Ruby on Rails FAQs and Troubleshooting

Ruby on Rails is a web application framework in the Ruby programming language. It enables developers to build applications efficiently. However, you may encounter issues along the way. This article will delve into Ruby on Rails FAQs and Troubleshooting.

• FAQs
• Common Ruby on Rails Errors and Solutions
  • Ruby on Rails Error 500
  • Gems Installation
  • 404 Not Found
• Summary

FAQs

> rails -v
Rails X.X.X will be displayed.

Common Ruby on Rails Errors and Solutions

Ruby on Rails Error 500

Problem

When I attempt to execute my Ruby on Rails application I receive "500- Premature end of script."

Solution

This error generally has two potential causes:

• The file permissions are not set to allow dispatch.cgi to be executed properly. Chmod the dispatch.cgi to 0755.
• The path to Ruby is incorrect in the dispatch.cgi file. The first line of the file is called the hashbang, which sets the location of the interpreter (in this case, Ruby). Change the hashbang to the correct path to Ruby (/usr/bin/ruby). The first line of the dispatch.cgi file should look like this:
  #!/usr/bin/ruby

Gems Installation

Problem

Ruby on Rails Troubleshooting for installation

Solution

Make sure you have SSH Enabled in order to follow these directions, as it is required to install gems locally.
 

1.  Add the following lines to your $HOME/.bashrc file (these can be copied and pasted):

      export GEM_HOME=$HOME/ruby/gems
      export GEM_PATH=$GEM_HOME:/lib64/ruby/gems/1.9.3
      export GEM_CACHE=$GEM_HOME/cache
      export PATH=$PATH:$HOME/ruby/gems/bin

2. Now, edit the source file for the rack gem. This *should* be located here:

      $HOME/ruby/gems/gems/rack-1.1.6/lib/rack/handler/fastcgi.rb

   Just comment out line #7 so it looks like this:

      #alias _rack_read_without_buffer read

3. Now modify the applications environment.rb file so that the correct gem path is included. This line should go up at the top before the version of rails is specified:

     ENV['GEM_PATH'] = '/path/to/their/home/ruby/gems:/usr/lib/ruby/gems/1.9.3'

4. Kill off fastcgi processes.

404 Not Found

Problem

My Ruby on Rails installation keeps displaying a '404 Not Found' error.

Solution

Please create a .htaccess file inside the public folder with the necessary codes. See the examples below:

• Apache options:

  AddHandler fcgid-script .fcgi
  AddHandler cgi-script .cgi
  Options +SymLinksIfOwnerMatch +ExecCGI

• If you don't want Apache to rewrite requests, use the rewrite rules below:

  RewriteCond %{REQUEST_URI} ^/notrails.*
  RewriteRule .* - [L]

• For better performance, you can replace the cgi dispatcher with fastcgi:

  RewriteRule ^(.*)$ dispatch.fcgi [QSA,L]
  RewriteEngine On

• Set the RewriteBase in your file if you access Rails via the Alias directive:

  Alias /myrailsapp /path/to/myrailsapp/public
  RewriteBase /myrailsapp
  
  RewriteBase /
  RewriteRule ^$ index.html [QSA]
  RewriteRule ^([^.]+)$ $1.html [QSA]
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteRule ^(.*)$ dispatch.fcgi [QSA,L]

Summary

You may encounter some problems when using Ruby on Rails, which is a web application framework that helps its users build applications. Learn more about answers to FAQs and solutions to common issues encountered when using Ruby on Rails. Common errors include Error 500 and 404 Not Found Errors.