blob: a0dc0c170f2b469258b40e44db0ec2dcc6bae960 [file] [log] [blame]
# Copyright (C) 2019 Garmin Ltd.
#
# SPDX-License-Identifier: GPL-2.0-only
#
from contextlib import closing, contextmanager
from datetime import datetime
import asyncio
import json
import logging
import math
import os
import signal
import socket
import sys
import time
from . import chunkify, DEFAULT_MAX_CHUNK, create_async_client, TABLE_COLUMNS
logger = logging.getLogger('hashserv.server')
class Measurement(object):
def __init__(self, sample):
self.sample = sample
def start(self):
self.start_time = time.perf_counter()
def end(self):
self.sample.add(time.perf_counter() - self.start_time)
def __enter__(self):
self.start()
return self
def __exit__(self, *args, **kwargs):
self.end()
class Sample(object):
def __init__(self, stats):
self.stats = stats
self.num_samples = 0
self.elapsed = 0
def measure(self):
return Measurement(self)
def __enter__(self):
return self
def __exit__(self, *args, **kwargs):
self.end()
def add(self, elapsed):
self.num_samples += 1
self.elapsed += elapsed
def end(self):
if self.num_samples:
self.stats.add(self.elapsed)
self.num_samples = 0
self.elapsed = 0
class Stats(object):
def __init__(self):
self.reset()
def reset(self):
self.num = 0
self.total_time = 0
self.max_time = 0
self.m = 0
self.s = 0
self.current_elapsed = None
def add(self, elapsed):
self.num += 1
if self.num == 1:
self.m = elapsed
self.s = 0
else:
last_m = self.m
self.m = last_m + (elapsed - last_m) / self.num
self.s = self.s + (elapsed - last_m) * (elapsed - self.m)
self.total_time += elapsed
if self.max_time < elapsed:
self.max_time = elapsed
def start_sample(self):
return Sample(self)
@property
def average(self):
if self.num == 0:
return 0
return self.total_time / self.num
@property
def stdev(self):
if self.num <= 1:
return 0
return math.sqrt(self.s / (self.num - 1))
def todict(self):
return {k: getattr(self, k) for k in ('num', 'total_time', 'max_time', 'average', 'stdev')}
class ClientError(Exception):
pass
class ServerError(Exception):
pass
def insert_task(cursor, data, ignore=False):
keys = sorted(data.keys())
query = '''INSERT%s INTO tasks_v2 (%s) VALUES (%s)''' % (
" OR IGNORE" if ignore else "",
', '.join(keys),
', '.join(':' + k for k in keys))
cursor.execute(query, data)
async def copy_from_upstream(client, db, method, taskhash):
d = await client.get_taskhash(method, taskhash, True)
if d is not None:
# Filter out unknown columns
d = {k: v for k, v in d.items() if k in TABLE_COLUMNS}
keys = sorted(d.keys())
with closing(db.cursor()) as cursor:
insert_task(cursor, d)
db.commit()
return d
async def copy_outhash_from_upstream(client, db, method, outhash, taskhash):
d = await client.get_outhash(method, outhash, taskhash)
if d is not None:
# Filter out unknown columns
d = {k: v for k, v in d.items() if k in TABLE_COLUMNS}
keys = sorted(d.keys())
with closing(db.cursor()) as cursor:
insert_task(cursor, d)
db.commit()
return d
class ServerClient(object):
FAST_QUERY = 'SELECT taskhash, method, unihash FROM tasks_v2 WHERE method=:method AND taskhash=:taskhash ORDER BY created ASC LIMIT 1'
ALL_QUERY = 'SELECT * FROM tasks_v2 WHERE method=:method AND taskhash=:taskhash ORDER BY created ASC LIMIT 1'
OUTHASH_QUERY = '''
-- Find tasks with a matching outhash (that is, tasks that
-- are equivalent)
SELECT * FROM tasks_v2 WHERE method=:method AND outhash=:outhash
-- If there is an exact match on the taskhash, return it.
