509 lines
18 KiB
Ruby
509 lines
18 KiB
Ruby
# --
|
|
# Copyright (C) 2008-2009 10gen Inc.
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
# ++
|
|
|
|
module Mongo
|
|
|
|
# A named collection of records in a database.
|
|
class Collection
|
|
|
|
attr_reader :db, :name, :pk_factory, :hint
|
|
|
|
def initialize(db, name, pk_factory=nil)
|
|
case name
|
|
when Symbol, String
|
|
else
|
|
raise TypeError, "new_name must be a string or symbol"
|
|
end
|
|
|
|
name = name.to_s
|
|
|
|
if name.empty? or name.include? ".."
|
|
raise InvalidName, "collection names cannot be empty"
|
|
end
|
|
if name.include? "$" and not name.match(/^\$cmd/)
|
|
raise InvalidName, "collection names must not contain '$'"
|
|
end
|
|
if name.match(/^\./) or name.match(/\.$/)
|
|
raise InvalidName, "collection names must not start or end with '.'"
|
|
end
|
|
|
|
@db, @name = db, name
|
|
@pk_factory = pk_factory || ObjectID
|
|
@hint = nil
|
|
end
|
|
|
|
# Get a sub-collection of this collection by name.
|
|
#
|
|
# Raises InvalidName if an invalid collection name is used.
|
|
#
|
|
# :name :: the name of the collection to get
|
|
def [](name)
|
|
name = "#{self.name}.#{name}"
|
|
return Collection.new(db, name) if !db.strict? || db.collection_names.include?(name)
|
|
raise "Collection #{name} doesn't exist. Currently in strict mode."
|
|
end
|
|
|
|
# Set hint fields to use and return +self+. hint may be a single field
|
|
# name, array of field names, or a hash (preferably an OrderedHash).
|
|
# May be +nil+.
|
|
def hint=(hint)
|
|
@hint = normalize_hint_fields(hint)
|
|
self
|
|
end
|
|
|
|
# Query the database.
|
|
#
|
|
# The +selector+ argument is a prototype document that all results must
|
|
# match. For example:
|
|
#
|
|
# collection.find({"hello" => "world"})
|
|
#
|
|
# only matches documents that have a key "hello" with value "world".
|
|
# Matches can have other keys *in addition* to "hello".
|
|
#
|
|
# If given an optional block +find+ will yield a Cursor to that block,
|
|
# close the cursor, and then return nil. This guarantees that partially
|
|
# evaluated cursors will be closed. If given no block +find+ returns a
|
|
# cursor.
|
|
#
|
|
# :selector :: A document (hash) specifying elements which must be
|
|
# present for a document to be included in the result set.
|
|
#
|
|
# Options:
|
|
# :fields :: Array of field names that should be returned in the result
|
|
# set ("_id" will always be included). By limiting results
|
|
# to a certain subset of fields you can cut down on network
|
|
# traffic and decoding time.
|
|
# :skip :: Number of documents to omit (from the start of the result set)
|
|
# when returning the results
|
|
# :limit :: Maximum number of records to return
|
|
# :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)
|
|
# :hint :: See #hint. This option overrides the collection-wide value.
|
|
# :snapshot :: If true, snapshot mode will be used for this query.
|
|
# Snapshot mode assures no duplicates are returned, or
|
|
# objects missed, which were preset at both the start and
|
|
# end of the query's execution. For details see
|
|
# http://www.mongodb.org/display/DOCS/How+to+do+Snapshotting+in+the+Mongo+Database
|
|
# :timeout :: When +true+ (default), the returned cursor will be subject to
|
|
# the normal cursor timeout behavior of the mongod process.
|
|
# When +false+, the returned cursor will never timeout. Note
|
|
# that disabling timeout will only work when #find is invoked
|
|
# with a block. This is to prevent any inadvertant failure to
|
|
# close the cursor, as the cursor is explicitly closed when
|
|
# block code finishes.
|
|
def find(selector={}, options={})
|
|
fields = options.delete(:fields)
|
|
fields = ["_id"] if fields && fields.empty?
|
|
skip = options.delete(:offset) || nil
|
|
if !skip.nil?
|
|
warn "the :offset option to find is deprecated and will be removed. please use :skip instead"
|
|
end
|
|
skip = options.delete(:skip) || skip || 0
|
|
limit = options.delete(:limit) || 0
|
|
sort = options.delete(:sort)
|
|
hint = options.delete(:hint)
|
|
snapshot = options.delete(:snapshot)
|
|
if options[:timeout] == false && !block_given?
