proxystore.store¶
The ProxyStore Store
interface.
Store
¶
Store(
name: str,
connector: ConnectorT,
*,
serializer: SerializerT | None = None,
deserializer: DeserializerT | None = None,
cache_size: int = 16,
metrics: bool = False,
populate_target: bool = True,
register: bool = False
)
Bases: Generic[ConnectorT]
Key-value store interface for proxies.
Tip
A Store
instance can be used as a
context manager which will automatically call
close()
on exit.
Warning
The default value of populate_target=True
can cause unexpected
behavior when providing custom serializer/deserializers because
neither the serializer nor deserializer will be applied to the target
object being cached in the resulting Proxy
.
In this example, the serialized data_bytes
was populated as the
target object in the resulting proxy so the proxy looks like a proxy
of bytes rather than the intended list of integers. To fix this, set
populate_target=False
so the custom deserializer is correctly
applied to data_bytes
when the proxy is resolved.
Note
This class is generally thread-safe, with cache access and connector operations guarded by a lock that is local to each store instance.
Warning
This class cannot be pickled. If you need to recreate a
Store
within another process, share
a StoreConfig
, a serializable
and pickle-compatbile type, that can be created using
Store.config()
.
To reconstruct the instance from the config, use
Store.from_config()
or
get_or_create_store()
.
Parameters:
-
name
(str
) –Name of the store instance.
-
connector
(ConnectorT
) –Connector instance to use for object storage.
-
serializer
(SerializerT | None
, default:None
) –Optional callable which serializes the object. If
None
, the default serializer (serialize()
) will be used. -
deserializer
(DeserializerT | None
, default:None
) –Optional callable used by the factory to deserialize the byte string. If
None
, the default deserializer (deserialize()
) will be used. -
cache_size
(int
, default:16
) –Size of LRU cache (in # of objects). If 0, the cache is disabled. The cache is local to the Python process.
-
metrics
(bool
, default:False
) –Enable recording operation metrics.
-
populate_target
(bool
, default:True
) –Set the default value of
populate_target
for proxy methods of the store. -
register
(bool
, default:False
) –Register the store instance after initialization.
Raises:
-
ValueError
–If
cache_size
is less than zero. -
StoreExistsError
–If
register=True
and a store withname
already exists.
Source code in proxystore/store/base.py
close
¶
Close the connector associated with the store.
This will (1) close the connector and (2) unregister the store if
register=True
was set during initialization.
Warning
This method should only be called at the end of the program when the store will no longer be used, for example once all proxies have been resolved.
Parameters:
-
args
(Any
, default:()
) –Positional arguments to pass to
Connector.close()
. -
kwargs
(Any
, default:{}
) –Keyword arguments to pass to
Connector.close()
.
Source code in proxystore/store/base.py
config
¶
config() -> StoreConfig
Get the store configuration.
Returns:
-
StoreConfig
–Store configuration.
Source code in proxystore/store/base.py
from_config
classmethod
¶
from_config(config: StoreConfig) -> Store[Any]
Create a new store instance from a configuration.
Parameters:
-
config
(StoreConfig
) –Configuration returned by
.config()
.
Returns:
Source code in proxystore/store/base.py
future
¶
future(
*,
evict: bool = False,
serializer: SerializerT | None = None,
deserializer: DeserializerT | None = None,
polling_interval: float = 1,
polling_backoff_factor: float = 1,
polling_interval_limit: float | None = None,
polling_timeout: float | None = None
) -> Future[T]
Create a future to an object.
Example
from proxystore.connectors.file import FileConnector
from proxystore.store import Store
from proxystore.store.future import Future
def remote_foo(future: Future) -> None:
# Computation that generates a result value needed by
# the remote_bar function.
future.set_result(...)
def remote_bar(data: Any) -> None:
# Function uses data, which is a proxy, as normal, blocking
# until the remote_foo function has called set_result.
...
with Store('future-example', FileConnector(...)) as store:
future = store.future()
# The invoke_remove function invokes a provided function
# on a remote process. For example, this could be a serverless
# function execution.
foo_result_future = invoke_remote(remote_foo, future)
bar_result_future = invoke_remote(remote_bar, future.proxy())
foo_result_future.result()
bar_result_future.result()
Warning
This method only works if the connector
is of type
DeferrableConnector
.
Warning
This method and the
Future.proxy()
are experimental features and may change in future releases.
Parameters:
-
evict
(bool
, default:False
) –If a proxy returned by
Future.proxy()
should evict the object once resolved. -
serializer
(SerializerT | None
, default:None
) –Optionally override the default serializer for the store instance.
