def wrapped(*args, **kwargs):
arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs)
keyargs = [arg_dict[arg_nm] for arg_nm in self.arg_names]
list_args = arg_dict[self.list_name]
# cached is a dict arg -> deferred, where deferred results in a
# 2-tuple (`arg`, `result`)
cached = {}
missing = []
for arg in list_args:
key = list(keyargs)
key[self.list_pos] = arg
try:
res = self.cache.get(tuple(key)).observe()
res.addCallback(lambda r, arg: (arg, r), arg)
cached[arg] = res
except KeyError:
missing.append(arg)
if missing:
sequence = self.cache.sequence
args_to_call = dict(arg_dict)
args_to_call[self.list_name] = missing
ret_d = defer.maybeDeferred(
preserve_context_over_fn,
self.function_to_call,
**args_to_call
)
ret_d = ObservableDeferred(ret_d)
# We need to create deferreds for each arg in the list so that
# we can insert the new deferred into the cache.
for arg in missing:
with PreserveLoggingContext():
observer = ret_d.observe()
observer.addCallback(lambda r, arg: r.get(arg, None), arg)
observer = ObservableDeferred(observer)
key = list(keyargs)
key[self.list_pos] = arg
self.cache.update(sequence, tuple(key), observer)
def invalidate(f, key):
self.cache.invalidate(key)
return f
observer.addErrback(invalidate, tuple(key))
res = observer.observe()
res.addCallback(lambda r, arg: (arg, r), arg)
cached[arg] = res
return preserve_context_over_deferred(defer.gatherResults(
cached.values(),
consumeErrors=True,
).addErrback(unwrapFirstError).addCallback(lambda res: dict(res)))
def wait_for_previous_lookups(self, server_names, server_to_deferred):
"""Waits for any previous key lookups for the given servers to finish.
Args:
server_names (list): list of server_names we want to lookup
server_to_deferred (dict): server_name to deferred which gets
resolved once we've finished looking up keys for that server
"""
while True:
wait_on = [
self.key_downloads[server_name] for server_name in server_names
if server_name in self.key_downloads
]
if wait_on:
yield defer.DeferredList(wait_on)
else:
break
for server_name, deferred in server_to_deferred.items():
d = ObservableDeferred(deferred)
self.key_downloads[server_name] = d
def rm(r, server_name):
self.key_downloads.pop(server_name, None)
return r
d.addBoth(rm, server_name)
def add_to_queue(self, room_id, events_and_contexts, backfilled,
current_state):
"""Add events to the queue, with the given persist_event options.
"""
queue = self._event_persist_queues.setdefault(room_id, deque())
if queue:
end_item = queue[-1]
if end_item.current_state or current_state:
# We perist events with current_state set to True one at a time
pass
if end_item.backfilled == backfilled:
end_item.events_and_contexts.extend(events_and_contexts)
return end_item.deferred.observe()
deferred = ObservableDeferred(defer.Deferred())
queue.append(
self._EventPersistQueueItem(
events_and_contexts=events_and_contexts,
backfilled=backfilled,
current_state=current_state,
deferred=deferred,
))
return deferred.observe()
def fetch_or_execute(self, txn_key, fn, *args, **kwargs):
"""Fetches the response for this transaction, or executes the given function
to produce a response for this transaction.
Args:
txn_key (str): A key to ensure idempotency should fetch_or_execute be
called again at a later point in time.
fn (function): A function which returns a tuple of
(response_code, response_dict).
*args: Arguments to pass to fn.
**kwargs: Keyword arguments to pass to fn.
Returns:
Deferred which resolves to a tuple of (response_code, response_dict).
"""
try:
return self.transactions[txn_key][0].observe()
except (KeyError, IndexError):
pass # execute the function instead.
deferred = fn(*args, **kwargs)
# We don't add an errback to the raw deferred, so we ask ObservableDeferred
# to swallow the error. This is fine as the error will still be reported
# to the observers.
observable = ObservableDeferred(deferred, consumeErrors=True)
self.transactions[txn_key] = (observable, self.clock.time_msec())
return observable.observe()
def get_server_verify_key(self, server_name, key_ids):
"""Finds a verification key for the server with one of the key ids.
