798 lines
32 KiB
Ruby
798 lines
32 KiB
Ruby
# encoding: UTF-8
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# --
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# Copyright (C) 2008-2010 10gen Inc.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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module Mongo
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# A named collection of documents in a database.
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class Collection
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attr_reader :db, :name, :pk_factory, :hint, :safe
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# Initialize a collection object.
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#
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# @param [DB] db a MongoDB database instance.
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# @param [String, Symbol] name the name of the collection.
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#
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# @option options [:create_pk] :pk (BSON::ObjectId) A primary key factory to use
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# other than the default BSON::ObjectId.
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#
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# @option options [Boolean, Hash] :safe (false) Set the default safe-mode options
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# for insert, update, and remove method called on this Collection instance. If no
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# value is provided, the default value set on this instance's DB will be used. This
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# default can be overridden for any invocation of insert, update, or remove.
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#
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# @raise [InvalidNSName]
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# if collection name is empty, contains '$', or starts or ends with '.'
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#
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# @raise [TypeError]
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# if collection name is not a string or symbol
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#
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# @return [Collection]
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#
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# @core collections constructor_details
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def initialize(db, name, options={})
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case name
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when Symbol, String
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else
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raise TypeError, "new_name must be a string or symbol"
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end
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name = name.to_s
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if name.empty? or name.include? ".."
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raise Mongo::InvalidNSName, "collection names cannot be empty"
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end
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if name.include? "$"
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raise Mongo::InvalidNSName, "collection names must not contain '$'" unless name =~ /((^\$cmd)|(oplog\.\$main))/
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end
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if name.match(/^\./) or name.match(/\.$/)
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raise Mongo::InvalidNSName, "collection names must not start or end with '.'"
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end
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if options.respond_to?(:create_pk) || !options.is_a?(Hash)
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warn "The method for specifying a primary key factory on a Collection has changed.\n" +
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"Please specify it as an option (e.g., :pk => PkFactory)."
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pk_factory = options
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else
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pk_factory = nil
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end
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@db, @name = db, name
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@connection = @db.connection
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@logger = @connection.logger
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@cache_time = @db.cache_time
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@cache = Hash.new(0)
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unless pk_factory
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@safe = options.has_key?(:safe) ? options[:safe] : @db.safe
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end
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@pk_factory = pk_factory || options[:pk] || BSON::ObjectId
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@hint = nil
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end
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# Return a sub-collection of this collection by name. If 'users' is a collection, then
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# 'users.comments' is a sub-collection of users.
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#
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# @param [String] name
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# the collection to return
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#
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# @raise [Mongo::InvalidNSName]
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# if passed an invalid collection name
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#
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# @return [Collection]
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# the specified sub-collection
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def [](name)
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name = "#{self.name}.#{name}"
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return Collection.new(db, name) if !db.strict? || db.collection_names.include?(name)
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raise "Collection #{name} doesn't exist. Currently in strict mode."
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end
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# Set a hint field for query optimizer. Hint may be a single field
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# name, array of field names, or a hash (preferably an [OrderedHash]).
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# If using MongoDB > 1.1, you probably don't ever need to set a hint.
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#
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# @param [String, Array, OrderedHash] hint a single field, an array of
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# fields, or a hash specifying fields
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def hint=(hint=nil)
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@hint = normalize_hint_fields(hint)
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self
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end
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# Query the database.
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#
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# The +selector+ argument is a prototype document that all results must
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# match. For example:
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#
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# collection.find({"hello" => "world"})
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#
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# only matches documents that have a key "hello" with value "world".
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# Matches can have other keys *in addition* to "hello".
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#
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# If given an optional block +find+ will yield a Cursor to that block,
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# close the cursor, and then return nil. This guarantees that partially
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# evaluated cursors will be closed. If given no block +find+ returns a
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# cursor.
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#
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# @param [Hash] selector
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# a document specifying elements which must be present for a
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# document to be included in the result set. Note that in rare cases,
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# (e.g., with $near queries), the order of keys will matter. To preserve
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# key order on a selector, use an instance of BSON::OrderedHash (only applies
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# to Ruby 1.8).