-
deserializer
(DeserializerT | None
, default:None
) –Optionally override the default deserializer for the store instance.
-
polling_interval
(float
, default:1
) –Initial seconds to sleep between polling the store for the object.
-
polling_backoff_factor
(float
, default:1
) –Multiplicative factor applied to the polling_interval applied after each unsuccessful poll.
-
polling_interval_limit
(float | None
, default:None
) –Maximum polling interval allowed. Prevents the backoff factor from increasing the current polling interval to unreasonable values.
-
polling_timeout
(float | None
, default:None
) –Optional maximum number of seconds to poll for. If the timeout is reached an error is raised.
Returns:
-
Future[T]
–Future which can be used to get the result object at a later time or create a proxy which will resolve to the result of the future.
Raises:
-
NotImplementedError
–If the
connector
is not of typeDeferrableConnector
.
Source code in proxystore/store/base.py
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|
evict
¶
evict(key: ConnectorKeyT) -> None
Evict the object associated with the key.
Parameters:
-
key
(ConnectorKeyT
) –Key associated with object to evict.
Source code in proxystore/store/base.py
exists
¶
exists(key: ConnectorKeyT) -> bool
Check if an object associated with the key exists.
Parameters:
-
key
(ConnectorKeyT
) –Key potentially associated with stored object.
Returns:
-
bool
–If an object associated with the key exists.
Source code in proxystore/store/base.py
get
¶
get(
key: ConnectorKeyT,
*,
deserializer: DeserializerT | None = None,
default: object | None = None
) -> Any | None
Get the object associated with the key.
Parameters:
-
key
(ConnectorKeyT
) –Key associated with the object to retrieve.
-
deserializer
(DeserializerT | None
, default:None
) –Optionally override the default deserializer for the store instance.
-
default
(object | None
, default:None
) –An optional value to be returned if an object associated with the key does not exist.
Returns:
-
Any | None
–Object or
None
if the object does not exist.
Raises:
-
SerializationError
–If an exception is caught when deserializing the object associated with the key.
Source code in proxystore/store/base.py
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is_cached
¶
is_cached(key: ConnectorKeyT) -> bool
Check if an object associated with the key is cached locally.
Parameters:
-
key
(ConnectorKeyT
) –Key potentially associated with stored object.
Returns:
-
bool
–If the object is cached.
Source code in proxystore/store/base.py
proxy
¶
proxy(
obj: T | NonProxiableT,
*,
evict: bool = False,
lifetime: Lifetime | None = None,
serializer: SerializerT | None = None,
deserializer: DeserializerT | None = None,
populate_target: bool | None = None,
skip_nonproxiable: bool = False,
**kwargs: Any
) -> Proxy[T] | NonProxiableT
Create a proxy that will resolve to an object in the store.
Parameters:
-
obj
(T | NonProxiableT
) –The object to place in store and return a proxy for.
-
evict
(bool
, default:False
) –If the proxy should evict the object once resolved. Mutually exclusive with the
lifetime
parameter. -
lifetime
(Lifetime | None
, default:None
) –Attach the proxy to this lifetime. The object associated with the proxy will be evicted when the lifetime ends. Mutually exclusive with the
evict
parameter. -
serializer
(SerializerT | None
, default:None
) –Optionally override the default serializer for the store instance.
-
deserializer
(DeserializerT | None
, default:None
) –Optionally override the default deserializer for the store instance.
-
populate_target
(bool | None
, default:None
) –Pass
cache_defaults=True
andtarget=obj
to theProxy
constructor. I.e., return a proxy that (1) is already resolved, (2) can be used inisinstance
checks without resolving, and (3) is hashable without resolving ifobj
is a hashable type. This isFalse
by default because the returned proxy will hold a reference toobj
which will prevent garbage collectingobj
. IfNone
, defaults to the store-wide setting. -
skip_nonproxiable
(bool
, default:False
) –Return non-proxiable types (e.g., built-in constants like
bool
orNone
) rather than raising aNonProxiableTypeError
. -
kwargs
(Any
, default:{}
) –Additional keyword arguments to pass to
Connector.put()
.
Returns:
-
Proxy[T] | NonProxiableT
–A proxy of the object unless
obj
is a non-proxiable typeskip_nonproxiable is True
in which caseobj
is returned directly.
Raises:
-
NonProxiableTypeError
–If
obj
is a non-proxiable type. This behavior can be overridden by settingskip_nonproxiable=True
. -
ValueError
–If
evict
isTrue
andlifetime
is notNone
because these parameters are mutually exclusive.
