mongomapper $where examples

require 'mongo_mapper'
require 'spec'
require 'log4r'
require 'versionomy'

# Logger used for logging MongoDB database commands
Log4r::Logger.new('TMP')
Log4r::Logger['TMP'].outputters = Log4r::StdoutOutputter.new(:console)
Log4r::Outputter[:console].formatter  = Log4r::PatternFormatter.new(:pattern => "%m")
Log4r::Logger['TMP'].level = Log4r::DEBUG

# Monkey patch the driver to get buildinfo which contains the version of the MongoDB server
# The version is checked because saving functions on the server requires MongoDB 1.1.1 or newer
module Mongo
  class Admin
    def buildinfo
      oh = OrderedHash.new
      oh[:buildinfo] = 1
      doc = @db.db_command(oh)
      raise "Error with buildinfo command: #{doc.inspect}" unless @db.ok?(doc)
      doc
    end
  end
end

# connect with a logger!  Whoooop!  Great feature
MongoMapper.connection = Mongo::Connection.new('localhost', nil, :logger => Log4r::Logger['TMP'])

# grab the version from the admin database
MongoMapper.database = 'admin'
mongo_version = Versionomy.parse(MongoMapper.database.admin.buildinfo['version'])

# now switch to our testing database
MongoMapper.database = 'test'

# test model
class Test
  include MongoMapper::Document
  key :first, Integer
  key :second, Integer
end

 
describe '$where usage' do
  before :all do
    Log4r::Logger['TMP'].debug { 'writing server-side functions' }
    # remove any functions saved on the server
    MongoMapper.database.eval(Mongo::Code.new('db.system.js.remove({});'))
  end
 
  before :each do
    Log4r::Logger['TMP'].debug { 'setting up initial database contents' }
    # clean database for each test
    Test.collection.clear
    Test.create(:first => 10, :second => 15)
    Test.create(:first => 17, :second => 23)
  end
  
  it "should run js evals" do
    Log4r::Logger['TMP'].debug { 'should run js evals' }
    MongoMapper.database.eval(Mongo::Code.new('function(){ return 11 + 6; }')).should == 17
    MongoMapper.database.eval(Mongo::Code.new('function( x ){ return 10 + x; }'), 7).should == 17
    # notice that the Mongo::Code.new() is not necessary
    MongoMapper.database.eval('function( z ){ return 17 + z; }', 5).should == 22
  end

  it "should run server-side functions" do
    Log4r::Logger['TMP'].debug { 'should run server-side functions' }
    Test.count.should == 2
    Test.all(:conditions => {'$where' => Mongo::Code.new("this.first + this.second > 30;")}).size.should == 1
    Test.all(:conditions => {'$where' => "this.first + this.second > 30;"}).size.should == 1
    Test.all(:conditions => {:first => {'$gt' => 15}}).size.should == 1

    # can't get the function(x){...} notation to work
    # Test.all(:conditions => {'$where' => Mongo::Code.new("function( a ){ return a.first > 15; }")}).size.should == 1
    #
    # RuntimeError in 'Wishful Thinking should run server-side functions'
    # error on invocation of $where function:
    # JS Error: TypeError: a has no properties nofile_b:0
    #
    # server reports:
    # Sat Oct 10 01:06:56 tmp.tests  Caught Assertion in runQuery ns:tmp.tests massert:error on invocation of $where function:
    # JS Error: TypeError: a has no properties nofile_b:0
  end

  it "should store and run server-side functions" do
    Log4r::Logger['TMP'].debug { 'should store and run server-side functions' }
    
    # storing functions on the server side requires MongoDB 1.1.1 or newer
    minimum_mongo_version = Versionomy.parse('1.1.1')
    (mongo_version <=> minimum_mongo_version).should >= 0
    
    # with or without Mongo::Code.new
    MongoMapper.database.eval(Mongo::Code.new('db.system.js.count();')).should == 0
    MongoMapper.database.eval('db.system.js.count();').should == 0
  
    # need to add the following server-side function:
    # note, can be either with or without Mongo::Code.new
    javascript = "db.system.js.insert( { _id : 'combine', value : function( a ) " + 
                 "{ return a.first + a.second; } } );"
    MongoMapper.database.eval(javascript)
    MongoMapper.database.eval('db.system.js.count();').should == 1
    
    # just making sure we have the two documents
    Test.count.should == 2

    # use the function stored on the servera
    # with or without Mongo::Code.new
    Test.all(:conditions => {"$where" => Mongo::Code.new("combine(this) > 30")}).size.should == 1
    min = 30
    Test.all(:conditions => {"$where" => "combine(this) > #{min}"}).size.should == 1
  end
  
end