Class: Kongo::Collection

Inherits:
Object
  • Object
show all
Defined in:
lib/kongo.rb

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name) ⇒ Collection

Initialize with a collection name (as symbol), will use that collection name to generate the connection lazily when it is first used, thru the collection callback (must be defined).



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# File 'lib/kongo.rb', line 13

def initialize(name)
  @coll_name = name
  @visible_ivars = []
  @@extensions ||= {}

  if @@extensions[name.to_sym]
    @@extensions[name.to_sym].each do |const|
      extend(const)
    end
  end
end

Class Method Details

.add_extension(collection_name, mod) ⇒ Object

Declare extensions using this method:

Kongo::Collection.add_extension(:collection_name, module)



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# File 'lib/kongo.rb', line 134

def self.add_extension(collection_name, mod)
  ((@@extensions ||= {})[collection_name.to_sym] ||= []) << mod
end

.fetch_collections_using(&block) ⇒ Object

This method must be called statically on the ORM once before being used, so that the ORM knows how to connect to mongo and fetch collections.

A simple usage example might look like this:

class MongoCollectionFetcher
  def self.fetch(name)
    unless @mongo
      @mongo = Mongo::Connection.new
    end
    return @mongo['database'][name.to_s]
  end
end

Kongo::Collection.fetch_collections_using do |n|
  MongoCollectionFetcher.fetch(n)
end



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# File 'lib/kongo.rb', line 97

def self.fetch_collections_using(&block)
  @@collection_fetcher = block
end

Instance Method Details

#coll ⇒ Object

This method returns the Mongo::Collection object for this collection.



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# File 'lib/kongo.rb', line 104

def coll
  return @coll if @coll

  @coll ||= begin
    raise 'Kongo has not been initialized with a collection fetcher.' unless @@collection_fetcher
    @@collection_fetcher.call(@coll_name)
  end
end

#count(*args) ⇒ Object

Count, just forwards to driver.



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# File 'lib/kongo.rb', line 52

def count(*args)
  coll.count(*args)
end

#extend(const) ⇒ Object

This method just adds the extension to the list of extension, for the sake of inspect, and call super:



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# File 'lib/kongo.rb', line 74

def extend(arg)
  super(arg.is_a?(Symbol) ? Extensions::Collections.const_get(arg) : arg)
end

#find(*args) ⇒ Object Also known as: find_many

‘find`, aka. `find_many` returns a Kongo::Cursor wrapping the Mongo cursor.



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# File 'lib/kongo.rb', line 44

def find(*args)
  (c = coll.find(*args)).is_a?(::Mongo::Cursor) ?
    Cursor.new(c, coll) : c
end

#find_by_id(id) ⇒ Object

If passed a legal BSON ObjectId string, will convert to BSON::ObjectId. Otherwise finds by value.



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# File 'lib/kongo.rb', line 36

def find_by_id(id)
  id = BSON::ObjectId(id) if id.is_a?(String) && BSON::ObjectId.legal?(id)
  find_one(_id: id)
end

#find_one(*args) ⇒ Object

When passed a native BSON::ObjectId, it will act as a find_by_id, otherwise, expects a regular query hash. Will return a Kongo::Model.



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# File 'lib/kongo.rb', line 28

def find_one(*args)
  (r = coll.find_one(*args)) ?
    Model.new(r, coll) : r
end

#has?(id) ⇒ Boolean

Verify existence of record by id.

Returns:

  • (Boolean) 


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# File 'lib/kongo.rb', line 58

def has?(id)
  count(:query => {_id: id}) == 1
end

#insert!(hash) ⇒ Object

Insert a record, returns a Model object.



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# File 'lib/kongo.rb', line 64

def insert!(hash)
  coll.insert(hash)
  hash['_id'] = hash.delete(:_id) if hash[:_id]
  Model.new(hash, coll)
end

#inspect ⇒ Object

Inspecting a Mongo Model attempts to only show useful information, such as what its extensions are as well as certain ivars.



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# File 'lib/kongo.rb', line 118

def inspect
  proxy = Object.new
  @visible_ivars.each do |ivar|
    val = instance_variable_get(ivar)
    proxy.instance_variable_set(ivar, val) unless val.nil?
  end
  string = proxy.inspect
  ext_info = @extensions ? '(+ '+@extensions.join(', ')+')' : ''
  string.gsub(/Object:0x[0-9a-f]+/, "Kongo::Collection#{ext_info}:0x#{object_id}")
end