Shared state

The momotor.rpc.shared module contains wrapper classes to use the shared state services

class momotor.rpc.shared.SharedState(stub)

An implementation of momotor.shared.state.StateABC for use by workers.

Produces log messages on the momotor.rpc.shared logger.

Parameters

stub (WorkerStub) – The connected worker stub

get_lock(key, *, exclusive=True)

Context manager to get a lock. The lock is held while the context is active.

The lock is an ‘exclusive’ or ‘read/write’ lock:

• Many processes can hold the lock with exclusive==False (read mode), but

• Only one process can hold the lock with exclusive==True (write mode). No other processes can hold the lock while one process has it locked exclusively.

Parameters

• key (str) – global name for the lock

• exclusive (bool) – get an exclusive lock

Return type

AbstractAsyncContextManager[None]

Returns

Raises

LockFailed

async test_lock(key, *, exclusive=True)

Test the lock. Returns True if the lock is currently not being held.

Not that this is very transient information. The lock could be acquired immediately after this method returns.

Parameters

• key (str) – global name for the lock

• exclusive (bool) – get an exclusive lock

Return type

bool

Returns