how my code looks now.

    link_to &quot;Click&quot;,my_path

How to add the hash parameter to my routes method.


**Now for the answer**

When I posted the question, I didn&#39;t got through the url helpers API fully. 
http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#method-i-link_to

I did now. :) .I found the answer.

    link_to &quot;Click&quot;, my_path(:anchor =&gt; &quot;sometext&quot;)

M.cypher below almost got it. :)

Adding Hash parameter in the URL Rails Routes

My app is using Rails 3.0.4 and Devise 1.1.7.

I&#39;m looking for a way to prevent users from sharing accounts as the app is a subscription based service.  I&#39;ve been searching for over a week, and I still don&#39;t know how to implement a solution.  I&#39;m hoping someone has implemented a solution and can point me in the right direction.   

**Solution** (Thank you everyone for your answers and insight!)

In application controller.rb

    before_filter :check_concurrent_session

    def check_concurrent_session
      if is_already_logged_in?
        sign_out_and_redirect(current_user)
      end
    end

    def is_already_logged_in?
      current_user &amp;&amp; !(session[:token] == current_user.login_token)
    end

In session_controller that overrides Devise Sessions controller:

    skip_before_filter :check_concurrent_session
    
    def create
      super
      set_login_token
    end
    
    private
    def set_login_token
      token = Devise.friendly_token
      session[:token] = token
      current_user.login_token = token
      current_user.save
    end

In migration AddLoginTokenToUsers

    def self.up
      change_table &quot;users&quot; do |t|
        t.string &quot;login_token&quot;
      end
    end

    def self.down
      change_table &quot;users&quot; do |t|
        t.remove &quot;login_token&quot;
      end
    end


Devise limit one session per user at a time

I am loading a YAML file in Rails 3.0.9 like this:

    APP_CONFIG = YAML.load(File.read(File.expand_path(&#39;../app.yml&#39;, __FILE__)))

It loads the all of the contents like hierarchical hashes, no problem.  The part I don&#39;t like is the fact that the hashes can only be accessed with single or double quotes but not a symbol.  

    APP_CONFIG[&#39;mailer&#39;][&#39;username&#39;]  # works fine
    APP_CONFIG[:mailer][:username]    # doesn&#39;t

Any thoughts?

Rails load YAML to hash and reference by symbol

Since upgrading to Rails 3.1 I&#39;m seeing this warning message in my development log:

&gt; WARN  Could not determine content-length of response body. Set content-length of the response or set `Response#chunked = true`

What does this mean and how can I remove it? Is it a problem?

What does &quot;WARN Could not determine content-length of response body.&quot; mean and how to I get rid of it?

I created a new Rails project using `rails 3.1.0.rc4` on my local machine but when I try to start the server I get:
Could not find a JavaScript runtime. See [here][1] for a list of available runtimes. (`ExecJS::RuntimeUnavailable`)

Note: This is not about Heroku.


  [1]: https://github.com/sstephenson/execjs

Rails - Could not find a JavaScript runtime?

After installing devise MODEL User i got this.

    class DeviseCreateUsers &lt; ActiveRecord::Migration
      def self.up
        create_table(:users) do |t|
          t.database_authenticatable :null =&gt; false
          t.recoverable
          t.rememberable
          t.trackable
    
          # t.encryptable
          # t.confirmable
          # t.lockable :lock_strategy =&gt; :failed_attempts, :unlock_strategy =&gt; :both
          # t.token_authenticatable
    
    
          t.timestamps
        end
    
        add_index :users, :email,                :unique =&gt; true
        add_index :users, :reset_password_token, :unique =&gt; true
        # add_index :users, :confirmation_token,   :unique =&gt; true
        # add_index :users, :unlock_token,         :unique =&gt; true
        # add_index :users, :authentication_token, :unique =&gt; true
      end
    
      def self.down
        drop_table :users
      end
    end

Now if i do rake db:migrate the users table will be created.

How can i revert this migration, i.e. how can I delete the users table using rake again ?

Ruby on Rails: How can I revert a migration with rake db:migrate?

I have installed PostgreSQL on my Mac OS Lion, and am working on a rails app. I use RVM to keep everything separate from my other Rails apps.

For some reason when I try to migrate the db for the first time rake cannot find the postgres user. I get the error

     FATAL:  role &quot;postgres&quot; does not exist

I have pgAdmin so I can clearly see there is a postgres user in the DB - the admin account in fact - so I&#39;m not sure what else to do.

I read somewhere about people having issues with PostgreSQL because of which path it was installed in, but then I don&#39;t think I would have gotten that far if it couldn&#39;t find the db.

Rails and PostgreSQL: Role postgres does not exist

I have a Rails 2.2 project in which I want to override the functionality of the `rake db:test:prepare` task.  I thought this would work, but it doesn&#39;t:
    
    #lib/tasks/db.rake
    namespace :db do
      namespace :test do
        desc &quot;Overridden version of rails&#39; standard db:test:prepare task since the schema dump used in that can&#39;t handle DB enums&quot;  
        task :prepare =&gt; [:environment] do
          puts &quot;doing db:structure:dump&quot;
          Rake::Task[&#39;db:structure:dump&#39;].invoke
          puts &quot;doing db:test:clone_structure&quot;
          Rake::Task[&#39;db:test:clone_structure&#39;].invoke
        end   
      end
    end

I get the standard task&#39;s behaviour.  If I change the name of the task to `:prepare2` and then do `rake db:test:prepare2`, then it works fine.  The natural conclusion I draw from this is that my rake tasks are being defined *before* the built-in Rails ones, so mine is overridden by the standard `:prepare` task.

Can anyone see how I can fix this?  I&#39;d rather override it than have to use a new task.  Thanks, max  

Overriding rails&#39; default rake tasks

I learned Rails using just the rake command like `rake db:migrate`; however, I read that I should be using the `bundle exec rake ... ` instead of just plain `rake`. Now I&#39;m confused about which to use.

Should I be using `bundle exec rake` instead of just plain `rake` or is it just a preference thing? Any insight would be much appreciated! Thanks!

Use bundle exec rake or just rake?

&gt; **Possible Duplicate:**  
&gt; [Why is rake db:migrate:reset not listed in rake -T?](https://stackoverflow.com/questions/3951514/why-is-rake-dbmigratereset-not-listed-in-rake-t)  

&lt;!-- End of automatically inserted text --&gt;

Inside my Rails (3.1.3) application, I can run `rake db:test:prepare`. But when I run `rake -T [db]`, that task (and many others I can use) does not show up.

How do I get a complete list of tasks, or why is it incomplete in the first place?

E.g. http://mindspill.net/computing/cross-platform-notes/ruby-on-rails/how-to-list-rake-tasks/ shows that the &#39;db:test:prepare&#39; task got listed for an older Rails version when running `rails -T`.

Content Type	Original Author	Original Content on Stackoverflow
Question	Lai Yu-Hsuan	View Question on Stackoverflow
Solution 1 - Ruby on-Rails	Sameer C	View Answer on Stackoverflow
Solution 2 - Ruby on-Rails	MrDanA	View Answer on Stackoverflow
Solution 3 - Ruby on-Rails	Lars Levie	View Answer on Stackoverflow

What's the 'environment' task in Rake?

Ruby on-Rails Problem Overview

Ruby on-Rails Solutions

Solution 1 - Ruby on-Rails

Solution 2 - Ruby on-Rails

Solution 3 - Ruby on-Rails

javascript i++ vs ++i

RegEx to find two or more consecutive chars

Attributions