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#
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# @option opts [Array, Hash] :fields field names that should be returned in the result
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# set ("_id" will be included unless explicity excluded). By limiting results to a certain subset of fields,
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# you can cut down on network traffic and decoding time. If using a Hash, keys should be field
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# names and values should be either 1 or 0, depending on whether you want to include or exclude
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# the given field.
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# @option opts [Integer] :skip number of documents to skip from the beginning of the result set
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# @option opts [Integer] :limit maximum number of documents to return
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# @option opts [Array] :sort an array of [key, direction] pairs to sort by. Direction should
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# be specified as Mongo::ASCENDING (or :ascending / :asc) or Mongo::DESCENDING (or :descending / :desc)
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# @option opts [String, Array, OrderedHash] :hint hint for query optimizer, usually not necessary if using MongoDB > 1.1
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# @option opts [Boolean] :snapshot (false) if true, snapshot mode will be used for this query.
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# Snapshot mode assures no duplicates are returned, or objects missed, which were preset at both the start and
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# end of the query's execution. For details see http://www.mongodb.org/display/DOCS/How+to+do+Snapshotting+in+the+Mongo+Database
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# @option opts [Boolean] :batch_size (100) the number of documents to returned by the database per GETMORE operation. A value of 0
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# will let the database server decide how many results to returns. This option can be ignored for most use cases.
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# @option opts [Boolean] :timeout (true) when +true+, the returned cursor will be subject to
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# the normal cursor timeout behavior of the mongod process. When +false+, the returned cursor will never timeout. Note
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# that disabling timeout will only work when #find is invoked with a block. This is to prevent any inadvertant failure to
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# close the cursor, as the cursor is explicitly closed when block code finishes.
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#
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# @raise [ArgumentError]
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# if timeout is set to false and find is not invoked in a block
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#
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# @raise [RuntimeError]
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# if given unknown options
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#
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# @core find find-instance_method
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def find(selector={}, opts={})
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fields = opts.delete(:fields)
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fields = ["_id"] if fields && fields.empty?
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skip = opts.delete(:skip) || skip || 0
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limit = opts.delete(:limit) || 0
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sort = opts.delete(:sort)
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hint = opts.delete(:hint)
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snapshot = opts.delete(:snapshot)
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batch_size = opts.delete(:batch_size)
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timeout = (opts.delete(:timeout) == false) ? false : true
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if timeout == false && !block_given?
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raise ArgumentError, "Collection#find must be invoked with a block when timeout is disabled."
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end
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if hint
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hint = normalize_hint_fields(hint)
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else
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hint = @hint # assumed to be normalized already
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end
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raise RuntimeError, "Unknown options [#{opts.inspect}]" unless opts.empty?
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cursor = Cursor.new(self, :selector => selector, :fields => fields, :skip => skip, :limit => limit,
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:order => sort, :hint => hint, :snapshot => snapshot, :timeout => timeout, :batch_size => batch_size)
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if block_given?
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yield cursor
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cursor.close
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nil
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else
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cursor
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end
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end
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# Return a single object from the database.
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#
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# @return [OrderedHash, Nil]
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# a single document or nil if no result is found.
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#
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# @param [Hash, ObjectId, Nil] spec_or_object_id a hash specifying elements
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# which must be present for a document to be included in the result set or an
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# instance of ObjectId to be used as the value for an _id query.
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# If nil, an empty selector, {}, will be used.
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#
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# @option opts [Hash]
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# any valid options that can be send to Collection#find
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#
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# @raise [TypeError]
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# if the argument is of an improper type.
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def find_one(spec_or_object_id=nil, opts={})
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spec = case spec_or_object_id
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when nil
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{}
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when BSON::ObjectId
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{:_id => spec_or_object_id}
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when Hash
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spec_or_object_id
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else
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raise TypeError, "spec_or_object_id must be an instance of ObjectId or Hash, or nil"
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end
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find(spec, opts.merge(:limit => -1)).next_document
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end
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# Save a document to this collection.
