googledatastore Package

googledatastore Package

googledatastore client.

googledatastore.__init__.allocate_ids(request)

See connection.Datastore.allocate_ids.

googledatastore.__init__.begin_transaction(request)

See connection.Datastore.begin_transaction.

googledatastore.__init__.commit(request)

See connection.Datastore.commit.

googledatastore.__init__.get_default_connection()

Return the default datastore connection.

dataset defaults to helper.get_dataset_from_env(), host to os.getenv(‘DATASTORE_HOST’), and credentials to helper.get_credentials_from_env().

Use set_options to override defaults.

googledatastore.__init__.lookup(request)

See connection.Datastore.lookup.

googledatastore.__init__.rollback(request)

See connection.Datastore.rollback.

googledatastore.__init__.run_query(request)

See connection.Datastore.run_query.

googledatastore.__init__.set_options(**kwargs)

Set datastore connection options.

Args:

credentials: oauth2client.Credentials to authorize the connection. dataset: the dataset to send RPCs to. host: the host used to construct the datastore API, default to Google APIs production server.

connection Module

googledatastore connection.

class googledatastore.connection.Datastore(dataset, credentials=None, host=None)

Bases: object

Datastore client connection constructor.

allocate_ids(request)

Allocate ids for incomplete keys.

Args:

request: AllocateIdsRequest proto message.

Returns:

AllocateIdsResponse proto message.

Raises:

RPCError: The underlying RPC call failed with an HTTP error. (See: .response attribute)

begin_transaction(request)

Begin a new transaction.

Args:

request: BeginTransactionRequest proto message.

Returns:

BeginTransactionResponse proto message.

Raises:

RPCError: The underlying RPC call failed with an HTTP error. (See: .response attribute)

commit(request)

Commit a mutation, transaction or mutation in a transaction.

Args:

request: CommitRequest proto message.

Returns:

CommitResponse proto message.

Raises:

RPCError: The underlying RPC call failed with an HTTP error. (See: .response attribute)

lookup(request)

Lookup entities by key.

Args:

request: LookupRequest proto message.

Returns:

LookupResponse proto message.

Raises:

RPCError: The underlying RPC call failed with an HTTP error. (See: .response attribute)

rollback(request)

Rollback a transaction.

Args:

request: RollbackRequest proto message.

Returns:

RollbackResponse proto message.

Raises:

RPCError: The underlying RPC call failed with an HTTP error. (See: .response attribute)

run_query(request)

Query for entities.

Args:

request: RunQueryRequest proto message.

Returns:

RunQueryResponse proto message.

Raises:

RPCError: The underlying RPC call failed with an HTTP error. (See: .response attribute)

exception googledatastore.connection.Error

Bases: exceptions.Exception

A Datastore service error occured.

exception googledatastore.connection.HTTPError

Bases: googledatastore.connection.Error

An HTTP error occured.

response = None

exception googledatastore.connection.RPCError(method, response, content)

Bases: googledatastore.connection.HTTPError

The Datastore RPC failed.

method = None

reason = None

exception googledatastore.connection.AuthError

Bases: googledatastore.connection.Error

Authentication failed.

exception googledatastore.connection.BadArgumentError

Bases: googledatastore.connection.Error

Argument validation failed.

datastore_v1_pb2 Module

helper Module

googledatastore helper.

googledatastore.helper.get_credentials_from_env()

Get datastore credentials from the environment.

Try and fallback on the following credentials in that order: - Google APIs Signed JWT credentials based on DATASTORE_SERVICE_ACCOUNT and DATASTORE_PRIVATE_KEY_FILE environment variables - Compute Engine service account - No credentials (development server)

Returns:

datastore credentials.

googledatastore.helper.add_key_path(key_proto, *path_elements)

Add path elements to the given datastore.Key proto message.

Args:

key_proto: datastore.Key proto message. path_elements: list of ancestors to add to the key. (kind1, id1/name1, ..., kindN, idN/nameN), the last 2 elements represent the entity key, if no terminating id/name: they key will be an incomplete key.

Raises:

TypeError: the given id or name has the wrong type.

Returns:

the same datastore.Key.

