synapse-old/synapse/storage/_base.py

1407 lines
49 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2014-2016 OpenMarket Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import logging
import sys
import threading
import time
from six import PY2, iteritems, iterkeys, itervalues
from six.moves import builtins, intern, range
from canonicaljson import json
from prometheus_client import Histogram
from twisted.internet import defer
from synapse.api.errors import StoreError
from synapse.metrics.background_process_metrics import run_as_background_process
from synapse.storage.engines import PostgresEngine
from synapse.util.caches.descriptors import Cache
from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
from synapse.util.stringutils import exception_to_unicode
logger = logging.getLogger(__name__)
try:
MAX_TXN_ID = sys.maxint - 1
except AttributeError:
# python 3 does not have a maximum int value
MAX_TXN_ID = 2**63 - 1
sql_logger = logging.getLogger("synapse.storage.SQL")
transaction_logger = logging.getLogger("synapse.storage.txn")
perf_logger = logging.getLogger("synapse.storage.TIME")
sql_scheduling_timer = Histogram("synapse_storage_schedule_time", "sec")
sql_query_timer = Histogram("synapse_storage_query_time", "sec", ["verb"])
sql_txn_timer = Histogram("synapse_storage_transaction_time", "sec", ["desc"])
class LoggingTransaction(object):
"""An object that almost-transparently proxies for the 'txn' object
passed to the constructor. Adds logging and metrics to the .execute()
method."""
__slots__ = [
"txn", "name", "database_engine", "after_callbacks", "exception_callbacks",
]
def __init__(self, txn, name, database_engine, after_callbacks,
exception_callbacks):
object.__setattr__(self, "txn", txn)
object.__setattr__(self, "name", name)
object.__setattr__(self, "database_engine", database_engine)
object.__setattr__(self, "after_callbacks", after_callbacks)
object.__setattr__(self, "exception_callbacks", exception_callbacks)
def call_after(self, callback, *args, **kwargs):
"""Call the given callback on the main twisted thread after the
transaction has finished. Used to invalidate the caches on the
correct thread.
"""
self.after_callbacks.append((callback, args, kwargs))
def call_on_exception(self, callback, *args, **kwargs):
self.exception_callbacks.append((callback, args, kwargs))
def __getattr__(self, name):
return getattr(self.txn, name)
def __setattr__(self, name, value):
setattr(self.txn, name, value)
def __iter__(self):
return self.txn.__iter__()
def execute(self, sql, *args):
self._do_execute(self.txn.execute, sql, *args)
def executemany(self, sql, *args):
self._do_execute(self.txn.executemany, sql, *args)
def _make_sql_one_line(self, sql):
"Strip newlines out of SQL so that the loggers in the DB are on one line"
return " ".join(l.strip() for l in sql.splitlines() if l.strip())
def _do_execute(self, func, sql, *args):
sql = self._make_sql_one_line(sql)
# TODO(paul): Maybe use 'info' and 'debug' for values?
sql_logger.debug("[SQL] {%s} %s", self.name, sql)
sql = self.database_engine.convert_param_style(sql)
if args:
try:
sql_logger.debug(
"[SQL values] {%s} %r",
self.name, args[0]
)
except Exception:
# Don't let logging failures stop SQL from working
pass
start = time.time()
try:
return func(
sql, *args
)
except Exception as e:
logger.debug("[SQL FAIL] {%s} %s", self.name, e)
raise
finally:
secs = time.time() - start
sql_logger.debug("[SQL time] {%s} %f sec", self.name, secs)
sql_query_timer.labels(sql.split()[0]).observe(secs)
class PerformanceCounters(object):
def __init__(self):
self.current_counters = {}
self.previous_counters = {}
def update(self, key, start_time, end_time=None):
if end_time is None:
end_time = time.time()
duration = end_time - start_time
count, cum_time = self.current_counters.get(key, (0, 0))
count += 1
cum_time += duration
self.current_counters[key] = (count, cum_time)
return end_time
def interval(self, interval_duration, limit=3):
counters = []
for name, (count, cum_time) in iteritems(self.current_counters):
prev_count, prev_time = self.previous_counters.get(name, (0, 0))
counters.append((
(cum_time - prev_time) / interval_duration,
count - prev_count,
name
))
self.previous_counters = dict(self.current_counters)
counters.sort(reverse=True)
top_n_counters = ", ".join(
"%s(%d): %.3f%%" % (name, count, 100 * ratio)
for ratio, count, name in counters[:limit]
)
return top_n_counters
class SQLBaseStore(object):
_TXN_ID = 0
def __init__(self, db_conn, hs):
self.hs = hs
self._clock = hs.get_clock()
self._db_pool = hs.get_db_pool()
self._previous_txn_total_time = 0
self._current_txn_total_time = 0
self._previous_loop_ts = 0
# TODO(paul): These can eventually be removed once the metrics code
# is running in mainline, and we have some nice monitoring frontends
# to watch it
self._txn_perf_counters = PerformanceCounters()
self._get_event_counters = PerformanceCounters()
self._get_event_cache = Cache("*getEvent*", keylen=3,
max_entries=hs.config.event_cache_size)
self._event_fetch_lock = threading.Condition()
self._event_fetch_list = []
self._event_fetch_ongoing = 0
self._pending_ds = []