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#
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# @param [Hash] doc
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# the document to be saved. If the document already has an '_id' key,
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# then an update (upsert) operation will be performed, and any existing
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# document with that _id is overwritten. Otherwise an insert operation is performed.
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#
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# @return [ObjectId] the _id of the saved document.
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#
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# @option opts [Boolean, Hash] :safe (+false+)
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# run the operation in safe mode, which run a getlasterror command on the
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# database to report any assertion. In addition, a hash can be provided to
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# run an fsync and/or wait for replication of the save (>= 1.5.1). See the options
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# for DB#error.
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#
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# @raise [OperationFailure] when :safe mode fails.
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#
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# @see DB#remove for options that can be passed to :safe.
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def save(doc, opts={})
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if doc.has_key?(:_id) || doc.has_key?('_id')
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id = doc[:_id] || doc['_id']
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update({:_id => id}, doc, :upsert => true, :safe => opts.fetch(:safe, @safe))
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id
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else
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insert(doc, :safe => opts.fetch(:safe, @safe))
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end
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end
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# Insert one or more documents into the collection.
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#
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# @param [Hash, Array] doc_or_docs
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# a document (as a hash) or array of documents to be inserted.
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#
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# @return [ObjectId, Array]
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# The _id of the inserted document or a list of _ids of all inserted documents.
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#
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# @option opts [Boolean, Hash] :safe (+false+)
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# run the operation in safe mode, which run a getlasterror command on the
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# database to report any assertion. In addition, a hash can be provided to
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# run an fsync and/or wait for replication of the insert (>= 1.5.1). Safe
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# options provided here will override any safe options set on this collection,
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# its database object, or the current connection. See the options on
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# for DB#get_last_error.
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#
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# @see DB#remove for options that can be passed to :safe.
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#
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# @core insert insert-instance_method
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def insert(doc_or_docs, options={})
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doc_or_docs = [doc_or_docs] unless doc_or_docs.is_a?(Array)
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doc_or_docs.collect! { |doc| @pk_factory.create_pk(doc) }
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safe = options.has_key?(:safe) ? options[:safe] : @safe
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result = insert_documents(doc_or_docs, @name, true, safe)
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result.size > 1 ? result : result.first
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end
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alias_method :<<, :insert
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# Remove all documents from this collection.
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#
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# @param [Hash] selector
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# If specified, only matching documents will be removed.
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#
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# @option opts [Boolean, Hash] :safe (+false+)
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# run the operation in safe mode, which will run a getlasterror command on the
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# database to report any assertion. In addition, a hash can be provided to
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# run an fsync and/or wait for replication of the remove (>= 1.5.1). Safe
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# options provided here will override any safe options set on this collection,
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# its database, or the current connection. See the options for DB#get_last_error for more details.
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#
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# @example remove all documents from the 'users' collection:
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# users.remove
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# users.remove({})
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#
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# @example remove only documents that have expired:
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# users.remove({:expire => {"$lte" => Time.now}})
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#
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# @return [Hash, true] Returns a Hash containing the last error object if running in safe mode.
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# Otherwise, returns true.
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#
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# @raise [Mongo::OperationFailure] an exception will be raised iff safe mode is enabled
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# and the operation fails.
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#
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# @see DB#remove for options that can be passed to :safe.
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#
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# @core remove remove-instance_method
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def remove(selector={}, opts={})
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# Initial byte is 0.
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safe = opts.has_key?(:safe) ? opts[:safe] : @safe
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message = BSON::ByteBuffer.new("\0\0\0\0")
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BSON::BSON_RUBY.serialize_cstr(message, "#{@db.name}.#{@name}")
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message.put_int(0)
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message.put_binary(BSON::BSON_CODER.serialize(selector, false, true).to_s)
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@logger.debug("MONGODB #{@db.name}['#{@name}'].remove(#{selector.inspect})") if @logger
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if safe
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@connection.send_message_with_safe_check(Mongo::Constants::OP_DELETE, message, @db.name, nil, safe)
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else
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@connection.send_message(Mongo::Constants::OP_DELETE, message)
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true
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end
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end
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# Update one or more documents in this collection.
