import asyncio
from aiozk import exc, WatchEvent, Deadline
from .recipe import Recipe
class Barrier(Recipe):
def __init__(self, path):
super().__init__()
self.path = path
async def create(self):
await self.ensure_path()
await self.create_znode(self.path)
async def lift(self):
try:
await self.client.delete(self.path)
except exc.NoNode:
pass
async def wait(self, timeout=None):
deadline = Deadline(timeout)
barrier_lifted = self.client.wait_for_events(
[WatchEvent.DELETED], self.path
)
exists = await self.client.exists(path=self.path, watch=True)
if not exists:
return
try:
if not deadline.is_indefinite:
await asyncio.wait_for(barrier_lifted, deadline.timeout)
else:
await barrier_lifted
except asyncio.TimeoutError:
raise exc.TimeoutError