self.database_engine = hs.database_engine
# A set of tables that are not safe to use native upserts in.
self._unsafe_to_upsert_tables = {"user_ips"}
if self.database_engine.can_native_upsert:
# Check ASAP (and then later, every 1s) to see if we have finished
# background updates of tables that aren't safe to update.
self._clock.call_later(
0.0,
run_as_background_process,
"upsert_safety_check",
self._check_safe_to_upsert
)
@defer.inlineCallbacks
def _check_safe_to_upsert(self):
"""
Is it safe to use native UPSERT?
If there are background updates, we will need to wait, as they may be
the addition of indexes that set the UNIQUE constraint that we require.
If the background updates have not completed, wait 15 sec and check again.
"""
updates = yield self._simple_select_list(
"background_updates",
keyvalues=None,
retcols=["update_name"],
desc="check_background_updates",
)
updates = [x["update_name"] for x in updates]
# The User IPs table in schema #53 was missing a unique index, which we
# run as a background update.
if "user_ips_device_unique_index" not in updates:
self._unsafe_to_upsert_tables.discard("user_ips")
# If there's any tables left to check, reschedule to run.
if self._unsafe_to_upsert_tables:
self._clock.call_later(
15.0,
run_as_background_process,
"upsert_safety_check",
self._check_safe_to_upsert
)
def start_profiling(self):
self._previous_loop_ts = self._clock.time_msec()
def loop():
curr = self._current_txn_total_time
prev = self._previous_txn_total_time
self._previous_txn_total_time = curr
time_now = self._clock.time_msec()
time_then = self._previous_loop_ts
self._previous_loop_ts = time_now
ratio = (curr - prev) / (time_now - time_then)
top_three_counters = self._txn_perf_counters.interval(
time_now - time_then, limit=3
)
top_3_event_counters = self._get_event_counters.interval(
time_now - time_then, limit=3
)
perf_logger.info(
"Total database time: %.3f%% {%s} {%s}",
ratio * 100, top_three_counters, top_3_event_counters
)
self._clock.looping_call(loop, 10000)
def _new_transaction(self, conn, desc, after_callbacks, exception_callbacks,
func, *args, **kwargs):
start = time.time()
txn_id = self._TXN_ID
# We don't really need these to be unique, so lets stop it from
# growing really large.
self._TXN_ID = (self._TXN_ID + 1) % (MAX_TXN_ID)
name = "%s-%x" % (desc, txn_id, )
transaction_logger.debug("[TXN START] {%s}", name)
try:
i = 0
N = 5
while True:
try:
txn = conn.cursor()
txn = LoggingTransaction(
txn, name, self.database_engine, after_callbacks,
exception_callbacks,
)
r = func(txn, *args, **kwargs)
conn.commit()
return r
except self.database_engine.module.OperationalError as e:
# This can happen if the database disappears mid
# transaction.
logger.warning(
"[TXN OPERROR] {%s} %s %d/%d",
name, exception_to_unicode(e), i, N
)
if i < N:
i += 1
try:
conn.rollback()
except self.database_engine.module.Error as e1:
logger.warning(
"[TXN EROLL] {%s} %s",
name, exception_to_unicode(e1),
)
continue
raise
except self.database_engine.module.DatabaseError as e:
if self.database_engine.is_deadlock(e):
logger.warning("[TXN DEADLOCK] {%s} %d/%d", name, i, N)
if i < N:
i += 1
try:
conn.rollback()
except self.database_engine.module.Error as e1:
logger.warning(
"[TXN EROLL] {%s} %s",
name, exception_to_unicode(e1),
)
continue
raise
except Exception as e:
logger.debug("[TXN FAIL] {%s} %s", name, e)
raise
finally:
end = time.time()
duration = end - start
LoggingContext.current_context().add_database_transaction(duration)
transaction_logger.debug("[TXN END] {%s} %f sec", name, duration)
self._current_txn_total_time += duration
self._txn_perf_counters.update(desc, start, end)
sql_txn_timer.labels(desc).observe(duration)
@defer.inlineCallbacks
def runInteraction(self, desc, func, *args, **kwargs):
"""Starts a transaction on the database and runs a given function
Arguments:
desc (str): description of the transaction, for logging and metrics
func (func): callback function, which will be called with a
database transaction (twisted.enterprise.adbapi.Transaction) as
its first argument, followed by `args` and `kwargs`.