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#
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# @param [Hash] selector
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# a hash specifying elements which must be present for a document to be updated. Note:
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# the update command currently updates only the first document matching the
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# given selector. If you want all matching documents to be updated, be sure
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# to specify :multi => true.
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# @param [Hash] document
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# a hash specifying the fields to be changed in the selected document,
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# or (in the case of an upsert) the document to be inserted
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#
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# @option [Boolean] :upsert (+false+) if true, performs an upsert (update or insert)
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# @option [Boolean] :multi (+false+) update all documents matching the selector, as opposed to
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# just the first matching document. Note: only works in MongoDB 1.1.3 or later.
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# @option opts [Boolean] :safe (+false+)
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# If true, check that the save succeeded. OperationFailure
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# will be raised on an error. Note that a safe check requires an extra
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# round-trip to the database. Safe options provided here will override any safe
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# options set on this collection, its database object, or the current collection.
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# See the options for DB#get_last_error for details.
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#
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# @return [Hash, true] Returns a Hash containing the last error object if running in safe mode.
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# Otherwise, returns true.
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#
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# @core update update-instance_method
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def update(selector, document, options={})
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# Initial byte is 0.
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safe = options.has_key?(:safe) ? options[:safe] : @safe
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message = BSON::ByteBuffer.new("\0\0\0\0")
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BSON::BSON_RUBY.serialize_cstr(message, "#{@db.name}.#{@name}")
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update_options = 0
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update_options += 1 if options[:upsert]
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update_options += 2 if options[:multi]
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message.put_int(update_options)
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message.put_binary(BSON::BSON_CODER.serialize(selector, false, true).to_s)
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message.put_binary(BSON::BSON_CODER.serialize(document, false, true).to_s)
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@logger.debug("MONGODB #{@db.name}['#{@name}'].update(#{selector.inspect}, #{document.inspect})") if @logger
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if safe
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@connection.send_message_with_safe_check(Mongo::Constants::OP_UPDATE, message, @db.name, nil, safe)
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else
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@connection.send_message(Mongo::Constants::OP_UPDATE, message, nil)
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end
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end
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# Create a new index.
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#
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# @param [String, Array] spec
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# should be either a single field name or an array of
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# [field name, direction] pairs. Directions should be specified
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# as Mongo::ASCENDING, Mongo::DESCENDING, or Mongo::GEO2D.
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#
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# Note that geospatial indexing only works with versions of MongoDB >= 1.3.3+. Keep in mind, too,
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# that in order to geo-index a given field, that field must reference either an array or a sub-object
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# where the first two values represent x- and y-coordinates. Examples can be seen below.
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#
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# Also note that it is permissible to create compound indexes that include a geospatial index as
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# long as the geospatial index comes first.
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#
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# If your code calls create_index frequently, you can use Collection#ensure_index to cache these calls
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# and thereby prevent excessive round trips to the database.
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#
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# @option opts [Boolean] :unique (false) if true, this index will enforce a uniqueness constraint.
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# @option opts [Boolean] :background (false) indicate that the index should be built in the background. This
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# feature is only available in MongoDB >= 1.3.2.
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# @option opts [Boolean] :drop_dups (nil) If creating a unique index on a collection with pre-existing records,
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# this option will keep the first document the database indexes and drop all subsequent with duplicate values.
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# @option opts [Integer] :min (nil) specify the minimum longitude and latitude for a geo index.
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# @option opts [Integer] :max (nil) specify the maximum longitude and latitude for a geo index.
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#
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# @example Creating a compound index:
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# @posts.create_index([['subject', Mongo::ASCENDING], ['created_at', Mongo::DESCENDING]])
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#
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# @example Creating a geospatial index:
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# @restaurants.create_index([['location', Mongo::GEO2D]])
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#
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# # Note that this will work only if 'location' represents x,y coordinates:
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# {'location': [0, 50]}
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# {'location': {'x' => 0, 'y' => 50}}
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# {'location': {'latitude' => 0, 'longitude' => 50}}
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#
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# @example A geospatial index with alternate longitude and latitude:
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# @restaurants.create_index([['location', Mongo::GEO2D]], :min => 500, :max => 500)
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#
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# @return [String] the name of the index created.