Trys to fetch the key from a trusted perspective server first.
Args:
server_name(str): The name of the server to fetch a key for.
keys_ids (list of str): The key_ids to check for.
"""
cached = yield self.store.get_server_verify_keys(server_name, key_ids)
if cached:
defer.returnValue(cached[0])
return
download = self.key_downloads.get(server_name)
if download is None:
download = self._get_server_verify_key_impl(server_name, key_ids)
download = ObservableDeferred(download, consumeErrors=True)
self.key_downloads[server_name] = download
@download.addBoth
def callback(ret):
del self.key_downloads[server_name]
return ret
r = yield download.observe()
defer.returnValue(r)
def fetch_or_execute(self, txn_key, fn, *args, **kwargs):
"""Fetches the response for this transaction, or executes the given function
to produce a response for this transaction.
Args:
txn_key (str): A key to ensure idempotency should fetch_or_execute be
called again at a later point in time.
fn (function): A function which returns a tuple of
(response_code, response_dict).
*args: Arguments to pass to fn.
**kwargs: Keyword arguments to pass to fn.
Returns:
Deferred which resolves to a tuple of (response_code, response_dict).
"""
if txn_key in self.transactions:
observable = self.transactions[txn_key][0]
else:
# execute the function instead.
deferred = run_in_background(fn, *args, **kwargs)
observable = ObservableDeferred(deferred)
self.transactions[txn_key] = (observable, self.clock.time_msec())
# if the request fails with an exception, remove it
# from the transaction map. This is done to ensure that we don't
# cache transient errors like rate-limiting errors, etc.
def remove_from_map(err):
self.transactions.pop(txn_key, None)
# we deliberately do not propagate the error any further, as we
# expect the observers to have reported it.
deferred.addErrback(remove_from_map)
return make_deferred_yieldable(observable.observe())
def __init__(self, user_id, rooms, current_token, time_now_ms):
self.user_id = user_id
self.rooms = set(rooms)
self.current_token = current_token
self.last_notified_ms = time_now_ms
with PreserveLoggingContext():
self.notify_deferred = ObservableDeferred(defer.Deferred())
def wrapped(*args, **kwargs):
# If we're passed a cache_context then we'll want to call its invalidate()
# whenever we are invalidated
invalidate_callback = kwargs.pop("on_invalidate", None)
# Add temp cache_context so inspect.getcallargs doesn't explode
if self.add_cache_context:
kwargs["cache_context"] = None
arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs)
cache_key = tuple(arg_dict[arg_nm] for arg_nm in self.arg_names)
# Add our own `cache_context` to argument list if the wrapped function
# has asked for one
if self.add_cache_context:
kwargs["cache_context"] = _CacheContext(cache, cache_key)
try:
cached_result_d = cache.get(cache_key, callback=invalidate_callback)
observer = cached_result_d.observe()
if DEBUG_CACHES:
@defer.inlineCallbacks
def check_result(cached_result):
actual_result = yield self.function_to_call(obj, *args, **kwargs)
if actual_result != cached_result:
logger.error(
"Stale cache entry %s%r: cached: %r, actual %r",
self.orig.__name__, cache_key,
cached_result, actual_result,
)
raise ValueError("Stale cache entry")
defer.returnValue(cached_result)
observer.addCallback(check_result)
return preserve_context_over_deferred(observer)
except KeyError:
# Get the sequence number of the cache before reading from the
# database so that we can tell if the cache is invalidated
# while the SELECT is executing (SYN-369)
sequence = cache.sequence
ret = defer.maybeDeferred(
preserve_context_over_fn,
self.function_to_call,
obj, *args, **kwargs
)
def onErr(f):
cache.invalidate(cache_key)
return f
ret.addErrback(onErr)
ret = ObservableDeferred(ret, consumeErrors=True)
cache.update(sequence, cache_key, ret, callback=invalidate_callback)
return preserve_context_over_deferred(ret.observe())
def notify_replication(self):
"""Notify the any replication listeners that there's a new event"""
with PreserveLoggingContext():
deferred = self.replication_deferred
self.replication_deferred = ObservableDeferred(defer.Deferred())
deferred.callback(None)
for cb in self.replication_callbacks:
preserve_fn(cb)()
def set(self, key, deferred):
result = ObservableDeferred(deferred, consumeErrors=True)
self.pending_result_cache[key] = result
def remove(r):
self.pending_result_cache.pop(key, None)
return r
result.addBoth(remove)
return result.observe()
def __init__(self, hs):
self.user_to_user_stream = {}
self.room_to_user_streams = {}
self.hs = hs
self.event_sources = hs.get_event_sources()
self.store = hs.get_datastore()
self.pending_new_room_events = []
self.replication_callbacks = []
self.clock = hs.get_clock()
self.appservice_handler = hs.get_application_service_handler()
if hs.should_send_federation():
self.federation_sender = hs.get_federation_sender()
else:
self.federation_sender = None
self.state_handler = hs.get_state_handler()
self.clock.looping_call(self.remove_expired_streams,
self.UNUSED_STREAM_EXPIRY_MS)
self.replication_deferred = ObservableDeferred(defer.Deferred())
# This is not a very cheap test to perform, but it's only executed
# when rendering the metrics page, which is likely once per minute at
# most when scraping it.
def count_listeners():
all_user_streams = set()
for x in self.room_to_user_streams.values():
all_user_streams |= x
for x in self.user_to_user_stream.values():
all_user_streams.add(x)
return sum(stream.count_listeners() for stream in all_user_streams)
LaterGauge("synapse_notifier_listeners", "", [], count_listeners)
LaterGauge(
"synapse_notifier_rooms",
"",
[],
lambda: count(bool, self.room_to_user_streams.values()),
)
LaterGauge(
"synapse_notifier_users",
"",
[],
lambda: len(self.user_to_user_stream),
)
def __init__(self,
user,
rooms,
current_token,
time_now_ms,
appservice=None):
self.user = str(user)
self.appservice = appservice
self.rooms = set(rooms)
self.current_token = current_token
self.last_notified_ms = time_now_ms
self.notify_deferred = ObservableDeferred(defer.Deferred())
def get_remote_media(self, server_name, media_id):
key = (server_name, media_id)
download = self.downloads.get(key)
if download is None:
download = self._get_remote_media_impl(server_name, media_id)
download = ObservableDeferred(download, consumeErrors=True)
self.downloads[key] = download
@download.addBoth
def callback(media_info):
del self.downloads[key]
return media_info
return download.observe()
def notify(self, stream_key, stream_id, time_now_ms):
"""Notify any listeners for this user of a new event from an
event source.
Args:
stream_key(str): The stream the event came from.
stream_id(str): The new id for the stream the event came from.
time_now_ms(int): The current time in milliseconds.
"""
self.current_token = self.current_token.copy_and_advance(
stream_key, stream_id)
self.last_notified_ms = time_now_ms
noify_deferred = self.notify_deferred
self.notify_deferred = ObservableDeferred(defer.Deferred())
noify_deferred.callback(self.current_token)
def __init__(self, hs):
self.hs = hs
self.user_to_user_stream = {}
self.room_to_user_streams = {}
self.appservice_to_user_streams = {}
self.event_sources = hs.get_event_sources()
self.store = hs.get_datastore()
self.pending_new_room_events = []
self.clock = hs.get_clock()
hs.get_distributor().observe("user_joined_room",
self._user_joined_room)
self.clock.looping_call(self.remove_expired_streams,
self.UNUSED_STREAM_EXPIRY_MS)
self.replication_deferred = ObservableDeferred(defer.Deferred())
