lib/rack/reducer.rb in rack-reducer-1.0.0 vs lib/rack/reducer.rb in rack-reducer-1.0.1

@@ -2,11 +2,25 @@
 require_relative 'reducer/middleware'
 
 module Rack
   # Use request params to apply filters to a dataset
   module Reducer
-    # Call Rack::Reducer as a function
+    # Filter a dataset
+    # @param params [Hash] Rack-compatible URL params
+    # @param dataset [Object] A dataset, e.g. one of your App's models
+    # @param filters [Array<Proc>] An array of lambdas with keyword arguments
+    # @example Call Rack::Reducer as a function in a Sinatra app
+    #   ArtistReducer = {
+    #     dataset: Artist,
+    #     filters: [
+    #       lambda { |name:| where(name: name) },
+    #       lambda { |genre:| where(genre: genre) },
+    #     ]
+    #   }
+    #   get '/artists' do
+    #     @artists = Rack::Reducer.call(params, ArtistReducer)
+    #   end
     def self.call(params, dataset:, filters:)
       Reduction.new(
         params: params,
         filters: filters,
         dataset: dataset
@@ -16,28 +30,27 @@
     # Mount Rack::Reducer as middleware
     def self.new(app, options = {})
       Middleware.new(app, options)
     end
 
-    # Extend Rack::Reducer to get `reduce` and `reduces` as class-methods
+    # Extend Rack::Reducer to get +reduce+ and +reduces+ as class-methods
+    # @example Make an "Artists" model reducible
+    #   class Artist < SomeORM::Model
+    #     extend Rack::Reducer
+    #     reduces self.all, filters: [
+    #       lambda { |name:| where(name: name) },
+    #       lambda { |genre:| where(genre: genre) },
+    #     ]
+    #   end
     #
-    # class Artist < SomeORM::Model
-    #   extend Rack::Reducer
-    #   reduces self.all, filters: [
-    #     lambda { |name:| where(name: name) },
-    #     lambda { |genre:| where(genre: genre) },
-    #   ]
-    # end
-    def reduce(params)
-      Reduction.new(
-        params: params,
-        filters: @rack_reducer_filters,
-        dataset: @rack_reducer_dataset
-      ).reduce
-    end
-
+    #   Artist.reduce(params)
     def reduces(dataset, filters:)
-      @rack_reducer_dataset = dataset
-      @rack_reducer_filters = filters
+      define_singleton_method :reduce do |params|
+        Reduction.new(
+          params: params,
+          filters: filters,
+          dataset: dataset,
+        ).reduce
+      end
     end
   end
 end