Python

0.4.0

Entities

Class for representing a single entity in the Cloud Datastore.

class gcloud.datastore.entity.Entity(key=None, exclude_from_indexes=())

Bases: dict

Entities are akin to rows in a relational database

An entity storing the actual instance of data.

Each entity is officially represented with a gcloud.datastore.key.Key class, however it is possible that you might create an Entity with only a partial Key (that is, a Key with a Kind, and possibly a parent, but without an ID). In such a case, the datastore service will automatically assign an ID to the partial key.

Entities in this API act like dictionaries with extras built in that allow you to delete or persist the data stored on the entity.

Entities are mutable and act like a subclass of a dictionary. This means you could take an existing entity and change the key to duplicate the object.

Use gcloud.datastore.get() to retrieve an existing entity.

>>> datastore.get(key)
<Entity[{'kind': 'EntityKind', id: 1234}] {'property': 'value'}>

You can the set values on the entity just like you would on any other dictionary.

>>> entity['age'] = 20
>>> entity['name'] = 'JJ'
>>> entity
<Entity[{'kind': 'EntityKind', id: 1234}] {'age': 20, 'name': 'JJ'}>

And you can convert an entity to a regular Python dictionary with the dict builtin:

>>> dict(entity)
{'age': 20, 'name': 'JJ'}

Note

When saving an entity to the backend, values which are “text” (unicode in Python2, str in Python3) will be saved using the ‘text_value’ field, after being encoded to UTF-8. When retrieved from the back-end, such values will be decoded to “text” again. Values which are “bytes” (str in Python2, bytes in Python3), will be saved using the ‘blob_value’ field, without any decoding / encoding step.

Parameters:

• key (gcloud.datastore.key.Key) – Optional key to be set on entity. Required for gcloud.datastore.put()
• exclude_from_indexes (tuple of string) – Names of fields whose values are not to be indexed for this entity.

exclude_from_indexes

Names of fields which are not to be indexed for this entity.

Return type:sequence of field names

kind

Get the kind of the current entity.

Note

This relies entirely on the gcloud.datastore.key.Key set on the entity. That means that we’re not storing the kind of the entity at all, just the properties and a pointer to a Key which knows its Kind.