Source code in proxystore/store/base.py
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|
proxy_batch
¶
proxy_batch(
objs: Sequence[T | NonProxiableT],
*,
evict: bool = False,
lifetime: Lifetime | None = None,
serializer: SerializerT | None = None,
deserializer: DeserializerT | None = None,
populate_target: bool | None = None,
skip_nonproxiable: bool = False,
**kwargs: Any
) -> list[Proxy[T] | NonProxiableT]
Create proxies that will resolve to an object in the store.
Parameters:
-
objs
(Sequence[T | NonProxiableT]
) –The objects to place in store and return a proxies for.
-
evict
(bool
, default:False
) –If a proxy should evict its object once resolved. Mutually exclusive with the
lifetime
parameter. -
lifetime
(Lifetime | None
, default:None
) –Attach the proxies to this lifetime. The objects associated with each proxy will be evicted when the lifetime ends. Mutually exclusive with the
evict
parameter. -
serializer
(SerializerT | None
, default:None
) –Optionally override the default serializer for the store instance.
-
deserializer
(DeserializerT | None
, default:None
) –Optionally override the default deserializer for the store instance.
-
populate_target
(bool | None
, default:None
) –Pass
cache_defaults=True
andtarget=obj
to theProxy
constructor. I.e., return a proxy that (1) is already resolved, (2) can be used inisinstance
checks without resolving, and (3) is hashable without resolving ifobj
is a hashable type. IfNone
, defaults to the store-wide setting. -
skip_nonproxiable
(bool
, default:False
) –Return non-proxiable types (e.g., built-in constants like
bool
orNone
) rather than raising aNonProxiableTypeError
. -
kwargs
(Any
, default:{}
) –Additional keyword arguments to pass to
Connector.put_batch()
.
Returns:
-
list[Proxy[T] | NonProxiableT]
–A list of proxies of each object or the object itself if said object is not proxiable and
skip_nonproxiable is True
.
Raises:
-
NonProxiableTypeError
–If
obj
is a non-proxiable type. This behavior can be overridden by settingskip_nonproxiable=True
. -
ValueError
–If
evict
isTrue
andlifetime
is notNone
because these parameters are mutually exclusive.
Source code in proxystore/store/base.py
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proxy_from_key
¶
proxy_from_key(
key: ConnectorKeyT,
*,
evict: bool = False,
lifetime: Lifetime | None = None,
deserializer: DeserializerT | None = None
) -> Proxy[T]
Create a proxy that will resolve to an object already in the store.
Parameters:
-
key
(ConnectorKeyT
) –The key associated with an object already in the store.
-
evict
(bool
, default:False
) –If the proxy should evict the object once resolved. Mutually exclusive with the
lifetime
parameter. -
lifetime
(Lifetime | None
, default:None
) –Attach the proxy to this lifetime. The object associated with the proxy will be evicted when the lifetime ends. Mutually exclusive with the
evict
parameter. -
deserializer
(DeserializerT | None
, default:None
) –Optionally override the default deserializer for the store instance.
Returns:
-
Proxy[T]
–A proxy of the object.
Raises:
-
ValueError
–If
evict
isTrue
andlifetime
is notNone
because these parameters are mutually exclusive.
Source code in proxystore/store/base.py
locked_proxy
¶
locked_proxy(
obj: T | NonProxiableT,
*,
evict: bool = False,
lifetime: Lifetime | None = None,
serializer: SerializerT | None = None,
deserializer: DeserializerT | None = None,
populate_target: bool | None = None,
skip_nonproxiable: bool = True,
**kwargs: Any
) -> ProxyLocker[T] | NonProxiableT
Proxy an object and return ProxyLocker
.
Parameters:
-
obj
(T | NonProxiableT
) –The object to place in store and return a proxy for.
-
evict
(bool
, default:False
) –If the proxy should evict the object once resolved. Mutually exclusive with the
lifetime
parameter. -
lifetime
(Lifetime | None
, default:None
) –Attach the proxy to this lifetime. The object associated with the proxy will be evicted when the lifetime ends. Mutually exclusive with the
evict
parameter. -
serializer
(SerializerT | None
, default:None
) –Optionally override the default serializer for the store instance.
-
deserializer
(DeserializerT | None
, default:None
) –Optionally override the default deserializer for the store instance.
