lib/roda/plugins/symbol_matchers.rb
# frozen-string-literal: true # class Roda module RodaPlugins # The symbol_matchers plugin allows you do define custom regexps to use # for specific symbols. For example, if you have a route such as: # # r.on :username do # # ... # end # # By default this will match all nonempty segments. However, if your usernames # must be 6-20 characters, and can only contain +a-z+ and +0-9+, you can do: # # plugin :symbol_matchers # symbol_matcher :username, /([a-z0-9]{6,20})/ # # Then the route will only if the path is +/foobar123+, but not if it is # +/foo+, +/FooBar123+, or +/foobar_123+. # # By default, this plugin sets up the following symbol matchers: # # :d :: <tt>/(\d+)/</tt>, a decimal segment # :rest :: <tt>/(.*)/</tt>, all remaining characters, if any # :w :: <tt>/(\w+)/</tt>, a alphanumeric segment # # If the placeholder_string_matchers plugin is loaded, this feature also applies to # placeholders in strings, so the following: # # r.on "users/:username" do # # ... # end # # Would match +/users/foobar123+, but not +/users/foo+, +/users/FooBar123+, # or +/users/foobar_123+. # # If using this plugin with the params_capturing plugin, this plugin should # be loaded first. module SymbolMatchers def self.load_dependencies(app) app.plugin :_symbol_regexp_matchers end def self.configure(app) app.symbol_matcher(:d, /(\d+)/) app.symbol_matcher(:w, /(\w+)/) app.symbol_matcher(:rest, /(.*)/) end module ClassMethods # Set the regexp to use for the given symbol, instead of the default. def symbol_matcher(s, re) meth = :"match_symbol_#{s}" self::RodaRequest.send(:define_method, meth){re} self::RodaRequest.send(:private, meth) end end module RequestMethods private # Use regular expressions to the symbol-specific regular expression # if the symbol is registered. Otherwise, call super for the default # behavior. def _match_symbol(s) meth = :"match_symbol_#{s}" if respond_to?(meth, true) # Allow calling private match methods re = send(meth) consume(self.class.cached_matcher(re){re}) else super end end # Return the symbol-specific regular expression if one is registered. # Otherwise, call super for the default behavior. def _match_symbol_regexp(s) meth = :"match_symbol_#{s}" if respond_to?(meth, true) # Allow calling private match methods send(meth) else super end end end end register_plugin(:symbol_matchers, SymbolMatchers) end end