761 lines
25 KiB
Python
761 lines
25 KiB
Python
# -*- coding: utf-8 -*-
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# Copyright 2014, 2015 OpenMarket Ltd
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import logging
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from synapse.api.errors import StoreError
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from synapse.events import FrozenEvent
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from synapse.events.utils import prune_event
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from synapse.util.logutils import log_function
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from synapse.util.logcontext import PreserveLoggingContext, LoggingContext
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from twisted.internet import defer
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import collections
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import json
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import sys
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import time
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logger = logging.getLogger(__name__)
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sql_logger = logging.getLogger("synapse.storage.SQL")
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transaction_logger = logging.getLogger("synapse.storage.txn")
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class LoggingTransaction(object):
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"""An object that almost-transparently proxies for the 'txn' object
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passed to the constructor. Adds logging to the .execute() method."""
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__slots__ = ["txn", "name"]
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def __init__(self, txn, name):
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object.__setattr__(self, "txn", txn)
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object.__setattr__(self, "name", name)
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def __getattr__(self, name):
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return getattr(self.txn, name)
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def __setattr__(self, name, value):
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setattr(self.txn, name, value)
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def execute(self, sql, *args, **kwargs):
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# TODO(paul): Maybe use 'info' and 'debug' for values?
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sql_logger.debug("[SQL] {%s} %s", self.name, sql)
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try:
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if args and args[0]:
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values = args[0]
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sql_logger.debug(
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"[SQL values] {%s} " + ", ".join(("<%r>",) * len(values)),
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self.name,
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*values
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)
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except:
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# Don't let logging failures stop SQL from working
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pass
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start = time.time() * 1000
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try:
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return self.txn.execute(
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sql, *args, **kwargs
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)
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except:
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logger.exception("[SQL FAIL] {%s}", self.name)
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raise
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finally:
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end = time.time() * 1000
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sql_logger.debug("[SQL time] {%s} %f", self.name, end - start)
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class SQLBaseStore(object):
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_TXN_ID = 0
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def __init__(self, hs):
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self.hs = hs
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self._db_pool = hs.get_db_pool()
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self._clock = hs.get_clock()
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self._previous_txn_total_time = 0
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self._current_txn_total_time = 0
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self._previous_loop_ts = 0
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self._txn_perf_counters = {}
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self._previous_txn_perf_counters = {}
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def start_profiling(self):
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self._previous_loop_ts = self._clock.time_msec()
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def loop():
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curr = self._current_txn_total_time
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prev = self._previous_txn_total_time
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self._previous_txn_total_time = curr
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time_now = self._clock.time_msec()
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time_then = self._previous_loop_ts
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self._previous_loop_ts = time_now
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ratio = (curr - prev)/(time_now - time_then)
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txn_counters = []
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for name, (count, cum_time) in self._txn_perf_counters.items():
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prev_count, prev_time = self._previous_txn_perf_counters.get(
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name, (0,0)
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)
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txn_counters.append((
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(cum_time - prev_time) / (time_now - time_then),
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count - prev_count,
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name
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))
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self._previous_txn_perf_counters = dict(self._txn_perf_counters)
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txn_counters.sort(reverse=True)
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top_three_counters = ", ".join(
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"%s(%d): %.3f%%" % (name, count, 100 * ratio)
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for ratio, count, name in txn_counters[:3]
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)
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logger.info(
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"Total database time: %.3f%% {%s}",
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ratio * 100, top_three_counters
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)
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self._clock.looping_call(loop, 10000)
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@defer.inlineCallbacks
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def runInteraction(self, desc, func, *args, **kwargs):
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"""Wraps the .runInteraction() method on the underlying db_pool."""
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current_context = LoggingContext.current_context()
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def inner_func(txn, *args, **kwargs):
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with LoggingContext("runInteraction") as context:
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current_context.copy_to(context)
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start = time.time() * 1000
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txn_id = self._TXN_ID
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# We don't really need these to be unique, so lets stop it from
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# growing really large.
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self._TXN_ID = (self._TXN_ID + 1) % (sys.maxint - 1)
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name = "%s-%x" % (desc, txn_id, )
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transaction_logger.debug("[TXN START] {%s}", name)
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try:
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return func(LoggingTransaction(txn, name), *args, **kwargs)
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except:
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logger.exception("[TXN FAIL] {%s}", name)
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raise
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finally:
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end = time.time() * 1000
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transaction_logger.debug(
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"[TXN END] {%s} %f",
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name, end - start
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)
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self._current_txn_total_time += end - start
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count, cum_time = self._txn_perf_counters.get(desc, (0,0))
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count += 1
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cum_time += end - start
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self._txn_perf_counters[desc] = (count, cum_time)
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with PreserveLoggingContext():
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result = yield self._db_pool.runInteraction(
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inner_func, *args, **kwargs
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)
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defer.returnValue(result)
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def cursor_to_dict(self, cursor):
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"""Converts a SQL cursor into an list of dicts.
