Ruby / Roda - Web Framework / Plugins / :multi_run

Introduction

The :multi_run plugin provides the ability to easily dispatch to other Rack applications based on the request path prefix.

First, load the plugin:

class App < Roda
  
  plugin :multi_run
  
end

Then, other Rack applications can register with the :multi_run plugin:

App.run "ra", PlainRackApp

App.run "ro", OtherRodaApp

App.run "si", SinatraApp

Inside your route block, you can call r.multi_run to dispatch to all three Rack applications based on the prefix:

App.route do |r|
  
  r.multi_run
  
end

This will dispatch routes starting with /ra to PlainRackApp, routes starting with /ro to OtherRodaApp, and routes starting with /si to SinatraApp.

The :multi_run plugin is similar to the :multi_route plugin, with the difference being the :multi_route plugin keeps all routing subtrees in the same Roda app/class, while :multi_run dispatches to other Rack apps.

If you want to isolate your routing subtrees, :multi_run is a better approach, but it does not let you set instance variables in the main Roda app and have those instance variables usable in the routing subtrees.

ClassMethods

`#.freeze`

Freeze the multi_run apps so that there can be no thread safety issues at runtime.

`#.multi_run_apps`

Hash storing rack applications to dispatch to, keyed by the prefix for the application.

`#.run(prefix, app)`

Add a rack application to dispatch to for the given prefix when r.multi_run is called.

RequestClassMethods

`#.refresh_multi_run_regexp!`

Refresh the #.multi_run_regexp, using the stored route prefixes, preferring longer routes before shorter routes.

`#.multi_run_regexp`

Refresh the #.multi_run_regexp if it hasn't been loaded yet.

RequestMethods

`#.multi_run`

If one of the stored route prefixes match the current request, dispatch the request to the stored Rack application.