metadata

All relations in Mongoid contain metadata that holds information about the relation in question, and is a valuable tool for third party developers to use to extend Mongoid.

You can access the metadata of the relation in a few different ways.

# Get the metadata for a named relation from the class or document.
Model.reflect_on_association(:relation_name)
model.reflect_on_association(:relation_name)

# Get the metadata that the current object has in its relation.
model.metadata

# Get the metadata with a specific relation itself on a specific
# document.
person.addresses.metadata

the metadata object

The metadata object itself contains more information than one might know what to do with.

• Metadata#class_name
• Metadata#embedded?
• Metadata#extension
• Metadata#foreign_key
• Metadata#foreign_key_default
• Metadata#foreign_key_setter
• Metadata#indexed?
• Metadata#inverse
• Metadata#inverse_foreign_key
• Metadata#inverse_klass
• Metadata#inverse_setter
• Metadata#inverse_type
• Metadata#inverse_type_setter
• Metadata#key
• Metadata#klass
• Metadata#macro
• Metadata#polymorphic?
• Metadata#setter
• Metadata#stores_foreign_key?
• Metadata#validate?