-- Otherwise return the oldest matching outhash of any
-- taskhash
ORDER BY CASE WHEN taskhash=:taskhash THEN 1 ELSE 2 END,
created ASC
-- Only return one row
LIMIT 1
'''
def __init__(self, reader, writer, db, request_stats, backfill_queue, upstream, read_only):
self.reader = reader
self.writer = writer
self.db = db
self.request_stats = request_stats
self.max_chunk = DEFAULT_MAX_CHUNK
self.backfill_queue = backfill_queue
self.upstream = upstream
self.handlers = {
'get': self.handle_get,
'get-outhash': self.handle_get_outhash,
'get-stream': self.handle_get_stream,
'get-stats': self.handle_get_stats,
'chunk-stream': self.handle_chunk,
}
if not read_only:
self.handlers.update({
'report': self.handle_report,
'report-equiv': self.handle_equivreport,
'reset-stats': self.handle_reset_stats,
'backfill-wait': self.handle_backfill_wait,
})
async def process_requests(self):
if self.upstream is not None:
self.upstream_client = await create_async_client(self.upstream)
else:
self.upstream_client = None
try:
self.addr = self.writer.get_extra_info('peername')
logger.debug('Client %r connected' % (self.addr,))
# Read protocol and version
protocol = await self.reader.readline()
if protocol is None:
return
(proto_name, proto_version) = protocol.decode('utf-8').rstrip().split()
if proto_name != 'OEHASHEQUIV':
return
proto_version = tuple(int(v) for v in proto_version.split('.'))
if proto_version < (1, 0) or proto_version > (1, 1):
return
# Read headers. Currently, no headers are implemented, so look for
# an empty line to signal the end of the headers
while True:
line = await self.reader.readline()
if line is None:
return
line = line.decode('utf-8').rstrip()
if not line:
break
# Handle messages
while True:
d = await self.read_message()
if d is None:
break
await self.dispatch_message(d)
await self.writer.drain()
except ClientError as e:
logger.error(str(e))
finally:
if self.upstream_client is not None:
await self.upstream_client.close()
self.writer.close()
async def dispatch_message(self, msg):
for k in self.handlers.keys():
if k in msg:
logger.debug('Handling %s' % k)
if 'stream' in k:
await self.handlers[k](msg[k])
else:
with self.request_stats.start_sample() as self.request_sample, \
self.request_sample.measure():
await self.handlers[k](msg[k])
return
raise ClientError("Unrecognized command %r" % msg)
def write_message(self, msg):
for c in chunkify(json.dumps(msg), self.max_chunk):
self.writer.write(c.encode('utf-8'))
async def read_message(self):
l = await self.reader.readline()
if not l:
return None
try:
message = l.decode('utf-8')
if not message.endswith('\n'):
return None
return json.loads(message)
except (json.JSONDecodeError, UnicodeDecodeError) as e:
logger.error('Bad message from client: %r' % message)
raise e
async def handle_chunk(self, request):
lines = []
try:
while True:
l = await self.reader.readline()
l = l.rstrip(b"\n").decode("utf-8")
if not l:
break
lines.append(l)
msg = json.loads(''.join(lines))
except (json.JSONDecodeError, UnicodeDecodeError) as e:
logger.error('Bad message from client: %r' % message)
raise e
if 'chunk-stream' in msg:
raise ClientError("Nested chunks are not allowed")
await self.dispatch_message(msg)
async def handle_get(self, request):
method = request['method']
taskhash = request['taskhash']
if request.get('all', False):
row = self.query_equivalent(method, taskhash, self.ALL_QUERY)
else:
row = self.query_equivalent(method, taskhash, self.FAST_QUERY)
if row is not None:
logger.debug('Found equivalent task %s -> %s', (row['taskhash'], row['unihash']))
d = {k: row[k] for k in row.keys()}
elif self.upstream_client is not None:
d = await copy_from_upstream(self.upstream_client, self.db, method, taskhash)
else:
d = None
self.write_message(d)
async def handle_get_outhash(self, request):
with closing(self.db.cursor()) as cursor:
cursor.execute(self.OUTHASH_QUERY,
{k: request[k] for k in ('method', 'outhash', 'taskhash')})
row = cursor.fetchone()
if row is not None:
logger.debug('Found equivalent outhash %s -> %s', (row['outhash'], row['unihash']))
d = {k: row[k] for k in row.keys()}
else:
d = None
self.write_message(d)
async def handle_get_stream(self, request):
self.write_message('ok')
while True:
upstream = None
l = await self.reader.readline()
if not l:
return
try:
