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TransactionSubscriptionProtocol

TransactionSubscriptionProtocol Objects​

class TransactionSubscriptionProtocol(typing.Protocol)

A live subscription.

Call next in a loop to receive updates; it only returns None once cancel has been called, since the subscription itself never ends.

cancel​

def cancel() -> None

Cancel the subscription, dropping the connection and unblocking a pending next.

Idempotent, and safe to call while next is pending — the pending call drops the connection on its way out.

Named cancel rather than close because a close method collides with the disposal method uniffi generates for objects in some languages.

is_canceled​

def is_canceled() -> bool

Whether the subscription has been canceled.

next​

async def next() -> typing.Optional[TransactionUpdate]

Wait for the next update.

Returns None once the subscription has been canceled. Concurrent calls are serialized; there is no ordering guarantee between them.

Raises for errors the subscription cannot recover from by itself, such as a rejected filter. The subscription stays usable afterwards, so a caller that considers the error transient can keep calling next.