args (list): positional args to pass to `func`
kwargs (dict): named args to pass to `func`
Returns:
Deferred: The result of func
"""
after_callbacks = []
exception_callbacks = []
if LoggingContext.current_context() == LoggingContext.sentinel:
logger.warn(
"Starting db txn '%s' from sentinel context",
desc,
)
try:
result = yield self.runWithConnection(
self._new_transaction,
desc, after_callbacks, exception_callbacks, func,
*args, **kwargs
)
for after_callback, after_args, after_kwargs in after_callbacks:
after_callback(*after_args, **after_kwargs)
except: # noqa: E722, as we reraise the exception this is fine.
for after_callback, after_args, after_kwargs in exception_callbacks:
after_callback(*after_args, **after_kwargs)
raise
defer.returnValue(result)
@defer.inlineCallbacks
def runWithConnection(self, func, *args, **kwargs):
"""Wraps the .runWithConnection() method on the underlying db_pool.
Arguments:
func (func): callback function, which will be called with a
database connection (twisted.enterprise.adbapi.Connection) as
its first argument, followed by `args` and `kwargs`.
args (list): positional args to pass to `func`
kwargs (dict): named args to pass to `func`
Returns:
Deferred: The result of func
"""
parent_context = LoggingContext.current_context()
if parent_context == LoggingContext.sentinel:
logger.warn(
"Starting db connection from sentinel context: metrics will be lost",
)
parent_context = None
start_time = time.time()
def inner_func(conn, *args, **kwargs):
with LoggingContext("runWithConnection", parent_context) as context:
sched_duration_sec = time.time() - start_time
sql_scheduling_timer.observe(sched_duration_sec)
context.add_database_scheduled(sched_duration_sec)
if self.database_engine.is_connection_closed(conn):
logger.debug("Reconnecting closed database connection")
conn.reconnect()
return func(conn, *args, **kwargs)
with PreserveLoggingContext():
result = yield self._db_pool.runWithConnection(
inner_func, *args, **kwargs
)
defer.returnValue(result)
@staticmethod
def cursor_to_dict(cursor):
"""Converts a SQL cursor into an list of dicts.
Args:
cursor : The DBAPI cursor which has executed a query.
Returns:
A list of dicts where the key is the column header.
"""
col_headers = list(intern(str(column[0])) for column in cursor.description)
results = list(
dict(zip(col_headers, row)) for row in cursor
)
return results
def _execute(self, desc, decoder, query, *args):
"""Runs a single query for a result set.
Args:
decoder - The function which can resolve the cursor results to
something meaningful.
query - The query string to execute
*args - Query args.
Returns:
The result of decoder(results)
"""
def interaction(txn):
txn.execute(query, args)
if decoder:
return decoder(txn)
else:
return txn.fetchall()
return self.runInteraction(desc, interaction)
# "Simple" SQL API methods that operate on a single table with no JOINs,
# no complex WHERE clauses, just a dict of values for columns.
@defer.inlineCallbacks
def _simple_insert(self, table, values, or_ignore=False,
desc="_simple_insert"):
"""Executes an INSERT query on the named table.
Args:
table : string giving the table name
values : dict of new column names and values for them
Returns:
bool: Whether the row was inserted or not. Only useful when
`or_ignore` is True
"""
try:
yield self.runInteraction(
desc,
self._simple_insert_txn, table, values,
)
except self.database_engine.module.IntegrityError:
# We have to do or_ignore flag at this layer, since we can't reuse
# a cursor after we receive an error from the db.
if not or_ignore:
raise
defer.returnValue(False)
defer.returnValue(True)
@staticmethod
def _simple_insert_txn(txn, table, values):
keys, vals = zip(*values.items())
sql = "INSERT INTO %s (%s) VALUES(%s)" % (
table,
", ".join(k for k in keys),
", ".join("?" for _ in keys)
)
txn.execute(sql, vals)
def _simple_insert_many(self, table, values, desc):
return self.runInteraction(
desc, self._simple_insert_many_txn, table, values
)
@staticmethod
def _simple_insert_many_txn(txn, table, values):
if not values:
return
# This is a *slight* abomination to get a list of tuples of key names
# and a list of tuples of value names.
#
# i.e. [{"a": 1, "b": 2}, {"c": 3, "d": 4}]
# => [("a", "b",), ("c", "d",)] and [(1, 2,), (3, 4,)]
#
# The sort is to ensure that we don't rely on dictionary iteration
# order.
keys, vals = zip(*[
zip(
*(sorted(i.items(), key=lambda kv: kv[0]))
)
for i in values
if i
])
for k in keys:
if k != keys[0]:
raise RuntimeError(
"All items must have the same keys"
)
sql = "INSERT INTO %s (%s) VALUES(%s)" % (
table,
", ".join(k for k in keys[0]),
", ".join("?" for _ in keys[0])
)
txn.executemany(sql, vals)
@defer.inlineCallbacks
def _simple_upsert(
self,
table,
keyvalues,
values,
insertion_values={},
desc="_simple_upsert",
lock=True
):
"""
`lock` should generally be set to True (the default), but can be set
to False if either of the following are true:
* there is a UNIQUE INDEX on the key columns. In this case a conflict
will cause an IntegrityError in which case this function will retry
the update.
* we somehow know that we are the only thread which will be updating
this table.
Args:
table (str): The table to upsert into
keyvalues (dict): The unique key tables and their new values
values (dict): The nonunique columns and their new values
insertion_values (dict): additional key/values to use only when
inserting
lock (bool): True to lock the table when doing the upsert.
Returns:
Deferred(None or bool): Native upserts always return None. Emulated
upserts return True if a new entry was created, False if an existing
one was updated.
"""
attempts = 0
while True:
try:
result = yield self.runInteraction(
desc,
self._simple_upsert_txn,
table,
keyvalues,
values,
insertion_values,
lock=lock,
)
defer.returnValue(result)
except self.database_engine.module.IntegrityError as e:
attempts += 1
if attempts >= 5:
# don't retry forever, because things other than races
# can cause IntegrityErrors
raise
# presumably we raced with another transaction: let's retry.
logger.warn(
"%s when upserting into %s; retrying: %s", e.__name__, table, e
)
def _simple_upsert_txn(
self,
txn,
table,
keyvalues,
values,
insertion_values={},
lock=True,
):
"""
Pick the UPSERT method which works best on the platform. Either the
native one (Pg9.5+, recent SQLites), or fall back to an emulated method.
Args:
txn: The transaction to use.
table (str): The table to upsert into
keyvalues (dict): The unique key tables and their new values
values (dict): The nonunique columns and their new values
insertion_values (dict): additional key/values to use only when
inserting
lock (bool): True to lock the table when doing the upsert.
Returns:
None or bool: Native upserts always return None. Emulated
upserts return True if a new entry was created, False if an existing
one was updated.
"""
if (
self.database_engine.can_native_upsert
and table not in self._unsafe_to_upsert_tables
):
return self._simple_upsert_txn_native_upsert(
txn,
table,
keyvalues,
values,
insertion_values=insertion_values,
)
else:
return self._simple_upsert_txn_emulated(
txn,
table,
keyvalues,
values,
insertion_values=insertion_values,
lock=lock,
)
def _simple_upsert_txn_emulated(
self, txn, table, keyvalues, values, insertion_values={}, lock=True
):
"""
Args:
table (str): The table to upsert into
keyvalues (dict): The unique key tables and their new values
values (dict): The nonunique columns and their new values
insertion_values (dict): additional key/values to use only when
inserting
lock (bool): True to lock the table when doing the upsert.
Returns:
bool: Return True if a new entry was created, False if an existing
one was updated.
"""
# We need to lock the table :(, unless we're *really* careful
if lock:
self.database_engine.lock_table(txn, table)
def _getwhere(key):
# If the value we're passing in is None (aka NULL), we need to use
# IS, not =, as NULL = NULL equals NULL (False).
if keyvalues[key] is None:
return "%s IS ?" % (key,)
else:
return "%s = ?" % (key,)
# First try to update.
sql = "UPDATE %s SET %s WHERE %s" % (
table,
", ".join("%s = ?" % (k,) for k in values),
" AND ".join(_getwhere(k) for k in keyvalues)
)
sqlargs = list(values.values()) + list(keyvalues.values())
txn.execute(sql, sqlargs)
if txn.rowcount > 0:
# successfully updated at least one row.
return False
# We didn't update any rows so insert a new one
allvalues = {}
allvalues.update(keyvalues)
allvalues.update(values)
allvalues.update(insertion_values)
sql = "INSERT INTO %s (%s) VALUES (%s)" % (
table,
", ".join(k for k in allvalues),
", ".join("?" for _ in allvalues),
)
txn.execute(sql, list(allvalues.values()))
# successfully inserted
return True
def _simple_upsert_txn_native_upsert(
self, txn, table, keyvalues, values, insertion_values={}
):
"""
Use the native UPSERT functionality in recent PostgreSQL versions.
Args:
table (str): The table to upsert into
keyvalues (dict): The unique key tables and their new values
values (dict): The nonunique columns and their new values
insertion_values (dict): additional key/values to use only when
inserting
Returns:
None
"""
allvalues = {}
allvalues.update(keyvalues)
allvalues.update(values)
allvalues.update(insertion_values)
sql = (
"INSERT INTO %s (%s) VALUES (%s) "
"ON CONFLICT (%s) DO UPDATE SET %s"
) % (
table,
", ".join(k for k in allvalues),
", ".join("?" for _ in allvalues),
", ".join(k for k in keyvalues),
", ".join(k + "=EXCLUDED." + k for k in values),
)
txn.execute(sql, list(allvalues.values()))
def _simple_select_one(self, table, keyvalues, retcols,
allow_none=False, desc="_simple_select_one"):
"""Executes a SELECT query on the named table, which is expected to
return a single row, returning multiple columns from it.
Args:
table : string giving the table name
keyvalues : dict of column names and values to select the row with
retcols : list of strings giving the names of the columns to return
allow_none : If true, return None instead of failing if the SELECT
statement returns no rows
"""
return self.runInteraction(
desc,
self._simple_select_one_txn,
table, keyvalues, retcols, allow_none,
)
def _simple_select_one_onecol(self, table, keyvalues, retcol,
allow_none=False,
desc="_simple_select_one_onecol"):
"""Executes a SELECT query on the named table, which is expected to
return a single row, returning a single column from it.
Args:
table : string giving the table name
keyvalues : dict of column names and values to select the row with
retcol : string giving the name of the column to return
"""
return self.runInteraction(
desc,
self._simple_select_one_onecol_txn,
table, keyvalues, retcol, allow_none=allow_none,
)
@classmethod
def _simple_select_one_onecol_txn(cls, txn, table, keyvalues, retcol,
allow_none=False):
ret = cls._simple_select_onecol_txn(
txn,
table=table,
keyvalues=keyvalues,
retcol=retcol,
)
if ret:
return ret[0]
else:
if allow_none:
return None
else:
raise StoreError(404, "No row found")
@staticmethod
def _simple_select_onecol_txn(txn, table, keyvalues, retcol):
sql = (
"SELECT %(retcol)s FROM %(table)s"
) % {
"retcol": retcol,
"table": table,
}
if keyvalues:
sql += " WHERE %s" % " AND ".join("%s = ?" % k for k in iterkeys(keyvalues))
txn.execute(sql, list(keyvalues.values()))
else:
txn.execute(sql)
return [r[0] for r in txn]
def _simple_select_onecol(self, table, keyvalues, retcol,
desc="_simple_select_onecol"):
"""Executes a SELECT query on the named table, which returns a list
comprising of the values of the named column from the selected rows.
Args:
table (str): table name
keyvalues (dict|None): column names and values to select the rows with
retcol (str): column whos value we wish to retrieve.
Returns:
Deferred: Results in a list
"""
return self.runInteraction(
desc,
self._simple_select_onecol_txn,
table, keyvalues, retcol
)
def _simple_select_list(self, table, keyvalues, retcols,
desc="_simple_select_list"):
"""Executes a SELECT query on the named table, which may return zero or
more rows, returning the result as a list of dicts.
Args:
table (str): the table name
keyvalues (dict[str, Any] | None):
column names and values to select the rows with, or None to not
apply a WHERE clause.
retcols (iterable[str]): the names of the columns to return
Returns:
defer.Deferred: resolves to list[dict[str, Any]]
"""
return self.runInteraction(
desc,
self._simple_select_list_txn,
table, keyvalues, retcols
)
@classmethod
def _simple_select_list_txn(cls, txn, table, keyvalues, retcols):
"""Executes a SELECT query on the named table, which may return zero or
more rows, returning the result as a list of dicts.
Args:
txn : Transaction object
table (str): the table name
keyvalues (dict[str, T] | None):
column names and values to select the rows with, or None to not
apply a WHERE clause.
retcols (iterable[str]): the names of the columns to return
"""
if keyvalues:
sql = "SELECT %s FROM %s WHERE %s" % (
", ".join(retcols),
table,
" AND ".join("%s = ?" % (k, ) for k in keyvalues)
)
txn.execute(sql, list(keyvalues.values()))
else:
sql = "SELECT %s FROM %s" % (
", ".join(retcols),
table
)
txn.execute(sql)
return cls.cursor_to_dict(txn)
@defer.inlineCallbacks
def _simple_select_many_batch(self, table, column, iterable, retcols,
keyvalues={}, desc="_simple_select_many_batch",
batch_size=100):
"""Executes a SELECT query on the named table, which may return zero or
more rows, returning the result as a list of dicts.
Filters rows by if value of `column` is in `iterable`.
Args:
table : string giving the table name
column : column name to test for inclusion against `iterable`
iterable : list
keyvalues : dict of column names and values to select the rows with
retcols : list of strings giving the names of the columns to return
"""
results = []
if not iterable:
defer.returnValue(results)
# iterables can not be sliced, so convert it to a list first
it_list = list(iterable)
chunks = [
it_list[i:i + batch_size]
for i in range(0, len(it_list), batch_size)
]
for chunk in chunks:
rows = yield self.runInteraction(
desc,
self._simple_select_many_txn,
table, column, chunk, keyvalues, retcols
)
results.extend(rows)
defer.returnValue(results)
@classmethod
def _simple_select_many_txn(cls, txn, table, column, iterable, keyvalues, retcols):
"""Executes a SELECT query on the named table, which may return zero or
more rows, returning the result as a list of dicts.
