yr.InstanceCreator.snapstart

InstanceCreator.snapstart(checkpoint_id: str) → InstanceProxy

Start a new instance from a checkpoint snapshot.

This class method creates a new instance by restoring from a previously created snapshot. The new instance will have the same state as when the snapshot was taken.

Parameters:

checkpoint_id (str) – The checkpoint ID returned by a previous snapshot() call. Format: {instanceID}-{functionID}-{uuid}

Returns:

A new instance proxy for the restored instance.

Return type:

InstanceProxy

Raises:

RuntimeError – If the checkpoint does not exist or restore operation fails.

Example

>>> import yr
>>> yr.init()
>>>
>>> @yr.instance
... class Counter:
...     def __init__(self):
...         self.value = 0
...
...     def increment(self):
...         self.value += 1
...         return self.value
...
...     def __yr_after_snapstart__(self):
...         print(f"Restored with value={self.value}")
...
>>> # Create instance and snapshot
>>> ins = Counter.invoke()
>>> yr.get(ins.increment.invoke())  # value = 1
>>> checkpoint_id = ins.snapshot(leave_running=False)
>>>
>>> # Restore from snapshot using the class
>>> restored_ins = Counter.snapstart(checkpoint_id)
>>> result = yr.get(restored_ins.increment.invoke())  # value = 2
>>> print(f"Value after restore: {result}")
>>>
>>> yr.finalize()