-
populate_target
(bool | None
, default:None
) –Pass
cache_defaults=True
andtarget=obj
to theProxy
constructor. I.e., return a proxy that (1) is already resolved, (2) can be used inisinstance
checks without resolving, and (3) is hashable without resolving ifobj
is a hashable type. IfNone
, defaults to the store-wide setting. -
skip_nonproxiable
(bool
, default:True
) –Return non-proxiable types (e.g., built-in constants like
bool
orNone
) rather than raising aNonProxiableTypeError
. -
kwargs
(Any
, default:{}
) –Additional keyword arguments to pass to
Connector.put()
.
Returns:
-
ProxyLocker[T] | NonProxiableT
–A proxy wrapped in a
ProxyLocker
unlessobj
is a non-proxiable typeskip_nonproxiable is True
in which caseobj
is returned directly.
Raises:
-
NonProxiableTypeError
–If
obj
is a non-proxiable type. This behavior can be overridden by settingskip_nonproxiable=True
. -
ValueError
–If
evict
isTrue
andlifetime
is notNone
because these parameters are mutually exclusive.
Source code in proxystore/store/base.py
owned_proxy
¶
owned_proxy(
obj: T | NonProxiableT,
*,
serializer: SerializerT | None = None,
deserializer: DeserializerT | None = None,
populate_target: bool | None = None,
skip_nonproxiable: bool = True,
**kwargs: Any
) -> OwnedProxy[T] | NonProxiableT
Create a proxy that will enforce ownership rules over the object.
An OwnedProxy
will auto-evict
the object once it goes out of scope. This proxy type can also
be borrowed.
Parameters:
-
obj
(T | NonProxiableT
) –The object to place in store and return a proxy for.
-
serializer
(SerializerT | None
, default:None
) –Optionally override the default serializer for the store instance.
-
deserializer
(DeserializerT | None
, default:None
) –Optionally override the default deserializer for the store instance.
-
populate_target
(bool | None
, default:None
) –Pass
cache_defaults=True
andtarget=obj
to theProxy
constructor. I.e., return a proxy that (1) is already resolved, (2) can be used inisinstance
checks without resolving, and (3) is hashable without resolving ifobj
is a hashable type. IfNone
, defaults to the store-wide setting. -
skip_nonproxiable
(bool
, default:True
) –Return non-proxiable types (e.g., built-in constants like
bool
orNone
) rather than raising aNonProxiableTypeError
. -
kwargs
(Any
, default:{}
) –Additional keyword arguments to pass to
Connector.put()
.
Returns:
-
OwnedProxy[T] | NonProxiableT
–A proxy of the object unless
obj
is a non-proxiable typeskip_nonproxiable is True
in which caseobj
is returned directly.
Raises:
-
NonProxiableTypeError
–If
obj
is a non-proxiable type. This behavior can be overridden by settingskip_nonproxiable=True
.
Source code in proxystore/store/base.py
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|
put
¶
put(
obj: Any,
*,
lifetime: Lifetime | None = None,
serializer: SerializerT | None = None,
**kwargs: Any
) -> ConnectorKeyT
Put an object in the store.
Parameters:
-
obj
(Any
) –Object to put in the store.
-
serializer
(SerializerT | None
, default:None
) –Optionally override the default serializer for the store instance.
-
lifetime
(Lifetime | None
, default:None
) –Attach the key to this lifetime. The object associated with the key will be evicted when the lifetime ends.
-
kwargs
(Any
, default:{}
) –Additional keyword arguments to pass to
Connector.put()
.
Returns:
-
ConnectorKeyT
–A key which can be used to retrieve the object.
Raises:
-
TypeError
–If the output of
serializer
is not bytes.
Source code in proxystore/store/base.py
put_batch
¶
put_batch(
objs: Sequence[Any],
*,
lifetime: Lifetime | None = None,
serializer: SerializerT | None = None,
**kwargs: Any
) -> list[ConnectorKeyT]
Put multiple objects in the store.
Parameters:
-
objs
(Sequence[Any]
) –Sequence of objects to put in the store.
-
serializer
(SerializerT | None
, default:None
) –Optionally override the default serializer for the store instance.
-
lifetime
(Lifetime | None
, default:None
) –Attach the keys to this lifetime. The objects associated with each key will be evicted when the lifetime ends.
-
kwargs
(Any
, default:{}
) –Additional keyword arguments to pass to
Connector.put_batch()
.
Returns:
-
list[ConnectorKeyT]
–A list of keys which can be used to retrieve the objects.
Raises:
-
TypeError
–If the output of
serializer
is not bytes.
Source code in proxystore/store/base.py
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StoreConfig
¶
Bases: BaseModel
Store configuration.
