rails_redirect

A rails centric rack middleware to handle redirections.

Installation

Add this line to your application's Gemfile:

gem 'rails_redirect'

And then execute:

$ bundle

Or install it yourself as:

$ gem install rails_redirect

Features

Build for Rails

Although this is a rack middleware, it's primary focus is Rails. This allows for a tight integration and a superior "works out-of-the-box" feeling. Just add it to your Gemfile, create the config and things start rolling. The middleware is automatically injected into your stack. The config allows for multiple environments, just like database.yml.

Resolves transitive redirections

In grown applications it's not uncommon, that you start with a collection /foos, which's url was renamed to /bars (probably for better SEO), just to be eventually being renamed to /muffs (for even better SEO). Legacy urls should be reachable even with your newest release, to not break peoples bookmarks.

To ease the pain of supporting multiple levels of redirection and in order to improve performance by avoiding multiple redirects, rails_redirect resolves transitive redirects and answers just with the final target. Having a config like this, a request to /foos will be directly answerd with a redirct to /muffs (no /bars involved).

rules:
- /\/foos\/?\Z/: "/bars"
- /\/bars\/?\Z/: "/muffs"

Regular expressions (with named captures)

Selectors can be written as regular expressions. Captures can be used within the transformation by using the well known \1, \2, ... notation or by assigning meaningfully names. After all, it's just Ruby regular expressions.

rules:
- /\/foos/(?<id>\d+)\Z/: "/muffs/\\k<id>" # redirects /foos/17 to /muffs/17

Supports callables

If regular expressions are not sufficient you can also use a lambda or a proc.

rules:
- /\/foos\/?\Z/: -> (env) { "/bars" }
- /\/bars\/?\Z/: |                    # multiple lines just work because of YAML
    -> (env) do
      "/muffs"
    end

`app/redirectors`

If your inline procs are getting to complex, we introduce the convention to put the logic into classes in app/redirectors.

# app/redirectors/collections_redirector.rb
class CollectionsRedirector < RailsRedirect::Redirector
  def self.call(env)
    ...
  end
end

These redirectors can than be called from within regular config defined procs like this.

rules:
  - /\/foos\/?\Z/: -> (env) { CollectionsRedirector.call(env) }

This is really just a convention. You are totaly free to go this or any other way to store complex redirection logic.

Usage

In your rails app, create config/rails_redirect.yml and set it up.

Example

# config/rails_redirect.yml
default: &default
  rules:
  - /\/de\/collections\/?\Z/: "/de/sammlungen"
  - /\/de\/collections\/(?<id>[^\/]+)\Z/: "/de/sammlungen/\\k<id>"
  - /\/de\/sammlungen\/?\Z/: "/de/specials"
  - /\/de\/sammlungen\/(?<id>[^\/]+)\Z/: "/de/specials/\\k<id>"
  - /[^\/]+\/collections\Z/: |
      -> (env) do
        "/foo/bar"
      end

development:
  <<: *default

test:
  <<: *default

production:
  <<: *default

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/msievers/rails_redirect.

License

The gem is available as open source under the terms of the MIT License.