Filters rows by if value of `column` is in `iterable`.
Args:
txn : Transaction object
table : string giving the table name
column : column name to test for inclusion against `iterable`
iterable : list
keyvalues : dict of column names and values to select the rows with
retcols : list of strings giving the names of the columns to return
"""
if not iterable:
return []
sql = "SELECT %s FROM %s" % (", ".join(retcols), table)
clauses = []
values = []
clauses.append(
"%s IN (%s)" % (column, ",".join("?" for _ in iterable))
)
values.extend(iterable)
for key, value in iteritems(keyvalues):
clauses.append("%s = ?" % (key,))
values.append(value)
if clauses:
sql = "%s WHERE %s" % (
sql,
" AND ".join(clauses),
)
txn.execute(sql, values)
return cls.cursor_to_dict(txn)
def _simple_update(self, table, keyvalues, updatevalues, desc):
return self.runInteraction(
desc,
self._simple_update_txn,
table, keyvalues, updatevalues,
)
@staticmethod
def _simple_update_txn(txn, table, keyvalues, updatevalues):
if keyvalues:
where = "WHERE %s" % " AND ".join("%s = ?" % k for k in iterkeys(keyvalues))
else:
where = ""
update_sql = "UPDATE %s SET %s %s" % (
table,
", ".join("%s = ?" % (k,) for k in updatevalues),
where,
)
txn.execute(
update_sql,
list(updatevalues.values()) + list(keyvalues.values())
)
return txn.rowcount
def _simple_update_one(self, table, keyvalues, updatevalues,
desc="_simple_update_one"):
"""Executes an UPDATE query on the named table, setting new values for
columns in a row matching the key values.
Args:
table : string giving the table name
keyvalues : dict of column names and values to select the row with
updatevalues : dict giving column names and values to update
retcols : optional list of column names to return
If present, retcols gives a list of column names on which to perform
a SELECT statement *before* performing the UPDATE statement. The values
of these will be returned in a dict.
These are performed within the same transaction, allowing an atomic
get-and-set. This can be used to implement compare-and-set by putting
the update column in the 'keyvalues' dict as well.
"""
return self.runInteraction(
desc,
self._simple_update_one_txn,
table, keyvalues, updatevalues,
)
@classmethod
def _simple_update_one_txn(cls, txn, table, keyvalues, updatevalues):
rowcount = cls._simple_update_txn(txn, table, keyvalues, updatevalues)
if rowcount == 0:
raise StoreError(404, "No row found (%s)" % (table,))
if rowcount > 1:
raise StoreError(500, "More than one row matched (%s)" % (table,))
@staticmethod
def _simple_select_one_txn(txn, table, keyvalues, retcols,
allow_none=False):
select_sql = "SELECT %s FROM %s WHERE %s" % (
", ".join(retcols),
table,
" AND ".join("%s = ?" % (k,) for k in keyvalues)
)
txn.execute(select_sql, list(keyvalues.values()))
row = txn.fetchone()
if not row:
if allow_none:
return None
raise StoreError(404, "No row found (%s)" % (table,))
if txn.rowcount > 1:
raise StoreError(500, "More than one row matched (%s)" % (table,))
return dict(zip(retcols, row))
def _simple_delete_one(self, table, keyvalues, desc="_simple_delete_one"):
"""Executes a DELETE query on the named table, expecting to delete a
single row.
Args:
table : string giving the table name
keyvalues : dict of column names and values to select the row with
"""
return self.runInteraction(
desc, self._simple_delete_one_txn, table, keyvalues
)
@staticmethod
def _simple_delete_one_txn(txn, table, keyvalues):
"""Executes a DELETE query on the named table, expecting to delete a
single row.
Args:
table : string giving the table name
keyvalues : dict of column names and values to select the row with
"""
sql = "DELETE FROM %s WHERE %s" % (
table,
" AND ".join("%s = ?" % (k, ) for k in keyvalues)
)
txn.execute(sql, list(keyvalues.values()))
if txn.rowcount == 0:
raise StoreError(404, "No row found (%s)" % (table,))
if txn.rowcount > 1:
raise StoreError(500, "More than one row matched (%s)" % (table,))
def _simple_delete(self, table, keyvalues, desc):
return self.runInteraction(
desc, self._simple_delete_txn, table, keyvalues
)
@staticmethod
def _simple_delete_txn(txn, table, keyvalues):
sql = "DELETE FROM %s WHERE %s" % (
table,
" AND ".join("%s = ?" % (k, ) for k in keyvalues)
)
return txn.execute(sql, list(keyvalues.values()))
def _simple_delete_many(self, table, column, iterable, keyvalues, desc):
return self.runInteraction(
desc, self._simple_delete_many_txn, table, column, iterable, keyvalues
)
@staticmethod
def _simple_delete_many_txn(txn, table, column, iterable, keyvalues):
"""Executes a DELETE query on the named table.
