tensorstore.KvStore - TensorStore

class tensorstore.KvStore

Key-value store that maps an ordered set of byte string keys to byte string values.

This is used as the storage interface for most of the TensorStore drivers.

The actual storage mechanism is determined by the driver.

Example

>>> store = await ts.KvStore.open({'driver': 'memory'})
>>> await store.write(b'a', b'value')
KvStore.TimestampedStorageGeneration(...)
>>> await store.read(b'a')
KvStore.ReadResult(state='value', value=b'value', stamp=KvStore.TimestampedStorageGeneration(...))
>>> await store.read(b'b')
KvStore.ReadResult(state='missing', value=b'', stamp=KvStore.TimestampedStorageGeneration(...))
>>> await store.list()
[b'a']

By default, operations are non-transactional, but transactional operations are also supported:

>>> txn = ts.Transaction()
>>> store.with_transaction(txn)[b'a']
b'value'
>>> store.with_transaction(txn)[b'a'] = b'new value'
>>> store.with_transaction(txn)[b'a']
b'new value'
>>> store[b'a']
b'value'
>>> txn.commit_sync()
>>> store[b'a']
b'new value'

Classes¶

class Spec: Parsed representation of a JSON key-value store specification.

class KeyRange: Half-open interval of byte string keys, according to lexicographical order.

class TimestampedStorageGeneration: Specifies a storage generation identifier and a timestamp.

class ReadResult: Specifies the result of a read operation.

Constructors¶

static open(spec: KvStore.Spec | Any, *, ...) → Future[KvStore]: Opens a key-value store.

Accessors¶

path : str: Path prefix within the base key-value store.

url : str: URL representation of the key-value store specification.

base : KvStore | None: Underlying key-value store, if this is a key-value store adapter.

spec(*, retain_context: bool | None = None, ...) → KvStore.Spec: Spec that may be used to re-open or re-create the key-value store.

copy() → KvStore: Returns a copy of the key-value store.

I/O¶

list(...) → Future[list[bytes]]: Lists the keys in the key-value store.

read(key: str, *, ...) → Future[KvStore.ReadResult]: Reads the value of a single key.

write(key: str, ...) → Future[KvStore.TimestampedStorageGeneration]: Writes or deletes a single key.

delete_range(range: KvStore.KeyRange) → Future[None]: Deletes a key range.

experimental_copy_range_to(target: KvStore, ...) → Future[None]: Copies a range of keys.

Synchronous I/O¶

__getitem__(key: str) → bytes: Synchronously reads the value of a single key.

__setitem__(key: str, value: str | None): Synchronously writes the value of a single key.

__delitem__(key: str) → None: Synchronously deletes a single key.

Operators¶

__add__(suffix: str) → KvStore: Returns a key-value store with the suffix appended to the path.

__truediv__(component: str) → KvStore: Returns a key-value store with an additional path component joined to the path.

Transactions¶

transaction : Transaction | None: Transaction bound to this key-value store.

with_transaction(transaction: Transaction | None) → KvStore: Returns a transaction-bound view of this key-value store.

String representation¶

__repr__() → str: Returns a string representation based on the JSON representation.