Merge pull request #677 from estolfo/RUBY-1006-query-modifiers

RUBY-1006 Refactor View and Readable to allow for arbtirary query modifiers

Author: estolfo

lib/mongo/collection/view.rb

@@ -127,8 +127,7 @@ def hash
       def initialize(collection, selector = {}, options = {})
         validate_doc!(selector)
         @collection = collection
-        @selector = selector.dup
-        @options = options.dup
+        setup(selector, options)
       end
 
       # Get a human-readable string representation of +View+.

lib/mongo/collection/view/immutable.rb

@@ -22,14 +22,14 @@ module Immutable
 
         private
 
-        # @api private
-        #
-        # @note In the including class, the method #immutable needs to be
-        #   implemented in order to define how a new class of that type needs to
-        #   be instantiated.
         def configure(field, value)
           return options[field] if value.nil?
-          new(options.merge(field => value))
+          new(options.merge(field => value, :modifiers => @modifiers))
+        end
+
+        def configure_modifier(field, value)
+          return @modifiers[Readable::SPECIAL_FIELDS[field]] if value.nil?
+          new(options.merge(:modifiers => @modifiers.merge(Readable::SPECIAL_FIELDS[field] => value)))
         end
 
         def configure_flag(flag)

lib/mongo/collection/view/map_reduce.rb

@@ -159,12 +159,16 @@ def map_reduce_spec
               :mapreduce => collection.name,
               :map => map,
               :reduce => reduce,
-              :query => view.selector[:$query] || view.selector,
+              :query => view.modifiers[:$query] || view.selector,
               :out => { inline: 1 }
-            }.merge(options).merge(view.options)
+            }.merge(options).merge(view_options)
           }
         end
 
+        def view_options
+          view.sort ? view.options.merge(:sort => view.sort) : view.options
+        end
+
         def new(options)
           MapReduce.new(view, map, reduce, options)
         end

lib/mongo/collection/view/readable.rb

@@ -21,30 +21,23 @@ class View
       # @since 2.0.0
       module Readable
 
-        # Special fields and their getters for the query selector.
+        # Special fields and their option names for the query selector.
         #
         # @since 2.0.0
         SPECIAL_FIELDS = {
-          :$query => :selector,
-          :$readPreference => :read_pref_formatted,
-          :$orderby => :sort,
-          :$hint => :hint,
-          :$comment => :comment,
-          :$snapshot => :snapshot,
-          :$maxScan => :max_scan,
-          :$max => :max_value,
-          :$min => :min_value,
-          :$maxTimeMS => :max_time_ms,
-          :$returnKey => :return_key,
-          :$showDiskLoc => :show_disk_loc,
-          :$explain => :explained?
+            :sort => :$orderby,
+            :hint => :$hint,
+            :comment => :$comment,
+            :snapshot => :$snapshot,
+            :max_scan => :$maxScan,
+            :max_value => :$max,
+            :min_value => :$min,
+            :max_time_ms => :$maxTimeMS,
+            :return_key => :$returnKey,
+            :show_disk_loc => :$showDiskLoc,
+            :explain => :$explain
         }.freeze
 
-        # Get just the names of the special fields.
-        #
-        # @since 2.1.0
-        SPECIAL_FIELD_OPTION_NAMES = SPECIAL_FIELDS.values.freeze
-
         # Options to cursor flags mapping.
         #
         # @since 2.1.0
@@ -99,7 +92,7 @@ def allow_partial_results
         #
         # @since 2.0.0
         def batch_size(batch_size = nil)
-          configure(:batch_size, batch_size)
+          configure(__method__, batch_size)
         end
 
         # Associate a comment with the query.
@@ -117,7 +110,7 @@ def batch_size(batch_size = nil)
         #
         # @since 2.0.0
         def comment(comment = nil)
-          configure(:comment, comment)
+          configure_modifier(__method__, comment)
         end
 
         # Get a count of matching documents in the collection.
@@ -181,7 +174,7 @@ def distinct(field_name, options={})
         #
         # @since 2.0.0
         def hint(hint = nil)
-          configure(:hint, hint)
+          configure_modifier(__method__, hint)
         end
 