Usage:

>>> add_key_path(key_proto, 'Kind', 'name')  # no parent, with name
datastore.Key(...)
>>> add_key_path(key_proto, 'Kind2', 1)  # no parent, with id
datastore.Key(...)
>>> add_key_path(key_proto, 'Kind', 'name', 'Kind2', 1)  # parent, complete
datastore.Key(...)
>>> add_key_path(key_proto, 'Kind', 'name', 'Kind2')  # parent, incomplete
datastore.Key(...)

googledatastore.helper.add_properties(entity_proto, property_dict, indexed=None)

Add values to the given datastore.Entity proto message.

Args:

entity_proto: datastore.Entity proto message. property_dict: a dictionary from property name to either a python object or

datastore.Value.

indexed: if the property values should be indexed. None leaves indexing as

is (defaults to True if value is a python object).

Usage:

>>> add_properties(proto, {'foo': u'a', 'bar': [1, 2]})

Raises:

TypeError: if a given property value type is not supported.

googledatastore.helper.set_property(property_proto, name, value, indexed=None)

Set property value in the given datastore.Property proto message.

Args:

property_proto: datastore.Property proto message. name: name of the property. value: python object or datastore.Value. indexed: if the value should be indexed. None leaves indexing as is

(defaults to True if value is a python object).

Usage:

>>> set_property(property_proto, 'foo', u'a')

Raises:

TypeError: if the given value type is not supported.

googledatastore.helper.set_value(value_proto, value, indexed=None)

Set the corresponding datastore.Value _value field for the given arg.

Args:

value_proto: datastore.Value proto message. value: python object or datastore.Value. (unicode value will set a

datastore string value, str value will set a blob string value). Undefined behavior if value is/contains value_proto.

indexed: if the value should be indexed. None leaves indexing as is

(defaults to True if value is not a Value message).

Raises:

TypeError: if the given value type is not supported.

googledatastore.helper.get_value(value_proto)

Gets the python object equivalent for the given value proto.

Args:

value_proto: datastore.Value proto message.

Returns:

the corresponding python object value. timestamps are converted to datetime, and datastore.Value is returned for blob_key_value.

googledatastore.helper.get_property_dict(entity_proto)

Convert datastore.Entity to a dict of property name -> datastore.Value.

Args:

entity_proto: datastore.Entity proto message.

Usage:

>>> get_property_dict(entity_proto)
{'foo': {string_value='a'}, 'bar': {integer_value=2}}

Returns:

dict of entity properties.

googledatastore.helper.set_kind(query_proto, kind)

Set the kind constraint for the given datastore.Query proto message.

googledatastore.helper.add_property_orders(query_proto, *orders)

Add ordering constraint for the given datastore.Query proto message.

Args:

query_proto: datastore.Query proto message. orders: list of propertype name string, default to ascending order and set descending if prefixed by ‘-‘.

Usage:

>>> add_property_orders(query_proto, 'foo')  # sort by foo asc
>>> add_property_orders(query_proto, '-bar')  # sort by bar desc

googledatastore.helper.add_projection(query_proto, *projection)

Add projection properties to the given datatstore.Query proto message.

googledatastore.helper.set_property_filter(filter_proto, name, op, value)

Set property filter contraint in the given datastore.Filter proto message.

Args:

filter_proto: datastore.Filter proto message name: property name op: datastore.PropertyFilter.Operation value: property value

Returns:

the same datastore.Filter.

Usage:

>>> set_property_filter(filter_proto, 'foo',
...   datastore.PropertyFilter.EQUAL, 'a')  # WHERE 'foo' = 'a'

googledatastore.helper.set_composite_filter(filter_proto, op, *filters)

Set composite filter contraint in the given datastore.Filter proto message.

Args:

filter_proto: datastore.Filter proto message op: datastore.CompositeFilter.Operation filters: vararg list of datastore.Filter

Returns:

the same datastore.Filter.

Usage:

>>> set_composite_filter(filter_proto, datastore.CompositeFilter.AND,
...   set_property_filter(datastore.Filter(), ...),
...   set_property_filter(datastore.Filter(), ...)) # WHERE ... AND ...

googledatastore.helper.to_timestamp_usec(dt)

Convert datetime to microsecond timestamp.

Args:

dt: a timezone naive datetime.

Returns:

a microsecond timestamp as a long.

Raises:

TypeError: if a timezone aware datetime was provided.

googledatastore.helper.from_timestamp_usec(timestamp)

Convert microsecond timestamp to datetime.