Tip
See the Store
parameters for more
information about each configuration option.
Attributes:
-
name
(str
) –Store name.
-
connector
(ConnectorConfig
) –Connector configuration.
-
serializer
(Optional[SerializerT]
) –Optional serializer.
-
deserializer
(Optional[DeserializerT]
) –Optional deserializer.
-
cache_size
(int
) –Cache size.
-
metrics
(bool
) –Enable recording operation metrics.
-
populate_target
(bool
) –Set the default value for the
populate_target
parameter of proxy methods. -
auto_register
(bool
) –Auto-register the store.
from_toml
classmethod
¶
Create a configuration file from a TOML file.
Example
See
write_toml()
.
Parameters:
Source code in proxystore/store/config.py
write_toml
¶
Write a configuration to a TOML file.
Example
from proxystore.store.config import ConnectorConfig
from proxystore.store.config import StoreConfig
config = StoreConfig(
name='example',
connector=ConnectorConfig(
kind='file',
options={'store_dir': '/tmp/proxystore-cache'},
),
)
config.write_toml('config.toml')
StoreConfig.from_toml('config.toml')
.
Parameters:
Source code in proxystore/store/config.py
StoreFactory
¶
StoreFactory(
key: ConnectorKeyT,
store_config: StoreConfig,
*,
evict: bool = False,
deserializer: DeserializerT | None = None
)
Bases: Generic[ConnectorT, T]
Factory that resolves an object from a store.
Adds support for asynchronously retrieving objects from a
Store
instance.
The factory takes the store_config
parameter that is
used to reinitialize the store if the factory is sent to a remote
process where the store has not already been initialized.
Parameters:
-
key
(ConnectorKeyT
) –Key corresponding to object in store.
-
store_config
(StoreConfig
) –Store configuration used to reinitialize the store if needed.
-
evict
(bool
, default:False
) –If True, evict the object from the store once
resolve()
is called. -
deserializer
(DeserializerT | None
, default:None
) –Optional callable used to deserialize the byte string. If
None
, the default deserializer (deserialize()
) will be used.
Source code in proxystore/store/factory.py
get_store
¶
get_store() -> Store[ConnectorT]
resolve
¶
Get object associated with key from store.
Raises:
-
ProxyResolveMissingKeyError
–If the key associated with this factory does not exist in the store.
Source code in proxystore/store/factory.py
resolve_async
¶
Asynchronously get object associated with key from store.
get_store
¶
Get a registered store by name.
Parameters:
Returns:
-
Store[Any] | None
–Store
if a store matching the name or belonging to the proxy exists. If the store does not exist, returnsNone
.
Raises:
-
ProxyStoreFactoryError
–If the value is a proxy but does not contain a factory of type
StoreFactory
.
Source code in proxystore/store/__init__.py
get_or_create_store
¶
get_or_create_store(
store_config: StoreConfig, *, register: bool = True
) -> Store[Any]
Get a registered store or initialize a new instance from the config.
Parameters:
-
store_config
(StoreConfig
) –Store configuration used to reinitialize the store if needed.
-
register
(bool
, default:True
) –Optionally register the store if a new instance was initialized.
Returns:
Source code in proxystore/store/__init__.py
register_store
¶
Register the store instance to the global registry.
Note
Global means globally accessible within the Python process.
Tip
Use the store_registration
context manager to automatically register and unregister as store.
Parameters:
-
store
(Store[Any]
) –Store instance to register.
-
exist_ok
(bool
, default:False
) –If a store with the same name exists, overwrite it.
Raises:
-
StoreExistsError
–If a store with the same name is already registered and
exist_ok
is false.
Source code in proxystore/store/__init__.py
store_registration
¶
Context manager that registers and unregisters a set of stores.
Example
from proxystore.connectors.local import LocalConnector
from proxystore.store import Store
from proxystore.store import store_registration
with Store('store', LocalConnector()) as store:
with store_registration(store):
...
stores = [
Store('store1', LocalConnector()),
Store('store2', LocalConnector()),
]
with store_registration(*stores):
...
Parameters:
-
stores
(Store[Any]
, default:()
) –Set of
Store
instances to register then unregister when the context manager is exited. -
exist_ok
(bool
, default:False
) –If a store with the same name exists, overwrite it.
Raises:
-
StoreExistsError
–If a store with the same name is already registered and
exist_ok
is false.
Source code in proxystore/store/__init__.py
unregister_store
¶
Unregisters the store instance from the global registry.
Note
This function is a no-op if no store matching the name exists (i.e., no exception will be raised).
Parameters: