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Diffstat (limited to 'synapse/storage/database.py')
| -rw-r--r-- | synapse/storage/database.py | 1496 |
1 files changed, 1496 insertions, 0 deletions
diff --git a/synapse/storage/database.py b/synapse/storage/database.py new file mode 100644 index 0000000000..6843b7e7f8 --- /dev/null +++ b/synapse/storage/database.py @@ -0,0 +1,1496 @@ +# -*- coding: utf-8 -*- +# Copyright 2014-2016 OpenMarket Ltd +# Copyright 2017-2018 New Vector Ltd +# Copyright 2019 The Matrix.org Foundation C.I.C. +# +# 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 time +from typing import Iterable, Tuple + +from six import iteritems, iterkeys, itervalues +from six.moves import intern, range + +from prometheus_client import Histogram + +from twisted.internet import defer + +from synapse.api.errors import StoreError +from synapse.logging.context import LoggingContext, make_deferred_yieldable +from synapse.metrics.background_process_metrics import run_as_background_process +from synapse.storage.background_updates import BackgroundUpdater +from synapse.storage.engines import PostgresEngine, Sqlite3Engine +from synapse.util.stringutils import exception_to_unicode + +# import a function which will return a monotonic time, in seconds +try: + # on python 3, use time.monotonic, since time.clock can go backwards + from time import monotonic as monotonic_time +except ImportError: + # ... but python 2 doesn't have it + from time import clock as monotonic_time + +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"]) + + +# Unique indexes which have been added in background updates. Maps from table name +# to the name of the background update which added the unique index to that table. +# +# This is used by the upsert logic to figure out which tables are safe to do a proper +# UPSERT on: until the relevant background update has completed, we +# have to emulate an upsert by locking the table. +# +UNIQUE_INDEX_BACKGROUND_UPDATES = { + "user_ips": "user_ips_device_unique_index", + "device_lists_remote_extremeties": "device_lists_remote_extremeties_unique_idx", + "device_lists_remote_cache": "device_lists_remote_cache_unique_idx", + "event_search": "event_search_event_id_idx", +} + + +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. + + Args: + txn: The database transcation object to wrap. + name (str): The name of this transactions for logging. + database_engine (Sqlite3Engine|PostgresEngine) + after_callbacks(list|None): A list that callbacks will be appended to + that have been added by `call_after` which should be run on + successful completion of the transaction. None indicates that no + callbacks should be allowed to be scheduled to run. + exception_callbacks(list|None): A list that callbacks will be appended + to that have been added by `call_on_exception` which should be run + if transaction ends with an error. None indicates that no callbacks + should be allowed to be scheduled to run. + """ + + __slots__ = [ + "txn", + "name", + "database_engine", + "after_callbacks", + "exception_callbacks", + ] + + def __init__( + self, txn, name, database_engine, after_callbacks=None, exception_callbacks=None + ): + 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_batch(self, sql, args): + if isinstance(self.database_engine, PostgresEngine): + from psycopg2.extras import execute_batch + + self._do_execute(lambda *x: execute_batch(self.txn, *x), sql, args) + else: + for val in args: + self.execute(sql, val) + + 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, duration_secs): + count, cum_time = self.current_counters.get(key, (0, 0)) + count += 1 + cum_time += duration_secs + self.current_counters[key] = (count, cum_time) + + def interval(self, interval_duration_secs, 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_secs, + 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 Database(object): + """Wraps a single physical database and connection pool. + + A single database may be used by multiple data stores. + """ + + _TXN_ID = 0 + + def __init__(self, hs): + self.hs = hs + self._clock = hs.get_clock() + self._db_pool = hs.get_db_pool() + + self.updates = BackgroundUpdater(hs, self) + + 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.database_engine = hs.database_engine + + # A set of tables that are not safe to use native upserts in. + self._unsafe_to_upsert_tables = set(UNIQUE_INDEX_BACKGROUND_UPDATES.keys()) + + # We add the user_directory_search table to the blacklist on