         # The max number of docs to return from the query.
@@ -195,7 +188,7 @@ def hint(hint = nil)
         #
         # @since 2.0.0
         def limit(limit = nil)
-          configure(:limit, limit)
+          configure(__method__, limit)
         end
 
         # Execute a map/reduce operation on the collection view.
@@ -225,7 +218,7 @@ def map_reduce(map, reduce, options = {})
         #
         # @since 2.0.0
         def max_scan(value = nil)
-          configure(:max_scan, value)
+          configure_modifier(__method__, value)
         end
 
         # Set the maximum value to search.
@@ -239,7 +232,7 @@ def max_scan(value = nil)
         #
         # @since 2.1.0
         def max_value(value = nil)
-          configure(:max_value, value)
+          configure_modifier(__method__, value)
         end
 
         # Set the minimum value to search.
@@ -253,7 +246,7 @@ def max_value(value = nil)
         #
         # @since 2.1.0
         def min_value(value = nil)
-          configure(:min_value, value)
+          configure_modifier(__method__, value)
         end
 
         # The server normally times out idle cursors after an inactivity period
@@ -266,7 +259,7 @@ def min_value(value = nil)
         #
         # @since 2.0.0
         def no_cursor_timeout
-          configure_flag(:no_cursor_timeout)
+          configure_flag(__method__)
         end
 
         # The fields to include or exclude from each doc in the result set.
@@ -285,7 +278,7 @@ def no_cursor_timeout
         # @since 2.0.0
         def projection(document = nil)
           validate_doc!(document) if document
-          configure(:projection, document)
+          configure(__method__, document)
         end
 
         # The read preference to use for the query.
@@ -301,7 +294,7 @@ def projection(document = nil)
         # @since 2.0.0
         def read(value = nil)
           return default_read if value.nil?
-          configure(:read, value.is_a?(Hash) ? ServerSelector.get(value) : value)
+          configure(__method__, value.is_a?(Hash) ? ServerSelector.get(value) : value)
         end
 
         # Set whether to return only the indexed field or fields.
@@ -315,7 +308,7 @@ def read(value = nil)
         #
         # @since 2.1.0
         def return_key(value = nil)
-          configure(:return_key, value)
+          configure_modifier(__method__, value)
         end
 
         # Set whether the disk location should be shown for each document.
@@ -330,7 +323,7 @@ def return_key(value = nil)
         #
         # @since 2.0.0
         def show_disk_loc(value = nil)
-          configure(:show_disk_loc, value)
+          configure_modifier(__method__, value)
         end
 
         # The number of docs to skip before returning results.
@@ -345,7 +338,7 @@ def show_disk_loc(value = nil)
         #
         # @since 2.0.0
         def skip(number = nil)
-          configure(:skip, number)
+          configure(__method__, number)
         end
 
         # Set the snapshot value for the view.
@@ -360,7 +353,7 @@ def skip(number = nil)
         #
         # @since 2.0.0
         def snapshot(value = nil)
-          configure(:snapshot, value)
+          configure_modifier(__method__, value)
         end
 
         # The key and direction pairs by which the result set will be sorted.
@@ -375,7 +368,7 @@ def snapshot(value = nil)
         #
         # @since 2.0.0
         def sort(spec = nil)
-          configure(:sort, spec)
+          configure_modifier(__method__, spec)
         end
 
         # “meta” operators that let you modify the output or behavior of a query.
@@ -389,7 +382,8 @@ def sort(spec = nil)
         #
         # @since 2.1.0
         def modifiers(doc = nil)
-          configure(:modifiers, doc)
+          return @modifiers if doc.nil?
+          new(options.merge(__method__ => doc))
         end
 
         # A cumulative time limit in milliseconds for processing operations on a cursor.
@@ -403,7 +397,7 @@ def modifiers(doc = nil)
         #
         # @since 2.1.0
         def max_time_ms(max = nil)
-          configure(:max_time_ms, max)
+          configure_modifier(__method__, max)
         end
 
         private
@@ -421,10 +415,6 @@ def flags
           end
         end
 
-        def has_special_fields?
-          contains_modifiers? || explained? || cluster.sharded?
-        end
-
         def parallel_scan(cursor_count)
           server = read.select_server(cluster)
           Operation::ParallelScan.new(
@@ -441,6 +431,27 @@ def parallel_scan(cursor_count)
           end
         end
 
