zulip/zerver/lib/utils.py

110 lines
3.0 KiB
Python

import hashlib
import re
import secrets
from typing import Any, Callable, List, Optional, TypeVar
from django.conf import settings
T = TypeVar("T")
def statsd_key(val: str, clean_periods: bool = False) -> str:
if ":" in val:
val = val.split(":")[0]
val = val.replace("-", "_")
if clean_periods:
val = val.replace(".", "_")
return val
class StatsDWrapper:
"""Transparently either submit metrics to statsd
or do nothing without erroring out"""
# Backported support for gauge deltas
# as our statsd server supports them but supporting
# pystatsd is not released yet
def _our_gauge(self, stat: str, value: float, rate: float = 1, delta: bool = False) -> None:
"""Set a gauge value."""
from django_statsd.clients import statsd
if delta:
value_str = f"{value:+g}|g"
else:
value_str = f"{value:g}|g"
statsd._send(stat, value_str, rate)
def __getattr__(self, name: str) -> Any:
# Hand off to statsd if we have it enabled
# otherwise do nothing
if name in ["timer", "timing", "incr", "decr", "gauge"]:
if settings.STATSD_HOST != "":
from django_statsd.clients import statsd
if name == "gauge":
return self._our_gauge
else:
return getattr(statsd, name)
else:
return lambda *args, **kwargs: None
raise AttributeError
statsd = StatsDWrapper()
def make_safe_digest(string: str, hash_func: Callable[[bytes], Any] = hashlib.sha1) -> str:
"""
return a hex digest of `string`.
"""
# hashlib.sha1, md5, etc. expect bytes, so non-ASCII strings must
# be encoded.
return hash_func(string.encode()).hexdigest()
def log_statsd_event(name: str) -> None:
"""
Sends a single event to statsd with the desired name and the current timestamp
This can be used to provide vertical lines in generated graphs,
for example when doing a prod deploy, bankruptcy request, or
other one-off events
Note that to draw this event as a vertical line in graphite
you can use the drawAsInfinite() command
"""
event_name = f"events.{name}"
statsd.incr(event_name)
def generate_api_key() -> str:
api_key = ""
while len(api_key) < 32:
# One iteration suffices 99.4992% of the time.
api_key += secrets.token_urlsafe(3 * 9).replace("_", "").replace("-", "")
return api_key[:32]
def has_api_key_format(key: str) -> bool:
return bool(re.fullmatch(r"([A-Za-z0-9]){32}", key))
def assert_is_not_none(value: Optional[T]) -> T:
assert value is not None
return value
def process_list_in_batches(
lst: List[T], chunk_size: int, process_batch: Callable[[List[T]], None]
) -> None:
offset = 0
while True:
items = lst[offset : offset + chunk_size]
if not items:
break
process_batch(items)
offset += chunk_size