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#
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# @core indexes create_index-instance_method
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def create_index(spec, opts={})
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opts[:dropDups] = opts.delete(:drop_dups) if opts[:drop_dups]
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field_spec = parse_index_spec(spec)
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name = opts.delete(:name) || generate_index_name(field_spec)
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generate_indexes(field_spec, name, opts)
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name
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end
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# Calls create_index and sets a flag to not do so again for another X minutes.
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# this time can be specified as an option when initializing a Mongo::DB object as options[:cache_time]
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# Any changes to an index will be propogated through regardless of cache time (e.g., a change of index direction)
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#
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# The parameters and options for this methods are the same as those for Collection#create_index.
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#
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# @example Call sequence:
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# Time t: @posts.ensure_index([['subject', Mongo::ASCENDING]) -- calls create_index and
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# sets the 5 minute cache
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# Time t+2min : @posts.ensure_index([['subject', Mongo::ASCENDING]) -- doesn't do anything
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# Time t+3min : @posts.ensure_index([['something_else', Mongo::ASCENDING]) -- calls create_index
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# and sets 5 minute cache
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# Time t+10min : @posts.ensure_index([['subject', Mongo::ASCENDING]) -- calls create_index and
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# resets the 5 minute counter
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#
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# @return [String] the name of the index.
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def ensure_index(spec, opts={})
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valid = BSON::OrderedHash.new
|
|
now = Time.now.utc.to_i
|
|
field_spec = parse_index_spec(spec)
|
|
|
|
field_spec.each do |key, value|
|
|
cache_key = generate_index_name({key => value})
|
|
timeout = @cache[cache_key] || 0
|
|
valid[key] = value if timeout <= now
|
|
end
|
|
|
|
name = opts.delete(:name) || generate_index_name(valid)
|
|
generate_indexes(valid, name, opts) if valid.any?
|
|
|
|
# Reset the cache here in case there are any errors inserting. Best to be safe.
|
|
@cache[name] = now + @cache_time
|
|
name
|
|
end
|
|
|
|
# Drop a specified index.
|
|
#
|
|
# @param [String] name
|
|
#
|
|
# @core indexes
|
|
def drop_index(name)
|
|
@cache[name] = nil
|
|
@db.drop_index(@name, name)
|
|
end
|
|
|
|
# Drop all indexes.
|
|
#
|
|
# @core indexes
|
|
def drop_indexes
|
|
@cache = {}
|
|
|
|
# Note: calling drop_indexes with no args will drop them all.
|
|
@db.drop_index(@name, '*')
|
|
end
|
|
|
|
# Drop the entire collection. USE WITH CAUTION.
|
|
def drop
|
|
@db.drop_collection(@name)
|
|
end
|
|
|
|
# Atomically update and return a document using MongoDB's findAndModify command. (MongoDB > 1.3.0)
|
|
#
|
|
# @option opts [Hash] :query ({}) a query selector document for matching the desired document.
|
|
# @option opts [Hash] :update (nil) the update operation to perform on the matched document.
|
|
# @option opts [Array, String, OrderedHash] :sort ({}) specify a sort option for the query using any
|
|
# of the sort options available for Cursor#sort. Sort order is important if the query will be matching
|
|
# multiple documents since only the first matching document will be updated and returned.
|
|
# @option opts [Boolean] :remove (false) If true, removes the the returned document from the collection.
|
|
# @option opts [Boolean] :new (false) If true, returns the updated document; otherwise, returns the document
|
|
# prior to update.
|
|
#
|
|
# @return [Hash] the matched document.
|
|
#
|
|
# @core findandmodify find_and_modify-instance_method
|
|
def find_and_modify(opts={})
|
|
cmd = BSON::OrderedHash.new
|
|
cmd[:findandmodify] = @name
|
|
cmd.merge!(opts)
|
|
cmd[:sort] = Mongo::Support.format_order_clause(opts[:sort]) if opts[:sort]
|
|
|
|
@db.command(cmd)['value']