# This is not a very cheap test to perform, but it's only executed
# when rendering the metrics page, which is likely once per minute at
# most when scraping it.
def count_listeners():
all_user_streams = set()
for x in self.room_to_user_streams.values():
all_user_streams |= x
for x in self.user_to_user_stream.values():
all_user_streams.add(x)
for x in self.appservice_to_user_streams.values():
all_user_streams |= x
return sum(stream.count_listeners() for stream in all_user_streams)
metrics.register_callback("listeners", count_listeners)
metrics.register_callback(
"rooms",
lambda: count(bool, self.room_to_user_streams.values()),
)
metrics.register_callback(
"users",
lambda: len(self.user_to_user_stream),
)
metrics.register_callback(
"appservices",
lambda: count(bool, self.appservice_to_user_streams.values()),
)
def notify_replication(self):
"""Notify the any replication listeners that there's a new event"""
with PreserveLoggingContext():
deferred = self.replication_deferred
self.replication_deferred = ObservableDeferred(defer.Deferred())
deferred.callback(None)
# the callbacks may well outlast the current request, so we run
# them in the sentinel logcontext.
#
# (ideally it would be up to the callbacks to know if they were
# starting off background processes and drop the logcontext
# accordingly, but that requires more changes)
for cb in self.replication_callbacks:
cb()
def __init__(self, user_id, rooms, current_token, time_now_ms):
self.user_id = user_id
self.rooms = set(rooms)
self.current_token = current_token
# The last token for which we should wake up any streams that have a
# token that comes before it. This gets updated everytime we get poked.
# We start it at the current token since if we get any streams
# that have a token from before we have no idea whether they should be
# woken up or not, so lets just wake them up.
self.last_notified_token = current_token
self.last_notified_ms = time_now_ms
with PreserveLoggingContext():
self.notify_deferred = ObservableDeferred(defer.Deferred())
def wrapped(*args, **kwargs):
arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs)
cache_key = tuple(arg_dict[arg_nm] for arg_nm in self.arg_names)
try:
cached_result_d = cache.get(cache_key)
observer = cached_result_d.observe()
if DEBUG_CACHES:
@defer.inlineCallbacks
def check_result(cached_result):
actual_result = yield self.function_to_call(
obj, *args, **kwargs)
if actual_result != cached_result:
logger.error(
"Stale cache entry %s%r: cached: %r, actual %r",
self.orig.__name__,
cache_key,
cached_result,
actual_result,
)
raise ValueError("Stale cache entry")
defer.returnValue(cached_result)
observer.addCallback(check_result)
return preserve_context_over_deferred(observer)
except KeyError:
# Get the sequence number of the cache before reading from the
# database so that we can tell if the cache is invalidated
# while the SELECT is executing (SYN-369)
sequence = cache.sequence
ret = defer.maybeDeferred(preserve_context_over_fn,
self.function_to_call, obj, *args,
**kwargs)
def onErr(f):
cache.invalidate(cache_key)
return f
ret.addErrback(onErr)
ret = ObservableDeferred(ret, consumeErrors=True)
cache.update(sequence, cache_key, ret)
return preserve_context_over_deferred(ret.observe())
def wrapped(*args, **kwargs):
# If we're passed a cache_context then we'll want to call its invalidate()
# whenever we are invalidated
invalidate_callback = kwargs.pop("on_invalidate", None)
cache_key = get_cache_key(args, kwargs)
# Add our own `cache_context` to argument list if the wrapped function
# has asked for one
if self.add_cache_context:
kwargs["cache_context"] = _CacheContext(cache, cache_key)
try:
cached_result_d = cache.get(cache_key,
callback=invalidate_callback)
if isinstance(cached_result_d, ObservableDeferred):
observer = cached_result_d.observe()
else:
observer = cached_result_d
except KeyError:
ret = defer.maybeDeferred(
logcontext.preserve_fn(self.function_to_call), obj, *args,
**kwargs)
def onErr(f):
cache.invalidate(cache_key)
return f
ret.addErrback(onErr)
# If our cache_key is a string on py2, try to convert to ascii
# to save a bit of space in large caches. Py3 does this
# internally automatically.
if six.PY2 and isinstance(cache_key, string_types):
cache_key = to_ascii(cache_key)
result_d = ObservableDeferred(ret, consumeErrors=True)
cache.set(cache_key, result_d, callback=invalidate_callback)
observer = result_d.observe()
if isinstance(observer, defer.Deferred):
return logcontext.make_deferred_yieldable(observer)
else:
return observer
def set(self, time_now_ms, key, deferred):
self.rotate(time_now_ms)
result = ObservableDeferred(deferred)
self.pending_result_cache[key] = result
def shuffle_along(r):
# When the deferred completes we shuffle it along to the first
# generation of the result cache. So that it will eventually
# expire from the rotation of that cache.
self.next_result_cache[key] = result
self.pending_result_cache.pop(key, None)
result.observe().addBoth(shuffle_along)
return result.observe()
def test_prefill(self):
callcount = [0]
d = defer.succeed(123)
class A(object):
@cached()
def func(self, key):
callcount[0] += 1
return d
a = A()
a.func.prefill(("foo", ), ObservableDeferred(d))
self.assertEquals(a.func("foo").result, d.result)
self.assertEquals(callcount[0], 0)
def set(self, key, deferred):
result = ObservableDeferred(deferred, consumeErrors=True)
self.pending_result_cache[key] = result
def remove(r):
if self.timeout_sec:
self.clock.call_later(
self.timeout_sec,
self.pending_result_cache.pop,
key,
None,
)
else:
self.pending_result_cache.pop(key, None)
return r
result.addBoth(remove)
return result.observe()
def notify(self, stream_key, stream_id, time_now_ms):
"""Notify any listeners for this user of a new event from an
event source.
Args:
stream_key(str): The stream the event came from.
stream_id(str): The new id for the stream the event came from.
time_now_ms(int): The current time in milliseconds.
"""
self.current_token = self.current_token.copy_and_advance(
stream_key, stream_id)
self.last_notified_token = self.current_token
self.last_notified_ms = time_now_ms
noify_deferred = self.notify_deferred
users_woken_by_stream_counter.labels(stream_key).inc()
with PreserveLoggingContext():
self.notify_deferred = ObservableDeferred(defer.Deferred())
noify_deferred.callback(self.current_token)
def fetch_or_execute(self, txn_key, fn, *args, **kwargs):
"""Fetches the response for this transaction, or executes the given function
to produce a response for this transaction.
Args:
txn_key (str): A key to ensure idempotency should fetch_or_execute be
called again at a later point in time.
fn (function): A function which returns a tuple of
(response_code, response_dict).
*args: Arguments to pass to fn.
**kwargs: Keyword arguments to pass to fn.
Returns:
Deferred which resolves to a tuple of (response_code, response_dict).
"""
try:
return self.transactions[txn_key][0].observe()
except (KeyError, IndexError):
pass # execute the function instead.
deferred = fn(*args, **kwargs)
observable = ObservableDeferred(deferred)
self.transactions[txn_key] = (observable, self.clock.time_msec())
return observable.observe()
def fetch_or_execute(self, txn_key, fn, *args, **kwargs):
"""Fetches the response for this transaction, or executes the given function
to produce a response for this transaction.
Args:
txn_key (str): A key to ensure idempotency should fetch_or_execute be
called again at a later point in time.
fn (function): A function which returns a tuple of
(response_code, response_dict).
*args: Arguments to pass to fn.
**kwargs: Keyword arguments to pass to fn.
Returns:
Deferred which resolves to a tuple of (response_code, response_dict).
"""
try:
return self.transactions[txn_key][0].observe()
except (KeyError, IndexError):
pass # execute the function instead.
deferred = fn(*args, **kwargs)
# if the request fails with a Twisted failure, remove it
# from the transaction map. This is done to ensure that we don't
# cache transient errors like rate-limiting errors, etc.
def remove_from_map(err):
self.transactions.pop(txn_key, None)
return err
deferred.addErrback(remove_from_map)
# We don't add any other errbacks to the raw deferred, so we ask
# ObservableDeferred to swallow the error. This is fine as the error will
# still be reported to the observers.
observable = ObservableDeferred(deferred, consumeErrors=True)
self.transactions[txn_key] = (observable, self.clock.time_msec())
return observable.observe()
def set(self, key, deferred):
"""Set the entry for the given key to the given deferred.