|
|
raise ArgumentError, "Timeout can be set to false only when #find is invoked with a block."
|
|
end
|
|
timeout = block_given? ? (options.delete(:timeout) || true) : true
|
|
if hint
|
|
hint = normalize_hint_fields(hint)
|
|
else
|
|
hint = @hint # assumed to be normalized already
|
|
end
|
|
raise RuntimeError, "Unknown options [#{options.inspect}]" unless options.empty?
|
|
|
|
cursor = Cursor.new(self, :selector => selector, :fields => fields, :skip => skip, :limit => limit,
|
|
:order => sort, :hint => hint, :snapshot => snapshot, :timeout => timeout)
|
|
if block_given?
|
|
yield cursor
|
|
cursor.close()
|
|
nil
|
|
else
|
|
cursor
|
|
end
|
|
end
|
|
|
|
# Get a single object from the database.
|
|
#
|
|
# Raises TypeError if the argument is of an improper type. Returns a
|
|
# single document (hash), or nil if no result is found.
|
|
#
|
|
# :spec_or_object_id :: a hash specifying elements which must be
|
|
# present for a document to be included in the result set OR an
|
|
# instance of ObjectID to be used as the value for an _id query.
|
|
# if nil an empty spec, {}, will be used.
|
|
# :options :: options, as passed to Collection#find
|
|
def find_one(spec_or_object_id=nil, options={})
|
|
spec = case spec_or_object_id
|
|
when nil
|
|
{}
|
|
when ObjectID
|
|
{:_id => spec_or_object_id}
|
|
when Hash
|
|
spec_or_object_id
|
|
else
|
|
raise TypeError, "spec_or_object_id must be an instance of ObjectID or Hash, or nil"
|
|
end
|
|
find(spec, options.merge(:limit => -1)).next_object
|
|
end
|
|
|
|
# Save a document in this collection.
|
|
#
|
|
# If +to_save+ already has an '_id' then an update (upsert) operation
|
|
# is performed and any existing document with that _id is overwritten.
|
|
# Otherwise an insert operation is performed. Returns the _id of the
|
|
# saved document.
|
|
#
|
|
# :to_save :: the document (a hash) to be saved
|
|
#
|
|
# Options:
|
|
# :safe :: if true, check that the save succeeded. OperationFailure
|
|
# will be raised on an error. Checking for safety requires an extra
|
|
# round-trip to the database
|
|
def save(to_save, options={})
|
|
if id = to_save[:_id] || to_save['_id']
|
|
update({:_id => id}, to_save, :upsert => true, :safe => options.delete(:safe))
|
|
id
|
|
else
|
|
insert(to_save, :safe => options.delete(:safe))
|
|
end
|
|
end
|
|
|
|
# Insert a document(s) into this collection.
|
|
#
|
|
# "<<" is aliased to this method. Returns the _id of the inserted
|
|
# document or a list of _ids of the inserted documents. The object(s)
|
|
# may have been modified by the database's PK factory, if it has one.
|
|
#
|
|
# :doc_or_docs :: a document (as a hash) or Array of documents to be
|
|
# inserted
|
|
#
|
|
# Options:
|
|
# :safe :: if true, check that the insert succeeded. OperationFailure
|
|
# will be raised on an error. Checking for safety requires an extra
|
|
# round-trip to the database
|
|
def insert(doc_or_docs, options={})
|
|
doc_or_docs = [doc_or_docs] unless doc_or_docs.is_a?(Array)
|
|
doc_or_docs.collect! { |doc| @pk_factory.create_pk(doc) }
|
|
result = insert_documents(doc_or_docs, @name, true, options[:safe])
|
|
result.size > 1 ? result : result.first
|
|
end
|
|
alias_method :<<, :insert
|
|
|
|
# Remove all records from this collection.
|
|
# If +selector+ is specified, only matching documents will be removed.
|
|
#
|
|
# Remove all records from the collection:
|
|
# @collection.remove
|
|
# @collection.remove({})
|
|
#
|
|
# Remove only records that have expired:
|
|
# @collection.remove({:expire => {'$lte' => Time.now}})
|
|
def remove(selector={})
|
|
message = ByteBuffer.new
|
|
message.put_int(0)
|
|
BSON.serialize_cstr(message, "#{@db.name}.#{@name}")
|
|
message.put_int(0)
|
|
message.put_array(BSON_SERIALIZER.serialize(selector, false).unpack("C*"))
|
|
@db.send_message_with_operation(Mongo::Constants::OP_DELETE, message,
|
|
"db.#{@db.name}.remove(#{selector.inspect})")
|
|
end
|
|
|
|
# Remove all records.
|
|
# DEPRECATED: please use Collection#remove instead.
|
|
def clear
|
|
warn "Collection#clear is deprecated. Please use Collection#remove instead."
