teos.builder

class Builder

Bases: object

The Builder class is in charge of reconstructing data loaded from the appointments database and build the data structures of the Watcher and the Responder.

static build_appointments(appointments_data)

Builds an appointments dictionary (uuid:extended_appointment) and a locator_uuid_map (locator:uuid) given a dictionary of appointments from the database.

Parameters

appointments_data (dict) –

a dictionary of dictionaries representing all the Watcher appointments stored in the database. The structure is as follows:

{uuid: {locator: str, ...}, uuid: {locator:...}}

Returns

A tuple with two dictionaries. appointments containing the appointment information in ExtendedAppointment objects and locator_uuid_map containing a map of appointment (uuid:locator).

Return type

tuple

static build_trackers(tracker_data)

Builds a tracker dictionary (uuid:TransactionTracker) and a tx_tracker_map (penalty_txid:uuid) given a dictionary of trackers from the database.

Parameters

tracker_data (dict) –

a dictionary of dictionaries representing all the Responder trackers stored in the database. The structure is as follows:

{uuid: {locator: str, dispute_txid: str, ...}, uuid: {locator:...}}

Returns

A tuple with two dictionaries. trackers containing the trackers’ information in TransactionTracker objects and a tx_tracker_map containing the map of trackers (penalty_txid: uuid).

Return type

tuple

static populate_block_queue(block_queue, missed_blocks)

Populates a Queue of block hashes to initialize the Watcher or the Responder using backed up data.

Parameters

• block_queue (Queue) – a queue.

• missed_blocks (list) – list of block hashes missed by the Watchtower (due to a crash or shutdown).

Returns

A queue containing all the missed blocks hashes.

Return type

Queue

static update_states(watcher, missed_blocks_watcher, missed_blocks_responder)

Updates the states of both the Watcher and the Responder. If both have pending blocks to process they need to be updated at the same time, block by block.

If only one instance has to be updated, populate_block_queue should be used.

Parameters

• watcher (Watcher) – a Watcher instance (including a Responder).

• missed_blocks_watcher (list) – the list of block missed by the Watcher.

• missed_blocks_responder (list) – the list of block missed by the Responder.

Raises

ValueError – if one of the provided list is empty.