*deferred* should run its callbacks in the sentinel logcontext (ie,
you should wrap normal synapse deferreds with
logcontext.run_in_background).
Can return either a new Deferred (which also doesn't follow the synapse
logcontext rules), or, if *deferred* was already complete, the actual
result. You will probably want to make_deferred_yieldable the result.
Args:
key (hashable):
deferred (twisted.internet.defer.Deferred[T):
Returns:
twisted.internet.defer.Deferred[T]|T: a new deferred, or the actual
result.
"""
result = ObservableDeferred(deferred, consumeErrors=True)
self.pending_result_cache[key] = result
def remove(r):
if self.timeout_sec:
self.clock.call_later(
self.timeout_sec,
self.pending_result_cache.pop,
key,
None,
)
else:
self.pending_result_cache.pop(key, None)
return r
result.addBoth(remove)
return result.observe()
def _async_render_GET(self, request):
# XXX: if get_user_by_req fails, what should we do in an async render?
requester = yield self.auth.get_user_by_req(request)
url = request.args.get("url")[0]
if "ts" in request.args:
ts = int(request.args.get("ts")[0])
else:
ts = self.clock.time_msec()
url_tuple = urlparse.urlsplit(url)
for entry in self.url_preview_url_blacklist:
match = True
for attrib in entry:
pattern = entry[attrib]
value = getattr(url_tuple, attrib)
logger.debug(("Matching attrib '%s' with value '%s' against"
" pattern '%s'") % (attrib, value, pattern))
if value is None:
match = False
continue
if pattern.startswith('^'):
if not re.match(pattern, getattr(url_tuple, attrib)):
match = False
continue
else:
if not fnmatch.fnmatch(getattr(url_tuple, attrib),
pattern):
match = False
continue
if match:
logger.warn("URL %s blocked by url_blacklist entry %s", url,
entry)
raise SynapseError(
403, "URL blocked by url pattern blacklist entry",
Codes.UNKNOWN)
# first check the memory cache - good to handle all the clients on this
# HS thundering away to preview the same URL at the same time.
og = self.cache.get(url)
if og:
respond_with_json_bytes(request,
200,
json.dumps(og),
send_cors=True)
return
# then check the URL cache in the DB (which will also provide us with
# historical previews, if we have any)
cache_result = yield self.store.get_url_cache(url, ts)
if (cache_result
and cache_result["download_ts"] + cache_result["expires"] > ts
and cache_result["response_code"] / 100 == 2):
respond_with_json_bytes(request,
200,
cache_result["og"].encode('utf-8'),
send_cors=True)
return
# Ensure only one download for a given URL is active at a time
download = self.downloads.get(url)
if download is None:
download = self._download_url(url, requester.user)
download = ObservableDeferred(download, consumeErrors=True)
self.downloads[url] = download
@download.addBoth
def callback(media_info):
del self.downloads[url]
return media_info
media_info = yield download.observe()
# FIXME: we should probably update our cache now anyway, so that
# even if the OG calculation raises, we don't keep hammering on the
# remote server. For now, leave it uncached to aid debugging OG
# calculation problems
logger.debug("got media_info of '%s'" % media_info)
if _is_media(media_info['media_type']):
dims = yield self.media_repo._generate_local_thumbnails(
media_info['filesystem_id'],
media_info,
url_cache=True,
)
og = {
"og:description":
media_info['download_name'],
"og:image":
"mxc://%s/%s" %
(self.server_name, media_info['filesystem_id']),
"og:image:type":
media_info['media_type'],
"matrix:image:size":
media_info['media_length'],
}
if dims:
og["og:image:width"] = dims['width']
og["og:image:height"] = dims['height']
else:
logger.warn("Couldn't get dims for %s" % url)
# define our OG response for this media
elif _is_html(media_info['media_type']):
# TODO: somehow stop a big HTML tree from exploding synapse's RAM
file = open(media_info['filename'])
body = file.read()
file.close()