|
|
remove({})
|
|
end
|
|
|
|
# Update a single document in this collection.
|
|
#
|
|
# :selector :: a hash specifying elements which must be present for a document to be updated. Note:
|
|
# the update command currently updates only the first document matching the
|
|
# given selector. If you want all matching documents to be updated, be sure
|
|
# to specify :multi => true.
|
|
# :document :: a hash specifying the fields to be changed in the
|
|
# selected document, or (in the case of an upsert) the document to
|
|
# be inserted
|
|
#
|
|
# Options:
|
|
# :upsert :: if true, perform an upsert operation
|
|
# :multi :: update all documents matching the selector, as opposed to
|
|
# just the first matching document. Note: only works in 1.1.3 or later.
|
|
# :safe :: if true, check that the update succeeded. OperationFailure
|
|
# will be raised on an error. Checking for safety requires an extra
|
|
# round-trip to the database
|
|
def update(selector, document, options={})
|
|
message = ByteBuffer.new
|
|
message.put_int(0)
|
|
BSON.serialize_cstr(message, "#{@db.name}.#{@name}")
|
|
update_options = 0
|
|
update_options += 1 if options[:upsert]
|
|
update_options += 2 if options[:multi]
|
|
message.put_int(update_options)
|
|
message.put_array(BSON_SERIALIZER.serialize(selector, false).unpack("C*"))
|
|
message.put_array(BSON_SERIALIZER.serialize(document, false).unpack("C*"))
|
|
if options[:safe]
|
|
@db.send_message_with_safe_check(Mongo::Constants::OP_UPDATE, message,
|
|
"db.#{@name}.update(#{selector.inspect}, #{document.inspect})")
|
|
else
|
|
@db.send_message_with_operation(Mongo::Constants::OP_UPDATE, message,
|
|
"db.#{@name}.update(#{selector.inspect}, #{document.inspect})")
|
|
end
|
|
end
|
|
|
|
# Create a new index. +field_or_spec+
|
|
# should be either a single field name or a Array of [field name,
|
|
# direction] pairs. Directions should be specified as
|
|
# Mongo::ASCENDING or Mongo::DESCENDING.
|
|
# +unique+ is an optional boolean indicating whether this index
|
|
# should enforce a uniqueness constraint.
|
|
def create_index(field_or_spec, unique=false)
|
|
field_h = OrderedHash.new
|
|
if field_or_spec.is_a?(String) || field_or_spec.is_a?(Symbol)
|
|
field_h[field_or_spec.to_s] = 1
|
|
else
|
|
field_or_spec.each { |f| field_h[f[0].to_s] = f[1] }
|
|
end
|
|
name = generate_index_names(field_h)
|
|
sel = {
|
|
:name => name,
|
|
:ns => "#{@db.name}.#{@name}",
|
|
:key => field_h,
|
|
:unique => unique }
|
|
insert_documents([sel], Mongo::DB::SYSTEM_INDEX_COLLECTION, false)
|
|
name
|
|
end
|
|
|
|
# Drop index +name+.
|
|
def drop_index(name)
|
|
@db.drop_index(@name, name)
