def __init__(self, w3: Web3) -> None:
self.w3 = w3
self.table_key = f"chain{CONFIG.active_network['chainid']}"
self.cur = Cursor(_get_data_folder().joinpath("cache.db"))
self.cur.execute(f"CREATE TABLE IF NOT EXISTS {self.table_key} (method, params, result)")
latest = w3.eth.getBlock("latest")
self.last_block = latest.hash
self.last_block_seen = latest.timestamp
self.last_request = 0.0
self.block_cache: OrderedDict = OrderedDict()
self.block_filter = w3.eth.filter("latest")
self.lock = threading.Lock()
self.event = threading.Event()
self.is_killed = False
threading.Thread(target=self.block_filter_loop, daemon=True).start()
from hashlib import sha1
from sqlite3 import OperationalError
from typing import Any, Dict, Iterator, List, Optional, Tuple
from brownie._config import CONFIG, _get_data_folder
from brownie._singleton import _Singleton
from brownie.exceptions import BrownieEnvironmentError
from brownie.project.build import DEPLOYMENT_KEYS
from brownie.utils.sql import Cursor
from .rpc import _revert_register
from .web3 import _resolve_address
_contract_map: Dict = {}
cur = Cursor(_get_data_folder().joinpath(f"deployments.db"))
cur.execute("CREATE TABLE IF NOT EXISTS sources (hash PRIMARY KEY, source)")
class TxHistory(metaclass=_Singleton):
"""List-like singleton container that contains TransactionReceipt objects.
Whenever a transaction is broadcast, the TransactionReceipt is automatically
added to this container."""
def __init__(self) -> None:
self._list: List = []
self.gas_profile: Dict = {}
_revert_register(self)
def __repr__(self) -> str:
class RequestCachingMiddleware(BrownieMiddlewareABC):
"""
Web3 middleware for request caching.
"""
def __init__(self, w3: Web3) -> None:
self.w3 = w3
self.table_key = f"chain{CONFIG.active_network['chainid']}"
self.cur = Cursor(_get_data_folder().joinpath("cache.db"))
self.cur.execute(
f"CREATE TABLE IF NOT EXISTS {self.table_key} (method, params, result)"
)
latest = w3.eth.getBlock("latest")
self.last_block = latest.hash
self.last_block_seen = latest.timestamp
self.last_request = 0.0
self.block_cache: OrderedDict = OrderedDict()
self.block_filter = w3.eth.filter("latest")
self.lock = threading.Lock()
self.event = threading.Event()
self.is_killed = False
threading.Thread(target=self.block_filter_loop, daemon=True).start()
@classmethod
def get_layer(cls, w3: Web3, network_type: str) -> Optional[int]:
if network_type == "live":
return 0
else:
return None
@property
def time_since(self) -> float:
return time.time() - self.last_request
def block_filter_loop(self) -> None:
while not self.is_killed:
# if the last RPC request was > 60 seconds ago, reduce the rate of updates.
# we eventually settle at one query per minute after 10 minutes of no requests.
with self.lock:
if self.time_since > 60:
self.block_cache.clear()
self.event.clear()
if self.time_since > 60:
self.event.wait(min(self.time_since / 10, 60))
# query the filter for new blocks
with self.lock:
try:
new_blocks = self.block_filter.get_new_entries()
except (AttributeError, ValueError):
# web3 has disconnected, or the filter has expired from inactivity
if self.w3.isConnected():
self.block_filter = self.w3.eth.filter("latest")
continue
else:
return
if new_blocks:
self.block_cache[new_blocks[-1]] = {}
self.last_block = new_blocks[-1]
self.last_block_seen = time.time()
if len(self.block_cache) > 5:
old_key = list(self.block_cache)[0]
del self.block_cache[old_key]
if new_blocks and self.time_since < 15:
# if this update found a new block and we've been querying
# frequently, we can wait a few seconds before the next update
time.sleep(5)
elif time.time() - self.last_block_seen < 15:
# if it's been less than 15 seconds since the last block, wait 2 seconds
time.sleep(2)
else:
# if it's been more than 15 seconds, only wait 1 second
time.sleep(1)
def process_request(self, make_request: Callable, method: str,
params: List) -> Dict:
# do not apply this middleware to filter updates or we'll die recursion death
# clientVersion is used to check connectivity so we also don't cache that
if method in ("eth_getFilterChanges", "eth_uninstallFilter",
"web3_clientVersion"):
return make_request(method, params)
# try to return a cached value
param_str = json.dumps(params, separators=(",", ""), default=str)
# check if the value is available within the long-term cache
if method in LONGTERM_CACHE:
row = self.cur.fetchone(
f"SELECT result FROM {self.table_key} WHERE method=? AND params=?",
(method, param_str),
)
if row:
data = row[0]
if isinstance(data, bytes):
data = HexBytes(data)
return {"id": "cache", "jsonrpc": "2.0", "result": data}
with self.lock:
self.last_request = time.time()
self.event.set()
try:
return self.block_cache[self.last_block][method][param_str]
except KeyError:
pass
# cached value is unavailable, make a request and cache the result
with self.lock:
response = make_request(method, params)
self.block_cache.setdefault(self.last_block,
{}).setdefault(method, {})
self.block_cache[self.last_block][method][param_str] = response
# check if the value can be added to long-term cache
if "result" in response and method in LONGTERM_CACHE:
result = response["result"]
if LONGTERM_CACHE[method](self.w3, result):
if isinstance(result, (dict, list, tuple)):
result = json.dumps(response,
separators=(",", ""),
default=str)
self.cur.insert(self.table_key, method, param_str, result)
return response
def uninstall(self) -> None:
self.is_killed = True
if self.w3.isConnected():
self.w3.eth.uninstallFilter(self.block_filter.filter_id)