# clobber the encoding from the content-type, or default to utf-8
# XXX: this overrides any <meta/> or XML charset headers in the body
# which may pose problems, but so far seems to work okay.
match = re.match(r'.*; *charset=(.*?)(;|$)',
media_info['media_type'], re.I)
encoding = match.group(1) if match else "utf-8"
og = decode_and_calc_og(body, media_info['uri'], encoding)
# pre-cache the image for posterity
# FIXME: it might be cleaner to use the same flow as the main /preview_url
# request itself and benefit from the same caching etc. But for now we
# just rely on the caching on the master request to speed things up.
if 'og:image' in og and og['og:image']:
image_info = yield self._download_url(
_rebase_url(og['og:image'], media_info['uri']),
requester.user)
if _is_media(image_info['media_type']):
# TODO: make sure we don't choke on white-on-transparent images
dims = yield self.media_repo._generate_local_thumbnails(
image_info['filesystem_id'],
image_info,
url_cache=True,
)
if dims:
og["og:image:width"] = dims['width']
og["og:image:height"] = dims['height']
else:
logger.warn("Couldn't get dims for %s" %
og["og:image"])
og["og:image"] = "mxc://%s/%s" % (
self.server_name, image_info['filesystem_id'])
og["og:image:type"] = image_info['media_type']
og["matrix:image:size"] = image_info['media_length']
else:
del og["og:image"]
else:
logger.warn("Failed to find any OG data in %s", url)
og = {}
logger.debug("Calculated OG for %s as %s" % (url, og))
# store OG in ephemeral in-memory cache
self.cache[url] = og
# store OG in history-aware DB cache
yield self.store.store_url_cache(
url,
media_info["response_code"],
media_info["etag"],
media_info["expires"],
json.dumps(og),
media_info["filesystem_id"],
media_info["created_ts"],
)
respond_with_json_bytes(request, 200, json.dumps(og), send_cors=True)
def wrapped(*args, **kwargs):
# If we're passed a cache_context then we'll want to call its invalidate()
# whenever we are invalidated
invalidate_callback = kwargs.pop("on_invalidate", None)
arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs)
keyargs = [arg_dict[arg_nm] for arg_nm in self.arg_names]
list_args = arg_dict[self.list_name]
# cached is a dict arg -> deferred, where deferred results in a
# 2-tuple (`arg`, `result`)
results = {}
cached_defers = {}
missing = []
# If the cache takes a single arg then that is used as the key,
# otherwise a tuple is used.
if num_args == 1:
def cache_get(arg):
return cache.get(arg, callback=invalidate_callback)
else:
key = list(keyargs)
def cache_get(arg):
key[self.list_pos] = arg
return cache.get(tuple(key), callback=invalidate_callback)
for arg in list_args:
try:
res = cache_get(arg)
if not isinstance(res, ObservableDeferred):
results[arg] = res
elif not res.has_succeeded():
res = res.observe()
res.addCallback(lambda r, arg: (arg, r), arg)
cached_defers[arg] = res
else:
results[arg] = res.get_result()
except KeyError:
missing.append(arg)
if missing:
args_to_call = dict(arg_dict)
args_to_call[self.list_name] = missing
ret_d = defer.maybeDeferred(
logcontext.preserve_fn(self.function_to_call),
**args_to_call)
ret_d = ObservableDeferred(ret_d)
# We need to create deferreds for each arg in the list so that
# we can insert the new deferred into the cache.
for arg in missing:
observer = ret_d.observe()
observer.addCallback(lambda r, arg: r.get(arg, None), arg)
observer = ObservableDeferred(observer)
if num_args == 1:
cache.set(arg, observer, callback=invalidate_callback)
def invalidate(f, key):
cache.invalidate(key)
return f
observer.addErrback(invalidate, arg)
else:
key = list(keyargs)
key[self.list_pos] = arg
cache.set(tuple(key),
observer,
callback=invalidate_callback)
def invalidate(f, key):
cache.invalidate(key)
return f
observer.addErrback(invalidate, tuple(key))
res = observer.observe()
res.addCallback(lambda r, arg: (arg, r), arg)
cached_defers[arg] = res
if cached_defers:
def update_results_dict(res):
results.update(res)
return results
return logcontext.make_deferred_yieldable(
defer.gatherResults(
list(cached_defers.values()),
consumeErrors=True,
).addCallback(update_results_dict).addErrback(
unwrapFirstError))
else:
return results
def _async_render_GET(self, request):