|
|
end
|
|
|
|
# Drop all indexes.
|
|
def drop_indexes
|
|
# just need to call 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
|
|
|
|
# Perform a query similar to an SQL group by operation.
|
|
#
|
|
# Returns an array of grouped items.
|
|
#
|
|
# :keys :: Array of fields to group by
|
|
# :condition :: specification of rows to be considered (as a 'find'
|
|
# query specification)
|
|
# :initial :: initial value of the aggregation counter object
|
|
# :reduce :: aggregation function as a JavaScript string
|
|
# :command :: if true, run the group as a command instead of in an
|
|
# eval - it is likely that this option will eventually be
|
|
# deprecated and all groups will be run as commands
|
|
def group(keys, condition, initial, reduce, command=false)
|
|
if command
|
|
hash = {}
|
|
keys.each do |k|
|
|
hash[k] = 1
|
|
end
|
|
|
|
case reduce
|
|
when Code
|
|
else
|
|
reduce = Code.new(reduce)
|
|
end
|
|
|
|
result = @db.db_command({"group" =>
|
|
{
|
|
"ns" => @name,
|
|
"$reduce" => reduce,
|
|
"key" => hash,
|
|
"cond" => condition,
|
|
"initial" => initial}})
|
|
if result["ok"] == 1
|
|
return result["retval"]
|
|
else
|
|
raise OperationFailure, "group command failed: #{result['errmsg']}"
|
|
end
|
|
end
|
|
|
|
case reduce
|
|
when Code
|
|
scope = reduce.scope
|
|
else
|
|
scope = {}
|
|
end
|
|
scope.merge!({
|
|
"ns" => @name,
|
|
"keys" => keys,
|
|
"condition" => condition,
|
|
"initial" => initial })
|
|
|
|
group_function = <<EOS
|
|
function () {
|
|
var c = db[ns].find(condition);
|
|
var map = new Map();
|
|
var reduce_function = #{reduce};
|
|
while (c.hasNext()) {
|
|
var obj = c.next();
|
|
|
|
var key = {};
|
|
for (var i = 0; i < keys.length; i++) {
|
|
var k = keys[i];
|
|
key[k] = obj[k];
|
|
}
|
|
|
|
var aggObj = map.get(key);
|
|
if (aggObj == null) {
|
|
var newObj = Object.extend({}, key);
|
|
aggObj = Object.extend(newObj, initial);
|
|
map.put(key, aggObj);
|
|
}
|
|
reduce_function(obj, aggObj);
|
|
}
|
|
return {"result": map.values()};
|
|
}
|
|
EOS
|
|
return @db.eval(Code.new(group_function, scope))["result"]
|
|
end
|
|
|
|
# Returns 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.
|
|
# @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]
|
|
def distinct(key)
|
|
raise MongoArgumentError unless [String, Symbol].include?(key.class)
|
|
command = OrderedHash.new
|
|
command[:distinct] = @name
|
|
command[:key] = key.to_s
|
|
|
|
@db.db_command(command)["values"]
|
|
end
|
|
|
|
# Rename this collection.
|
|
#
|
|
# If operating in auth mode, client must be authorized as an admin to
|
|
# perform this operation. Raises +InvalidName+ if +new_name+ is an invalid
|
|
# collection name.
|
|
#
|
|
# :new_name :: new name for this collection
|
|
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 InvalidName, "collection names cannot be empty"
|
|
end
|
|
if new_name.include? "$"
|
|
raise InvalidName, "collection names must not contain '$'"
|
|
end
|
|
if new_name.match(/^\./) or new_name.match(/\.$/)
|
|
raise InvalidName, "collection names must not start or end with '.'"
|
|
end
|
|
|
|
@db.rename_collection(@name, new_name)
|
|
end
|
|
|
|
# Get information on the indexes for the collection +collection_name+.
|
|
# Returns a hash where the keys are index names (as returned by
|
|
# Collection#create_index and the values are lists of [key, direction]
|
|
# pairs specifying the index (as passed to Collection#create_index).
|
|
def index_information
|
|
@db.index_information(@name)
|
|
end
|
|
|
|
# Return a hash containing options that apply to this collection.
|
|
# 'create' will be the collection name. For the other possible keys
|
|
# and values, see DB#create_collection.
|
|
def options
|
|
@db.collections_info(@name).next_object()['options']
|
|
end
|
|
|
|
# Get the number of documents in this collection.
|
|
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 = OrderedHash.new
|
|
hint.to_a.each { |k| h[k] = 1 }
|
|
h
|
|
end
|
|
end
|
|
|
|
private
|
|
|
|
# Sends an 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)
|
|
message = ByteBuffer.new
|
|
message.put_int(0)
|
|
BSON.serialize_cstr(message, "#{@db.name}.#{collection_name}")
|
|
documents.each { |doc| message.put_array(BSON_SERIALIZER.serialize(doc, check_keys).unpack("C*")) }
|
|
if safe
|
|
@db.send_message_with_safe_check(Mongo::Constants::OP_INSERT, message,
|
|
"db.#{collection_name}.insert(#{documents.inspect})")
|
|
else
|
|
@db.send_message_with_operation(Mongo::Constants::OP_INSERT, message,
|
|
"db.#{collection_name}.insert(#{documents.inspect})")
|
|
end
|
|
documents.collect { |o| o[:_id] || o['_id'] }
|
|
end
|
|
|
|
def generate_index_names(spec)
|
|
indexes = []
|
|
spec.each_pair do |field, direction|
|
|
indexes.push("#{field}_#{direction}")
|
|
end
|
|
indexes.join("_")
|
|
end
|
|
end
|
|
end
|