# This inner loop is very sensitive and must be as fast as
# possible (which is why the request sample is handled manually
# instead of using 'with', and also why logging statements are
# commented out.
self.request_sample = self.request_stats.start_sample()
request_measure = self.request_sample.measure()
request_measure.start()
l = l.decode('utf-8').rstrip()
if l == 'END':
self.writer.write('ok\n'.encode('utf-8'))
return
(method, taskhash) = l.split()
#logger.debug('Looking up %s %s' % (method, taskhash))
row = self.query_equivalent(method, taskhash, self.FAST_QUERY)
if row is not None:
msg = ('%s\n' % row['unihash']).encode('utf-8')
#logger.debug('Found equivalent task %s -> %s', (row['taskhash'], row['unihash']))
elif self.upstream_client is not None:
upstream = await self.upstream_client.get_unihash(method, taskhash)
if upstream:
msg = ("%s\n" % upstream).encode("utf-8")
else:
msg = "\n".encode("utf-8")
else:
msg = '\n'.encode('utf-8')
self.writer.write(msg)
finally:
request_measure.end()
self.request_sample.end()
await self.writer.drain()
# Post to the backfill queue after writing the result to minimize
# the turn around time on a request
if upstream is not None:
await self.backfill_queue.put((method, taskhash))
async def handle_report(self, data):
with closing(self.db.cursor()) as cursor:
cursor.execute(self.OUTHASH_QUERY,
{k: data[k] for k in ('method', 'outhash', 'taskhash')})
row = cursor.fetchone()
if row is None and self.upstream_client:
# Try upstream
row = await copy_outhash_from_upstream(self.upstream_client,
self.db,
data['method'],
data['outhash'],
data['taskhash'])
# If no matching outhash was found, or one *was* found but it
# wasn't an exact match on the taskhash, a new entry for this
# taskhash should be added
if row is None or row['taskhash'] != data['taskhash']:
# If a row matching the outhash was found, the unihash for
# the new taskhash should be the same as that one.
# Otherwise the caller provided unihash is used.
unihash = data['unihash']
if row is not None:
unihash = row['unihash']
insert_data = {
'method': data['method'],
'outhash': data['outhash'],
'taskhash': data['taskhash'],
'unihash': unihash,
'created': datetime.now()
}
for k in ('owner', 'PN', 'PV', 'PR', 'task', 'outhash_siginfo'):
if k in data:
insert_data[k] = data[k]
insert_task(cursor, insert_data)
self.db.commit()
logger.info('Adding taskhash %s with unihash %s',
data['taskhash'], unihash)
d = {
'taskhash': data['taskhash'],
'method': data['method'],
'unihash': unihash
}
else:
d = {k: row[k] for k in ('taskhash', 'method', 'unihash')}
self.write_message(d)
async def handle_equivreport(self, data):
with closing(self.db.cursor()) as cursor:
insert_data = {
'method': data['method'],
'outhash': "",
'taskhash': data['taskhash'],
'unihash': data['unihash'],
'created': datetime.now()
}
for k in ('owner', 'PN', 'PV', 'PR', 'task', 'outhash_siginfo'):
if k in data:
insert_data[k] = data[k]
insert_task(cursor, insert_data, ignore=True)
self.db.commit()
# Fetch the unihash that will be reported for the taskhash. If the
# unihash matches, it means this row was inserted (or the mapping
# was already valid)
row = self.query_equivalent(data['method'], data['taskhash'], self.FAST_QUERY)
if row['unihash'] == data['unihash']:
logger.info('Adding taskhash equivalence for %s with unihash %s',
data['taskhash'], row['unihash'])
d = {k: row[k] for k in ('taskhash', 'method', 'unihash')}
self.write_message(d)
async def handle_get_stats(self, request):
d = {
'requests': self.request_stats.todict(),
}
self.write_message(d)
async def handle_reset_stats(self, request):
d = {
'requests': self.request_stats.todict(),