|
|
end
|
|
|
|
# Perform a map/reduce operation on the current collection.
|
|
#
|
|
# @param [String, BSON::Code] map a map function, written in JavaScript.
|
|
# @param [String, BSON::Code] reduce a reduce function, written in JavaScript.
|
|
#
|
|
# @option opts [Hash] :query ({}) a query selector document, like what's passed to #find, to limit
|
|
# the operation to a subset of the collection.
|
|
# @option opts [Array] :sort ([]) an array of [key, direction] pairs to sort by. Direction should
|
|
# be specified as Mongo::ASCENDING (or :ascending / :asc) or Mongo::DESCENDING (or :descending / :desc)
|
|
# @option opts [Integer] :limit (nil) if passing a query, number of objects to return from the collection.
|
|
# @option opts [String, BSON::Code] :finalize (nil) a javascript function to apply to the result set after the
|
|
# map/reduce operation has finished.
|
|
# @option opts [String] :out (nil) the name of the output collection. If specified, the collection will not be treated as temporary.
|
|
# @option opts [Boolean] :keeptemp (false) if true, the generated collection will be persisted. default is false.
|
|
# @option opts [Boolean ] :verbose (false) if true, provides statistics on job execution time.
|
|
# @option opts [Boolean] :raw (false) if true, return the raw result object from the map_reduce command, and not
|
|
# the instantiated collection that's returned by default.
|
|
#
|
|
# @return [Collection] a collection containing the results of the operation.
|
|
#
|
|
# @see http://www.mongodb.org/display/DOCS/MapReduce Offical MongoDB map/reduce documentation.
|
|
#
|
|
# @core mapreduce map_reduce-instance_method
|
|
def map_reduce(map, reduce, opts={})
|
|
map = BSON::Code.new(map) unless map.is_a?(BSON::Code)
|
|
reduce = BSON::Code.new(reduce) unless reduce.is_a?(BSON::Code)
|
|
raw = opts.delete(:raw)
|
|
|
|
hash = BSON::OrderedHash.new
|
|
hash['mapreduce'] = self.name
|
|
hash['map'] = map
|
|
hash['reduce'] = reduce
|
|
hash.merge! opts
|
|
|
|
result = @db.command(hash)
|
|
unless Mongo::Support.ok?(result)
|
|
raise Mongo::OperationFailure, "map-reduce failed: #{result['errmsg']}"
|
|
end
|
|
|
|
if raw
|
|
result
|
|
else
|
|
@db[result["result"]]
|
|
end
|
|
end
|
|
alias :mapreduce :map_reduce
|
|
|
|
# Perform a group aggregation.
|
|
#
|
|
# @param [Array, String, BSON::Code, Nil] :key either 1) an array of fields to group by,
|
|
# 2) a javascript function to generate the key object, or 3) nil.
|
|
# @param [Hash] condition an optional document specifying a query to limit the documents over which group is run.
|
|
# @param [Hash] initial initial value of the aggregation counter object
|
|
# @param [String, BSON::Code] reduce aggregation function, in JavaScript
|
|
# @param [String, BSON::Code] finalize :: optional. a JavaScript function that receives and modifies
|
|
# each of the resultant grouped objects. Available only when group is run
|
|
# with command set to true.
|
|
#
|
|
# @return [Array] the grouped items.
|
|
def group(key, condition, initial, reduce, finalize=nil)
|
|
reduce = BSON::Code.new(reduce) unless reduce.is_a?(BSON::Code)
|
|
|
|
group_command = {
|
|
"group" => {
|
|
"ns" => @name,
|
|
"$reduce" => reduce,
|
|
"cond" => condition,
|
|
"initial" => initial
|
|
}
|
|
}
|
|
|
|
unless key.nil?
