Code snippets for http://ryanfunduk.com/mongorb

1.rb

class Document
  class NotFound < StandardError; end
  class InvalidFieldName < StandardError; end

  @@__cache = {}
  @@connection = nil
  @@database_name = nil
  @@database = nil

  def self.cached
    class_eval %(class << self; @@__cache['#{name}'] = {}; end)
  end

  def self.references( obj, klass=nil )
    obj = obj.to_s
    klass ||= obj.capitalize
    class_eval %{
      def #{obj}
        from_extra '#{obj}', #{klass}
      end
      def #{obj}=( val )
        @doc['#{obj}'] = val.id
        @extra.delete '#{obj}'
        #{obj}
      end
    }
  end

  def self.field( name )
    raise InvalidFieldName if self.instance_methods.include?( name.to_s )
    class_eval %{
      def #{name};@doc['#{name}'];end
      def #{name}=( val );@doc['#{name}'] = val;end
    }
  end

  def self.connection=(value, db_name)
    raise "You must supply a database name!" unless db_name.is_a? String
    @@database_name = db_name
    @@connection = value
  end

  def self.connection
    @@connection
  end

  def self.database
    @@database ||= self.connection.db( @@database_name )
  end

  def initialize( doc, no_save=false )
    raise NotFound unless doc.is_a? Hash
    @doc = doc
    @extra = {}
    @extra['no_save'] = no_save
  end

  def []( field )
    @doc.has_key?( field ) ? @doc[field] : @extra[field]
  end
  def []=( field, value )
    if @extra.has_key?( field )
      @extra[field] = value
    else
      @doc[field] = value
    end
  end

  def ==( other )
    id == other.id rescue false
  end

  def id
    @doc['_id']
  end

  def merge!( hash )
    @doc.merge! hash.stringify_keys
  end

  def save
    raise "Saving is disabled for light model instances!" if @extra['no_save']
    collection.save( @doc )
    self
  end

  def save!
    collection.insert( @doc )
    self
  end

  def delete
    collection.remove( { '_id' => @doc['_id'] } )
  end

  def self.collection( override=nil )
    coll = override || self.name.tableize
    self.database.collection( coll )
  end

  def collection
    self.class.collection
  end

  def self.find( query, options={}, bust_cache=false )
    query = { '_id' => query } unless query.is_a? Hash

    if @@__cache.has_key? name
      query_hash = (query.inspect + options.inspect).hash
      @@__cache[name][query_hash] = nil if bust_cache
      @@__cache[name][query_hash] ||= self.new( collection.find( query, options ).next_document )
    else
      self.new( collection.find( query, options ).next_document )
    end
  end

  def self.all( query={}, options={}, sort=nil )
    no_save = options.delete( :no_save ) || false
    result = collection.find( query, options ).to_a.collect do |d|
      self.new( d, no_save )
    end
    sort = '_id' if sort == true # default sort key is _id
    result = result.sort { |a,b| a[sort] <=> b[sort] } if sort
    result
  end

  private
    def from_extra( field, klass )
      return nil unless @doc[field]
      if @extra.has_key? field
        @extra[field]
      else
        @extra[field] = klass.find( @doc[field] )
      end
    end
end