SQLite + # because the existing search table does not have an index, making it + # unsafe to use native upserts. + if isinstance(self.database_engine, Sqlite3Engine): + self._unsafe_to_upsert_tables.add("user_directory_search") + + 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] + + for table, update_name in UNIQUE_INDEX_BACKGROUND_UPDATES.items(): + if update_name not in updates: + logger.debug("Now safe to upsert in %s", table) + self._unsafe_to_upsert_tables.discard(table) + + # If there's any updates still running, reschedule to run. + if updates: + 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 = monotonic_time() + + def loop(): + curr = self._current_txn_total_time + prev = self._previous_txn_total_time + self._previous_txn_total_time = curr + + time_now = monotonic_time() + time_then = self._previous_loop_ts + self._previous_loop_ts = time_now + + duration = time_now - time_then + ratio = (curr - prev) / duration + + top_three_counters = self._txn_perf_counters.interval(duration, limit=3) + + perf_logger.info( + "Total database time: %.3f%% {%s}", ratio * 100, top_three_counters + ) + + self._clock.looping_call(loop, 10000) + + def new_transaction( + self, conn, desc, after_callbacks, exception_callbacks, func, *args, **kwargs + ): + start = monotonic_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: + cursor = LoggingTransaction( + conn.cursor(), + name, + self.database_engine, + after_callbacks, + exception_callbacks, + ) + try: + r = func(cursor, *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 + finally: + # we're either about to retry with a new cursor, or we're about to + # release the connection. Once we release the connection, it could + # get used for another query, which might do a conn.rollback(). + # + # In the latter case, even though that probably wouldn't affect the + # results of this transaction, python's sqlite will reset all + # statements on the connection [1], which will make our cursor + # invalid [2]. + # + # In any case, continuing to read rows after commit()ing seems + # dubious from the PoV of ACID transactional semantics + # (sqlite explicitly says that once you commit, you may see rows + # from subsequent updates.) + # + # In psycopg2, cursors are essentially a client-side fabrication - + # all the data is transferred to the client side when the statement + # finishes executing - so in theory we could go on streaming results + # from the cursor, but attempting to do so would make us + # incompatible with sqlite, so let's make sure we're not doing that + # by closing the cursor. + # + # (*named* cursors in psycopg2 are different and are proper server- + # side things, but (a) we don't use them and (b) they are implicitly + # closed by ending the transaction anyway.) + # + # In short, if we haven't finished with the cursor yet, that's a + # problem waiting to bite us. + # + # TL;DR: we're done with the cursor, so we can close it. + # + # [1]: https://github.com/python/cpython/blob/v3.8.0/Modules/_sqlite/connection.c#L465 + # [2]: https://github.com/python/cpython/blob/v3.8.0/Modules/_sqlite/cursor.c#L236 + cursor.close() + except Exception as e: + logger.debug("[TXN FAIL] {%s} %s", name, e) + raise + finally: + end = monotonic_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, duration) + 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.warning("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 + + return 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.warning( + "Starting db connection from sentinel context: metrics will be lost" + ) + parent_context = None + + start_time = monotonic_time() + + def inner_func(conn, *args, **kwargs): + with LoggingContext("runWithConnection", parent_context) as context: + sched_duration_sec = monotonic_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) + + result = yield make_deferred_yieldable( + self._db_pool.runWithConnection(inner_func, *args, **kwargs) + ) + + return 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 + or_ignore : bool stating whether an exception should be raised + when a conflicting row already exists. If True, False will be + returned by the function instead + desc : string giving a description of the transaction + + 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 + return False + return 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 columns 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, + ) + return 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.warning( + "IntegrityError