|
|
if key.is_a? Array
|
|
key_type = "key"
|
|
key_value = {}
|
|
key.each { |k| key_value[k] = 1 }
|
|
else
|
|
key_type = "$keyf"
|
|
key_value = key.is_a?(BSON::Code) ? key : BSON::Code.new(key)
|
|
end
|
|
|
|
group_command["group"][key_type] = key_value
|
|
end
|
|
|
|
finalize = BSON::Code.new(finalize) if finalize.is_a?(String)
|
|
if finalize.is_a?(BSON::Code)
|
|
group_command['group']['finalize'] = finalize
|
|
end
|
|
|
|
result = @db.command(group_command)
|
|
|
|
if Mongo::Support.ok?(result)
|
|
result["retval"]
|
|
else
|
|
raise OperationFailure, "group command failed: #{result['errmsg']}"
|
|
end
|
|
end
|
|
|
|
# Return a list of distinct values for +key+ across all
|
|
# documents in the collection. The key may use dot notation
|
|
# to reach into an embedded object.
|
|
#
|
|
# @param [String, Symbol, OrderedHash] key or hash to group by.
|
|
# @param [Hash] query a selector for limiting the result set over which to group.
|
|
#
|
|
# @example Saving zip codes and ages and returning distinct results.
|
|
# @collection.save({:zip => 10010, :name => {:age => 27}})
|
|
# @collection.save({:zip => 94108, :name => {:age => 24}})
|
|
# @collection.save({:zip => 10010, :name => {:age => 27}})
|
|
# @collection.save({:zip => 99701, :name => {:age => 24}})
|
|
# @collection.save({:zip => 94108, :name => {:age => 27}})
|
|
#
|
|
# @collection.distinct(:zip)
|
|
# [10010, 94108, 99701]
|
|
# @collection.distinct("name.age")
|
|
# [27, 24]
|
|
#
|
|
# # You may also pass a document selector as the second parameter
|
|
# # to limit the documents over which distinct is run:
|
|
# @collection.distinct("name.age", {"name.age" => {"$gt" => 24}})
|
|
# [27]
|
|
#
|
|
# @return [Array] an array of distinct values.
|
|
def distinct(key, query=nil)
|
|
raise MongoArgumentError unless [String, Symbol].include?(key.class)
|
|
command = BSON::OrderedHash.new
|
|
command[:distinct] = @name
|
|
command[:key] = key.to_s
|
|
command[:query] = query
|
|
|
|
@db.command(command)["values"]
|
|
end
|
|
|
|
# Rename this collection.
|
|
#
|
|
# Note: If operating in auth mode, the client must be authorized as an admin to
|
|
# perform this operation.
|
|
#
|
|
# @param [String] new_name the new name for this collection
|
|
#
|
|
# @return [String] the name of the new collection.
|
|
#
|
|
# @raise [Mongo::InvalidNSName] if +new_name+ is an invalid collection name.
|
|
def rename(new_name)
|
|
case new_name
|
|
when Symbol, String
|
|
else
|
|
raise TypeError, "new_name must be a string or symbol"
|
|
end
|
|
|
|
new_name = new_name.to_s
|
|
|
|
if new_name.empty? or new_name.include? ".."
|
|
raise Mongo::InvalidNSName, "collection names cannot be empty"
|
|
end
|
|
if new_name.include? "$"
|
|
raise Mongo::InvalidNSName, "collection names must not contain '$'"
|
|
end
|
|
if new_name.match(/^\./) or new_name.match(/\.$/)
|
|
raise Mongo::InvalidNSName, "collection names must not start or end with '.'"
|
|
end
|
|
|
|
@db.rename_collection(@name, new_name)
|
|
@name = new_name
|
|
end
|
|
|
|
# Get information on the indexes for this collection.
|
|
#
|
|
# @return [Hash] a hash where the keys are index names.
|
|
#
|
|
# @core indexes
|
|
def index_information
|
|
@db.index_information(@name)
|
|
end
|
|
|
|
# Return a hash containing options that apply to this collection.
|
|
# For all possible keys and values, see DB#create_collection.
|
|
#
|
|
# @return [Hash] options that apply to this collection.
|
|
def options
|
|
@db.collections_info(@name).next_document['options']
|
|
end
|
|
|
|
# Return stats on the collection. Uses MongoDB's collstats command.
|
|
#
|
|
# @return [Hash]
|
|
def stats
|
|
@db.command({:collstats => @name})