Filters rows by if value of `column` is in `iterable`.
Args:
txn : Transaction object
table : string giving the table name
column : column name to test for inclusion against `iterable`
iterable : list
keyvalues : dict of column names and values to select the rows with
"""
if not iterable:
return
sql = "DELETE FROM %s" % table
clauses = []
values = []
clauses.append(
"%s IN (%s)" % (column, ",".join("?" for _ in iterable))
)
values.extend(iterable)
for key, value in iteritems(keyvalues):
clauses.append("%s = ?" % (key,))
values.append(value)
if clauses:
sql = "%s WHERE %s" % (
sql,
" AND ".join(clauses),
)
return txn.execute(sql, values)
def _get_cache_dict(self, db_conn, table, entity_column, stream_column,
max_value, limit=100000):
# Fetch a mapping of room_id -> max stream position for "recent" rooms.
# It doesn't really matter how many we get, the StreamChangeCache will
# do the right thing to ensure it respects the max size of cache.
sql = (
"SELECT %(entity)s, MAX(%(stream)s) FROM %(table)s"
" WHERE %(stream)s > ? - %(limit)s"
" GROUP BY %(entity)s"
) % {
"table": table,
"entity": entity_column,
"stream": stream_column,
"limit": limit,
}
sql = self.database_engine.convert_param_style(sql)
txn = db_conn.cursor()
txn.execute(sql, (int(max_value),))
cache = {
row[0]: int(row[1])
for row in txn
}
txn.close()
if cache:
min_val = min(itervalues(cache))
else:
min_val = max_value
return cache, min_val
def _invalidate_cache_and_stream(self, txn, cache_func, keys):
"""Invalidates the cache and adds it to the cache stream so slaves
will know to invalidate their caches.
This should only be used to invalidate caches where slaves won't
otherwise know from other replication streams that the cache should
be invalidated.
"""
txn.call_after(cache_func.invalidate, keys)
if isinstance(self.database_engine, PostgresEngine):
# get_next() returns a context manager which is designed to wrap
# the transaction. However, we want to only get an ID when we want
# to use it, here, so we need to call __enter__ manually, and have
# __exit__ called after the transaction finishes.
ctx = self._cache_id_gen.get_next()
stream_id = ctx.__enter__()
txn.call_on_exception(ctx.__exit__, None, None, None)
txn.call_after(ctx.__exit__, None, None, None)
txn.call_after(self.hs.get_notifier().on_new_replication_data)
self._simple_insert_txn(
txn,
table="cache_invalidation_stream",
values={
"stream_id": stream_id,
"cache_func": cache_func.__name__,
"keys": list(keys),
"invalidation_ts": self.clock.time_msec(),
}
)
def get_all_updated_caches(self, last_id, current_id, limit):
if last_id == current_id:
return defer.succeed([])
def get_all_updated_caches_txn(txn):
# We purposefully don't bound by the current token, as we want to
# send across cache invalidations as quickly as possible. Cache
# invalidations are idempotent, so duplicates are fine.
sql = (
"SELECT stream_id, cache_func, keys, invalidation_ts"
" FROM cache_invalidation_stream"
" WHERE stream_id > ? ORDER BY stream_id ASC LIMIT ?"
)
txn.execute(sql, (last_id, limit,))
return txn.fetchall()
return self.runInteraction(
"get_all_updated_caches", get_all_updated_caches_txn
)
def get_cache_stream_token(self):
if self._cache_id_gen:
return self._cache_id_gen.get_current_token()
else:
return 0
def _simple_select_list_paginate(self, table, keyvalues, pagevalues, retcols,
desc="_simple_select_list_paginate"):
"""Executes a SELECT query on the named table with start and limit,
of row numbers, which may return zero or number of rows from start to limit,
returning the result as a list of dicts.
Args:
table (str): the table name
keyvalues (dict[str, Any] | None):
column names and values to select the rows with, or None to not
apply a WHERE clause.
retcols (iterable[str]): the names of the columns to return
order (str): order the select by this column
start (int): start number to begin the query from
limit (int): number of rows to reterive
Returns:
defer.Deferred: resolves to list[dict[str, Any]]
"""
return self.runInteraction(
desc,
self._simple_select_list_paginate_txn,
table, keyvalues, pagevalues, retcols
)
@classmethod
def _simple_select_list_paginate_txn(cls, txn, table, keyvalues, pagevalues, retcols):
"""Executes a SELECT query on the named table with start and limit,
of row numbers, which may return zero or number of rows from start to limit,
returning the result as a list of dicts.