# XXX: if get_user_by_req fails, what should we do in an async render?
requester = yield self.auth.get_user_by_req(request)
url = request.args.get("url")[0]
if "ts" in request.args:
ts = int(request.args.get("ts")[0])
else:
ts = self.clock.time_msec()
# XXX: we could move this into _do_preview if we wanted.
url_tuple = urlparse.urlsplit(url)
for entry in self.url_preview_url_blacklist:
match = True
for attrib in entry:
pattern = entry[attrib]
value = getattr(url_tuple, attrib)
logger.debug((
"Matching attrib '%s' with value '%s' against"
" pattern '%s'"
) % (attrib, value, pattern))
if value is None:
match = False
continue
if pattern.startswith('^'):
if not re.match(pattern, getattr(url_tuple, attrib)):
match = False
continue
else:
if not fnmatch.fnmatch(getattr(url_tuple, attrib), pattern):
match = False
continue
if match:
logger.warn(
"URL %s blocked by url_blacklist entry %s", url, entry
)
raise SynapseError(
403, "URL blocked by url pattern blacklist entry",
Codes.UNKNOWN
)
# the in-memory cache:
# * ensures that only one request is active at a time
# * takes load off the DB for the thundering herds
# * also caches any failures (unlike the DB) so we don't keep
# requesting the same endpoint
observable = self._cache.get(url)
if not observable:
download = preserve_fn(self._do_preview)(
url, requester.user, ts,
)
observable = ObservableDeferred(
download,
consumeErrors=True
)
self._cache[url] = observable
else:
logger.info("Returning cached response")
og = yield make_deferred_yieldable(observable.observe())
respond_with_json_bytes(request, 200, og, send_cors=True)
def wrapped(*args, **kwargs):
# If we're passed a cache_context then we'll want to call its invalidate()
# whenever we are invalidated
invalidate_callback = kwargs.pop("on_invalidate", None)
arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs)
keyargs = [arg_dict[arg_nm] for arg_nm in self.arg_names]
list_args = arg_dict[self.list_name]
# cached is a dict arg -> deferred, where deferred results in a
# 2-tuple (`arg`, `result`)
results = {}
cached_defers = {}
missing = []
for arg in list_args:
key = list(keyargs)
key[self.list_pos] = arg
try:
res = cache.get(tuple(key), callback=invalidate_callback)
if not res.has_succeeded():
res = res.observe()
res.addCallback(lambda r, arg: (arg, r), arg)
cached_defers[arg] = res
else:
results[arg] = res.get_result()
except KeyError:
missing.append(arg)
if missing:
sequence = cache.sequence
args_to_call = dict(arg_dict)
args_to_call[self.list_name] = missing
ret_d = defer.maybeDeferred(
preserve_context_over_fn,
self.function_to_call,
**args_to_call
)
ret_d = ObservableDeferred(ret_d)
# We need to create deferreds for each arg in the list so that
# we can insert the new deferred into the cache.
for arg in missing:
with PreserveLoggingContext():
observer = ret_d.observe()
observer.addCallback(lambda r, arg: r.get(arg, None), arg)
observer = ObservableDeferred(observer)
key = list(keyargs)
key[self.list_pos] = arg
cache.update(
sequence, tuple(key), observer,
callback=invalidate_callback
)
def invalidate(f, key):
cache.invalidate(key)
return f
observer.addErrback(invalidate, tuple(key))
res = observer.observe()
res.addCallback(lambda r, arg: (arg, r), arg)
cached_defers[arg] = res
if cached_defers:
def update_results_dict(res):
results.update(res)
return results
return preserve_context_over_deferred(defer.gatherResults(
cached_defers.values(),
consumeErrors=True,
).addCallback(update_results_dict).addErrback(
unwrapFirstError
))
else:
return results
