cic-internal-integration/apps/cic-eth/cic_eth/sync/head.py

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2021-02-01 18:12:51 +01:00
# standard imports
import logging
# third-party imports
import web3
# local imports
from .mined import MinedSyncer
from .base import Syncer
logg = logging.getLogger()
class HeadSyncer(MinedSyncer):
"""Implements the get method in Syncer for retrieving every new mined block.
:param bc_cache: Retrieves block cache cursors for chain head and latest processed block.
:type bc_cache: Object implementing methods from cic_eth.sync.SyncerBackend
"""
def __init__(self, bc_cache):
super(HeadSyncer, self).__init__(bc_cache)
# TODO: filter not returning all blocks, at least with ganache. kind of defeats the point, then
#self.w3_filter = rpc.w3.eth.filter({
# 'fromBlock': block_offset,
# }) #'latest')
#self.bc_cache.set(block_offset, 0)
logg.debug('initialized head syncer with offset {}'.format(bc_cache.start()))
"""Implements Syncer.get
:param w3: Web3 object
:type w3: web3.Web3
:returns: Block hash of newly mined blocks. if any
:rtype: list of str, 0x-hex
"""
def get(self, w3):
# Of course, the filter doesn't return the same block dict format as getBlock() so we'll just waste some cycles getting the hashes instead.
#hashes = []
#for block in self.w3_filter.get_new_entries():
# hashes.append(block['blockHash'])
#logg.debug('blocks {}'.format(hashes))
#return hashes
(block_number, tx_number) = self.bc_cache.get()
block_hash = []
try:
block = w3.eth.getBlock(block_number)
block_hash.append(block.hash)
except web3.exceptions.BlockNotFound:
pass
return block_hash