Args:
txn : Transaction object
table (str): the table name
keyvalues (dict[str, T] | None):
column names and values to select the rows with, or None to not
apply a WHERE clause.
pagevalues ([]):
order (str): order the select by this column
start (int): start number to begin the query from
limit (int): number of rows to reterive
retcols (iterable[str]): the names of the columns to return
Returns:
defer.Deferred: resolves to list[dict[str, Any]]
"""
if keyvalues:
sql = "SELECT %s FROM %s WHERE %s ORDER BY %s" % (
", ".join(retcols),
table,
" AND ".join("%s = ?" % (k,) for k in keyvalues),
" ? ASC LIMIT ? OFFSET ?"
)
txn.execute(sql, list(keyvalues.values()) + list(pagevalues))
else:
sql = "SELECT %s FROM %s ORDER BY %s" % (
", ".join(retcols),
table,
" ? ASC LIMIT ? OFFSET ?"
)
txn.execute(sql, pagevalues)
return cls.cursor_to_dict(txn)
@defer.inlineCallbacks
def get_user_list_paginate(self, table, keyvalues, pagevalues, retcols,
desc="get_user_list_paginate"):
"""Get a list of users from start row to a limit number of rows. This will
return a json object with users and total number of users in users list.
Args:
table (str): the table name
keyvalues (dict[str, Any] | None):
column names and values to select the rows with, or None to not
apply a WHERE clause.
pagevalues ([]):
order (str): order the select by this column
start (int): start number to begin the query from
limit (int): number of rows to reterive
retcols (iterable[str]): the names of the columns to return
Returns:
defer.Deferred: resolves to json object {list[dict[str, Any]], count}
"""
users = yield self.runInteraction(
desc,
self._simple_select_list_paginate_txn,
table, keyvalues, pagevalues, retcols
)
count = yield self.runInteraction(
desc,
self.get_user_count_txn
)
retval = {
"users": users,
"total": count
}
defer.returnValue(retval)
def get_user_count_txn(self, txn):
"""Get a total number of registered users in the users list.
Args:
txn : Transaction object
Returns:
int : number of users
"""
sql_count = "SELECT COUNT(*) FROM users WHERE is_guest = 0;"
txn.execute(sql_count)
return txn.fetchone()[0]
def _simple_search_list(self, table, term, col, retcols,
desc="_simple_search_list"):
"""Executes a SELECT query on the named table, which may return zero or
more rows, returning the result as a list of dicts.
Args:
table (str): the table name
term (str | None):
term for searching the table matched to a column.
col (str): column to query term should be matched to
retcols (iterable[str]): the names of the columns to return
Returns:
defer.Deferred: resolves to list[dict[str, Any]] or None
"""
return self.runInteraction(
desc,
self._simple_search_list_txn,
table, term, col, retcols
)
@classmethod
def _simple_search_list_txn(cls, txn, table, term, col, retcols):
"""Executes a SELECT query on the named table, which may return zero or
more rows, returning the result as a list of dicts.
Args:
txn : Transaction object
table (str): the table name
term (str | None):
term for searching the table matched to a column.
col (str): column to query term should be matched to
retcols (iterable[str]): the names of the columns to return
Returns:
defer.Deferred: resolves to list[dict[str, Any]] or None
"""
if term:
sql = "SELECT %s FROM %s WHERE %s LIKE ?" % (
", ".join(retcols),
table,
col
)
termvalues = ["%%" + term + "%%"]
txn.execute(sql, termvalues)
else:
return 0
return cls.cursor_to_dict(txn)
class _RollbackButIsFineException(Exception):
""" This exception is used to rollback a transaction without implying
something went wrong.
"""
pass
def db_to_json(db_content):
"""
Take some data from a database row and return a JSON-decoded object.
Args:
db_content (memoryview|buffer|bytes|bytearray|unicode)
"""
# psycopg2 on Python 3 returns memoryview objects, which we need to
# cast to bytes to decode
if isinstance(db_content, memoryview):
db_content = db_content.tobytes()
# psycopg2 on Python 2 returns buffer objects, which we need to cast to
# bytes to decode
if PY2 and isinstance(db_content, builtins.buffer):
db_content = bytes(db_content)
# Decode it to a Unicode string before feeding it to json.loads, so we
# consistenty get a Unicode-containing object out.
if isinstance(db_content, (bytes, bytearray)):
db_content = db_content.decode('utf8')
try:
return json.loads(db_content)
except Exception:
logging.warning("Tried to decode '%r' as JSON and failed", db_content)
raise