when upserting into %s; retrying: %s", 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,) + + if not values: + # If `values` is empty, then all of the values we care about are in + # the unique key, so there is nothing to UPDATE. We can just do a + # SELECT instead to see if it exists. + sql = "SELECT 1 FROM %s WHERE %s" % ( + table, + " AND ".join(_getwhere(k) for k in keyvalues), + ) + sqlargs = list(keyvalues.values()) + txn.execute(sql, sqlargs) + if txn.fetchall(): + # We have an existing record. + return False + else: + # 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 find any existing 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(insertion_values) + + if not values: + latter = "NOTHING" + else: + allvalues.update(values) + latter = "UPDATE SET " + ", ".join(k + "=EXCLUDED." + k for k in values) + + sql = ("INSERT INTO %s (%s) VALUES (%s) ON CONFLICT (%s) DO %s") % ( + table, + ", ".join(k for k in allvalues), + ", ".join("?" for _ in allvalues), + ", ".join(k for k in keyvalues), + latter, + ) + txn.execute(sql, list(allvalues.values())) + + def simple_upsert_many_txn( + self, txn, table, key_names, key_values, value_names, value_values + ): + """ + Upsert, many times. + + Args: + table (str): The table to upsert into + key_names (list[str]): The key column names. + key_values (list[list]): A list of each row's key column values. + value_names (list[str]): The value column names. If empty, no + values will be used, even if value_values is provided. + value_values (list[list]): A list of each row's value column values. + Returns: + None + """ + if ( + self.database_engine.can_native_upsert + and table not in self._unsafe_to_upsert_tables + ): + return self.simple_upsert_many_txn_native_upsert( + txn, table, key_names, key_values, value_names, value_values + ) + else: + return self.simple_upsert_many_txn_emulated( + txn, table, key_names, key_values, value_names, value_values + ) + + def simple_upsert_many_txn_emulated( + self, txn, table, key_names, key_values, value_names, value_values + ): + """ + Upsert, many times, but without native UPSERT support or batching. + + Args: + table (str): The table to upsert into + key_names (list[str]): The key column names. + key_values (list[list]): A list of each row's key column values. + value_names (list[str]): The value column names. If empty, no + values will be used, even if value_values is provided. + value_values (list[list]): A list of each row's value column values. + Returns: + None + """ + # No value columns, therefore make a blank list so that the following + # zip() works correctly. + if not value_names: + value_values = [() for x in range(len(key_values))] + + for keyv, valv in zip(key_values, value_values): + _keys = {x: y for x, y in zip(key_names, keyv)} + _vals = {x: y for x, y in zip(value_names, valv)} + + self.simple_upsert_txn_emulated(txn, table, _keys, _vals) + + def simple_upsert_many_txn_native_upsert( + self, txn, table, key_names, key_values, value_names, value_values + ): + """ + Upsert, many times, using batching where possible. + + Args: + table (str): The table to upsert into + key_names (list[str]): The key column names. + key_values (list[list]): A list of each row's key column values. + value_names (list[str]): The value column names. If empty, no + values will be used, even if value_values is provided. + value_values (list[list]): A list of each row's value column values. + Returns: + None + """ + allnames = [] + allnames.extend(key_names) + allnames.extend(value_names) + + if not value_names: + # No value columns, therefore make a blank list so that the + # following zip() works correctly. + latter = "NOTHING" + value_values = [() for x in range(len(key_values))] + else: + latter = "UPDATE SET " + ", ".join( + k + "=EXCLUDED." + k for k in value_names + ) + + sql = "INSERT INTO %s (%s) VALUES (%s) ON CONFLICT (%s) DO %s" % ( + table, + ", ".join(k for k in allnames), + ", ".join("?" for _ in allnames), + ", ".join(key_names), + latter, + ) + + args = [] + + for x, y in zip(key_values, value_values): + args.append(tuple(x) + tuple(y)) + + return txn.execute_batch(sql, args) + + 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: + return 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) + + return 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 [] + + clause, values = make_in_list_sql_clause(txn.database_engine, column, iterable) + clauses = [clause] + + for key, value in