|
|
end
|
|
|
|
# Get the number of documents in this collection.
|
|
#
|
|
# @return [Integer]
|
|
def count
|
|
find().count()
|
|
end
|
|
|
|
alias :size :count
|
|
|
|
protected
|
|
|
|
def normalize_hint_fields(hint)
|
|
case hint
|
|
when String
|
|
{hint => 1}
|
|
when Hash
|
|
hint
|
|
when nil
|
|
nil
|
|
else
|
|
h = BSON::OrderedHash.new
|
|
hint.to_a.each { |k| h[k] = 1 }
|
|
h
|
|
end
|
|
end
|
|
|
|
private
|
|
|
|
def parse_index_spec(spec)
|
|
field_spec = BSON::OrderedHash.new
|
|
if spec.is_a?(String) || spec.is_a?(Symbol)
|
|
field_spec[spec.to_s] = 1
|
|
elsif spec.is_a?(Array) && spec.all? {|field| field.is_a?(Array) }
|
|
spec.each do |f|
|
|
if [Mongo::ASCENDING, Mongo::DESCENDING, Mongo::GEO2D].include?(f[1])
|
|
field_spec[f[0].to_s] = f[1]
|
|
else
|
|
raise MongoArgumentError, "Invalid index field #{f[1].inspect}; " +
|
|
"should be one of Mongo::ASCENDING (1), Mongo::DESCENDING (-1) or Mongo::GEO2D ('2d')."
|
|
end
|
|
end
|
|
else
|
|
raise MongoArgumentError, "Invalid index specification #{spec.inspect}; " +
|
|
"should be either a string, symbol, or an array of arrays."
|
|
end
|
|
field_spec
|
|
end
|
|
|
|
def generate_indexes(field_spec, name, opts)
|
|
selector = {
|
|
:name => name,
|
|
:ns => "#{@db.name}.#{@name}",
|
|
:key => field_spec
|
|
}
|
|
selector.merge!(opts)
|
|
|
|
begin
|
|
insert_documents([selector], Mongo::DB::SYSTEM_INDEX_COLLECTION, false, true)
|
|
|
|
rescue Mongo::OperationFailure => e
|
|
if selector[:dropDups] && e.message =~ /^11000/
|
|
# NOP. If the user is intentionally dropping dups, we can ignore duplicate key errors.
|
|
else
|
|
raise Mongo::OperationFailure, "Failed to create index #{selector.inspect} with the following error: " +
|
|
"#{e.message}"
|
|
end
|
|
end
|
|
|
|
nil
|
|
end
|
|
|
|
# Sends a Mongo::Constants::OP_INSERT message to the database.
|
|
# Takes an array of +documents+, an optional +collection_name+, and a
|
|
# +check_keys+ setting.
|
|
def insert_documents(documents, collection_name=@name, check_keys=true, safe=false)
|
|
# Initial byte is 0.
|
|
message = BSON::ByteBuffer.new("\0\0\0\0")
|
|
BSON::BSON_RUBY.serialize_cstr(message, "#{@db.name}.#{collection_name}")
|
|
documents.each do |doc|
|
|
message.put_binary(BSON::BSON_CODER.serialize(doc, check_keys, true).to_s)
|
|
end
|
|
raise InvalidOperation, "Exceded maximum insert size of 16,000,000 bytes" if message.size > 16_000_000
|
|
|
|
@logger.debug("MONGODB #{@db.name}['#{collection_name}'].insert(#{documents.inspect})") if @logger
|
|
if safe
|
|
@connection.send_message_with_safe_check(Mongo::Constants::OP_INSERT, message, @db.name, nil, safe)
|
|
else
|
|
@connection.send_message(Mongo::Constants::OP_INSERT, message, nil)
|
|
end
|
|
documents.collect { |o| o[:_id] || o['_id'] }
|
|
end
|
|
|
|
def generate_index_name(spec)
|
|
indexes = []
|
|
spec.each_pair do |field, direction|
|
|
indexes.push("#{field}_#{direction}")
|
|
end
|
|
indexes.join("_")
|
|
end
|
|
end
|
|
|
|
end
|