73 lines
2.3 KiB
Ruby
73 lines
2.3 KiB
Ruby
module Zero
|
|
# makes it possible to route urls to rack applications
|
|
#
|
|
# This class can be used to build a small rack application which routes
|
|
# requests to the given application.
|
|
# In the URLs it is also possible to use placeholders which then get assigned
|
|
# as variables to the parameters.
|
|
#
|
|
# @example of a simple router
|
|
# router = Zero::Router.new(
|
|
# '/' => WelcomeController,
|
|
# '/posts' => PostController
|
|
# )
|
|
#
|
|
# @example of a router with variables
|
|
# router = Zero::Router.new(
|
|
# '/foo/:id' => FooController
|
|
# )
|
|
class Router
|
|
# match for variables in routes
|
|
VARIABLE_MATCH = %r{:(\w+)[^/]?}
|
|
# the replacement string to make it an regex
|
|
VARIABLE_REGEX = '(?<\1>[\w]+?)'
|
|
# regex part of the beginning of the line
|
|
REGEX_BEGINNING = '\A'
|
|
# regex part of the end of the line
|
|
REGEX_END = '\Z'
|
|
# environment key to store custom parameters
|
|
ENV_KEY_CUSTOM = 'zero.params.custom'
|
|
# environment key to the path info
|
|
ENV_KEY_PATH_INFO = 'PATH_INFO'
|
|
|
|
# create a new router instance
|
|
#
|
|
# @example of a simple router
|
|
# router = Zero::Router.new(
|
|
# '/' => WelcomeController,
|
|
# '/posts' => PostController
|
|
# )
|
|
#
|
|
# @param routes [Hash] a map of URLs to rack compatible applications
|
|
def initialize(routes)
|
|
@routes = {}
|
|
routes.to_a.sort_by(&:first).reverse.each do |route, target|
|
|
@routes[
|
|
Regexp.new(REGEX_BEGINNING +
|
|
route.gsub(VARIABLE_MATCH, VARIABLE_REGEX) +
|
|
REGEX_END)] = target
|
|
end
|
|
end
|
|
|
|
# call the router and call the matching application
|
|
#
|
|
# This method has to be called with a rack compatible environment, then the
|
|
# method will find a matching route and call the application.
|
|
# @param env [Hash] a rack environment
|
|
# @return [Array] a rack compatible response
|
|
def call(env)
|
|
env[ENV_KEY_CUSTOM] ||= {}
|
|
@routes.each do |route, target|
|
|
match = route.match(env[ENV_KEY_PATH_INFO])
|
|
if match
|
|
match.names.each_index do |i|
|
|
env[ENV_KEY_CUSTOM][match.names[i]] = match.captures[i]
|
|
end
|
|
return target.call(env)
|
|
end
|
|
end
|
|
[404, {'Content-Type' => 'text/html'}, ['Not found!']]
|
|
end
|
|
end
|
|
end
|