}
self.request_stats.reset()
self.write_message(d)
async def handle_backfill_wait(self, request):
d = {
'tasks': self.backfill_queue.qsize(),
}
await self.backfill_queue.join()
self.write_message(d)
def query_equivalent(self, method, taskhash, query):
# This is part of the inner loop and must be as fast as possible
try:
cursor = self.db.cursor()
cursor.execute(query, {'method': method, 'taskhash': taskhash})
return cursor.fetchone()
except:
cursor.close()
class Server(object):
def __init__(self, db, loop=None, upstream=None, read_only=False):
if upstream and read_only:
raise ServerError("Read-only hashserv cannot pull from an upstream server")
self.request_stats = Stats()
self.db = db
if loop is None:
self.loop = asyncio.new_event_loop()
self.close_loop = True
else:
self.loop = loop
self.close_loop = False
self.upstream = upstream
self.read_only = read_only
self._cleanup_socket = None
def start_tcp_server(self, host, port):
self.server = self.loop.run_until_complete(
asyncio.start_server(self.handle_client, host, port, loop=self.loop)
)
for s in self.server.sockets:
logger.info('Listening on %r' % (s.getsockname(),))
# Newer python does this automatically. Do it manually here for
# maximum compatibility
s.setsockopt(socket.SOL_TCP, socket.TCP_NODELAY, 1)
s.setsockopt(socket.SOL_TCP, socket.TCP_QUICKACK, 1)
name = self.server.sockets[0].getsockname()
if self.server.sockets[0].family == socket.AF_INET6:
self.address = "[%s]:%d" % (name[0], name[1])
else:
self.address = "%s:%d" % (name[0], name[1])
def start_unix_server(self, path):
def cleanup():
os.unlink(path)
cwd = os.getcwd()
try:
# Work around path length limits in AF_UNIX
os.chdir(os.path.dirname(path))
self.server = self.loop.run_until_complete(
asyncio.start_unix_server(self.handle_client, os.path.basename(path), loop=self.loop)
)
finally:
os.chdir(cwd)
logger.info('Listening on %r' % path)
self._cleanup_socket = cleanup
self.address = "unix://%s" % os.path.abspath(path)
async def handle_client(self, reader, writer):
# writer.transport.set_write_buffer_limits(0)
try:
client = ServerClient(reader, writer, self.db, self.request_stats, self.backfill_queue, self.upstream, self.read_only)
await client.process_requests()
except Exception as e:
import traceback
logger.error('Error from client: %s' % str(e), exc_info=True)
traceback.print_exc()
writer.close()
logger.info('Client disconnected')
@contextmanager
def _backfill_worker(self):
async def backfill_worker_task():
client = await create_async_client(self.upstream)
try:
while True:
item = await self.backfill_queue.get()
if item is None:
self.backfill_queue.task_done()
break
method, taskhash = item
await copy_from_upstream(client, self.db, method, taskhash)
self.backfill_queue.task_done()
finally:
await client.close()
async def join_worker(worker):
await self.backfill_queue.put(None)
await worker
if self.upstream is not None:
worker = asyncio.ensure_future(backfill_worker_task())
try:
yield
finally:
self.loop.run_until_complete(join_worker(worker))
else:
yield
def serve_forever(self):
def signal_handler():
self.loop.stop()
asyncio.set_event_loop(self.loop)
try:
self.backfill_queue = asyncio.Queue()
self.loop.add_signal_handler(signal.SIGTERM, signal_handler)
with self._backfill_worker():
try:
self.loop.run_forever()
except KeyboardInterrupt:
pass
self.server.close()
self.loop.run_until_complete(self.server.wait_closed())
logger.info('Server shutting down')
finally:
if self.close_loop:
if sys.version_info >= (3, 6):
self.loop.run_until_complete(self.loop.shutdown_asyncgens())
self.loop.close()
if self._cleanup_socket is not None:
self._cleanup_socket()