+        def setup(sel, opts)
+          setup_options(opts)
+          setup_selector(sel)
+        end
+
+        def setup_options(opts)
+          @options = opts ? opts.dup : {}
+          @modifiers = @options[:modifiers] ? @options.delete(:modifiers).dup : BSON::Document.new
+          @options.keys.each { |k| @modifiers.merge!(SPECIAL_FIELDS[k] => @options.delete(k)) if SPECIAL_FIELDS[k] }
+          @options.freeze
+        end
+
+        def setup_selector(sel)
+          @selector = sel ? sel.dup : {}
+          if @selector[:$query] || @selector['$query']
+            @selector.keys.each { |k| @modifiers.merge!(k => @selector.delete(k)) if k[0] == '$' }
+          end
+          @modifiers.freeze
+          @selector.freeze
+        end
+
         def query_options
           {
             :project => projection,
@@ -451,8 +462,12 @@ def query_options
           }
         end
 
+        def requires_special_selector?
+          !modifiers.empty? || cluster.sharded?
+        end
+
         def query_spec
-          sel = has_special_fields? ? special_selector : selector
+          sel = requires_special_selector? ? special_selector : selector
           { :selector  => sel,
             :read      => read,
             :options   => query_options,
@@ -461,26 +476,18 @@ def query_spec
         end
 
         def read_pref_formatted
-          read.to_mongos
+          @read_formatted ||= read.to_mongos
         end
 
         def special_selector
-          SPECIAL_FIELDS.reduce({}) do |hash, (key, method)|
-            value = send(method) || (options[:modifiers] && options[:modifiers][key])
-            hash[key] = value unless value.nil?
-            hash
-          end
+          sel = BSON::Document.new(:$query => selector).merge!(modifiers)
+          sel[:$readPreference] = read_pref_formatted unless read_pref_formatted.nil?
+          sel
         end
 
         def validate_doc!(doc)
           raise Error::InvalidDocument.new unless doc.respond_to?(:keys)
         end
-
-        def contains_modifiers?
-          modifiers || options.keys.any? do |key|
-            SPECIAL_FIELD_OPTION_NAMES.include?(key)
-          end
-        end
       end
     end
   end

lib/mongo/grid/fs_bucket.rb

@@ -261,13 +261,19 @@ def download_to_stream(id, io)
       #
       # @since 2.1.0
       def open_download_stream_by_name(filename, opts = {}, &block)
-        view = files_collection.find(:filename => filename).projection(_id: 1)
         revision = opts.fetch(:revision, -1)
         if revision < 0
-          file_doc = view.sort('uploadDate' => Mongo::Index::DESCENDING).skip(revision.abs - 1).limit(-1).first
+          skip = revision.abs - 1
+          sort = { 'uploadDate' => Mongo::Index::DESCENDING }
         else
-          file_doc = view.sort('uploadDate' => Mongo::Index::ASCENDING).skip(revision).limit(-1).first
+          skip = revision
+          sort = { 'uploadDate' => Mongo::Index::ASCENDING }
         end
+        file_doc = files_collection.find({ filename: filename} ,
+                                           projection: { _id: 1 },
+                                           sort: sort,
+                                           skip: skip,
+                                           limit: -1).first
         unless file_doc
           raise Error::FileNotFound.new(filename, :filename) unless opts[:revision]
           raise Error::InvalidFileRevision.new(filename, opts[:revision])

lib/mongo/grid/stream/read.rb

@@ -49,8 +49,8 @@ class Read
           # @since 2.1.0
           def initialize(fs, options)
             @fs = fs
-            @options = options
-            @file_id = options[:file_id]
+            @options = options.dup
+            @file_id = @options.delete(:file_id)
             @open = true
           end
 

lib/mongo/protocol/query.rb

@@ -258,7 +258,7 @@ def op_command
         def find_command
           document = BSON::Document.new
           document[:find] = collection
-          document[:filter] = filter.key?(:$query) ? filter[:$query] : filter
+          document[:filter] = filter[:$query] ? filter[:$query] : filter
           OPTION_MAPPINGS.each do |legacy, option|
             document[option] = options[legacy] unless options[legacy].nil?
           end