iteritems(keyvalues): + clauses.append("%s = ?" % (key,)) + values.append(value) + + sql = "SELECT %s FROM %s WHERE %s" % ( + ", ".join(retcols), + table, + " 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), + ) + + txn.execute(sql, list(keyvalues.values())) + return txn.rowcount + + 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 + + Returns: + int: Number rows deleted + """ + if not iterable: + return 0 + + sql = "DELETE FROM %s" % table + + clause, values = make_in_list_sql_clause(txn.database_engine, column, iterable) + clauses = [clause] + + 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 txn.rowcount + + 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 simple_select_list_paginate( + self, + table, + orderby, + start, + limit, + retcols, + filters=None, + keyvalues=None, + order_direction="ASC", + 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 + filters (dict[str, T] | None): + column names and values to filter the rows with, or None to not + apply a WHERE ? LIKE ? clause. + keyvalues (dict[str, T] | None): + column names and values to select the rows with, or None to not + apply a WHERE clause. + orderby (str): Column to order the results by. + start (int): Index to begin the query at. + limit (int): Number of results to return. + retcols (iterable[str]): the names of the columns to return + order_direction (str): Whether the results should be ordered "ASC" or "DESC". + Returns: + defer.Deferred: resolves to list[dict[str, Any]] + """ + return self.runInteraction( + desc, + self.simple_select_list_paginate_txn, + table, + orderby, + start, + limit, + retcols, + filters=filters, + keyvalues=keyvalues, + order_direction=order_direction, + ) + + @classmethod + def simple_select_list_paginate_txn( + cls, + txn, + table, + orderby, + start, + limit, + retcols, + filters=None, + keyvalues=None, + order_direction="ASC", + ): + """ + 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. + + Use `filters` to search attributes using SQL wildcards and/or `keyvalues` to + select attributes with exact matches. All constraints are joined together + using 'AND'. + + Args: + txn : Transaction object + table (str): the table name + orderby (str): Column to order the results by. + start (int): Index to begin the query at. + limit (int): Number of results to return. + retcols (iterable[str]): the names of the columns to return + filters (dict[str, T] | None): + column names and values to filter the rows with, or None to not + apply a WHERE ? LIKE ? clause. + keyvalues (dict[str, T] | None): + column names and values to select the rows with, or None to not + apply a WHERE clause. + order_direction (str): Whether the results should be ordered "ASC" or "DESC". + Returns: + defer.Deferred: resolves to list[dict[str, Any]] + """ + if order_direction not in ["ASC", "DESC"]: + raise ValueError("order_direction must be one of 'ASC' or 'DESC'.") + + where_clause = "WHERE " if filters or keyvalues else "" + arg_list = [] + if filters: + where_clause += " AND ".join("%s LIKE ?" % (k,) for k in filters) + arg_list += list(filters.values()) + where_clause += " AND " if filters and keyvalues else "" + if keyvalues: + where_clause += " AND ".join("%s = ?" % (k,) for k in keyvalues) + arg_list += list(keyvalues.values()) + + sql = "SELECT %s FROM %s %s ORDER BY %s %s LIMIT ? OFFSET ?" % ( + ", ".join(retcols), + table, + where_clause, + orderby, + order_direction, + ) + txn.execute(sql, arg_list + [limit, start]) + + return cls.cursor_to_dict(txn) + + 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) + + +def make_in_list_sql_clause( + database_engine, column: str, iterable: Iterable +) -> Tuple[str, Iterable]: + """Returns an SQL clause that checks the given column is in the iterable. + + On SQLite this expands to `column IN (?, ?, ...)`, whereas on Postgres + it expands to `column = ANY(?)`. While both DBs support the `IN` form, + using the `ANY` form on postgres means that it views queries with + different length iterables as the same, helping the query stats. + + Args: + database_engine + column: Name of the column + iterable: The values to check the column against. + + Returns: + A tuple of SQL query and the args + """ + + if database_engine.supports_using_any_list: + # This should hopefully be faster, but also makes postgres query + # stats easier to understand. + return "%s = ANY(?)" % (column,), [list(iterable)] + else: + return "%s IN (%s)" % (column, ",".join("?" for _ in iterable)), list(iterable) |