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Args:
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cursor : The DBAPI cursor which has executed a query.
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Returns:
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A list of dicts where the key is the column header.
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"""
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col_headers = list(column[0] for column in cursor.description)
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results = list(
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dict(zip(col_headers, row)) for row in cursor.fetchall()
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)
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return results
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def _execute(self, decoder, query, *args):
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"""Runs a single query for a result set.
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Args:
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decoder - The function which can resolve the cursor results to
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something meaningful.
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query - The query string to execute
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*args - Query args.
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Returns:
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The result of decoder(results)
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"""
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def interaction(txn):
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cursor = txn.execute(query, args)
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if decoder:
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return decoder(cursor)
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else:
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return cursor.fetchall()
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return self.runInteraction("_execute", interaction)
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def _execute_and_decode(self, query, *args):
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return self._execute(self.cursor_to_dict, query, *args)
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# "Simple" SQL API methods that operate on a single table with no JOINs,
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# no complex WHERE clauses, just a dict of values for columns.
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def _simple_insert(self, table, values, or_replace=False, or_ignore=False):
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"""Executes an INSERT query on the named table.
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Args:
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table : string giving the table name
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values : dict of new column names and values for them
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or_replace : bool; if True performs an INSERT OR REPLACE
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"""
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return self.runInteraction(
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"_simple_insert",
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self._simple_insert_txn, table, values, or_replace=or_replace,
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or_ignore=or_ignore,
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)
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@log_function
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def _simple_insert_txn(self, txn, table, values, or_replace=False,
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or_ignore=False):
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sql = "%s INTO %s (%s) VALUES(%s)" % (
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("INSERT OR REPLACE" if or_replace else
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"INSERT OR IGNORE" if or_ignore else "INSERT"),
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table,
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", ".join(k for k in values),
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", ".join("?" for k in values)
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)
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logger.debug(
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"[SQL] %s Args=%s",
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sql, values.values(),
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)
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txn.execute(sql, values.values())
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return txn.lastrowid
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def _simple_upsert(self, table, keyvalues, values):
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"""
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Args:
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table (str): The table to upsert into
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keyvalues (dict): The unique key tables and their new values
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values (dict): The nonunique columns and their new values
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Returns: A deferred
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"""
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return self.runInteraction(
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"_simple_upsert",
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self._simple_upsert_txn, table, keyvalues, values
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)
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def _simple_upsert_txn(self, txn, table, keyvalues, values):
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# Try to update
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sql = "UPDATE %s SET %s WHERE %s" % (
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table,
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", ".join("%s = ?" % (k,) for k in values),
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" AND ".join("%s = ?" % (k,) for k in keyvalues)
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)
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sqlargs = values.values() + keyvalues.values()
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logger.debug(
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"[SQL] %s Args=%s",
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sql, sqlargs,
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)
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txn.execute(sql, sqlargs)
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if txn.rowcount == 0:
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# We didn't update and rows so insert a new one
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allvalues = {}
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allvalues.update(keyvalues)
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allvalues.update(values)
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sql = "INSERT INTO %s (%s) VALUES (%s)" % (
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table,
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", ".join(k for k in allvalues),
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", ".join("?" for _ in allvalues)
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)
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logger.debug(
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"[SQL] %s Args=%s",
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sql, keyvalues.values(),
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)
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txn.execute(sql, allvalues.values())
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def _simple_select_one(self, table, keyvalues, retcols,
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allow_none=False):
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"""Executes a SELECT query on the named table, which is expected to
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return a single row, returning a single column from it.
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Args:
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table : string giving the table name
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keyvalues : dict of column names and values to select the row with
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retcols : list of strings giving the names of the columns to return
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allow_none : If true, return None instead of failing if the SELECT
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statement returns no rows
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"""
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return self._simple_selectupdate_one(
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table, keyvalues, retcols=retcols, allow_none=allow_none
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)
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def _simple_select_one_onecol(self, table, keyvalues, retcol,
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allow_none=False):
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"""Executes a SELECT query on the named table, which is expected to
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return a single row, returning a single column from it."
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Args:
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table : string giving the table name
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keyvalues : dict of column names and values to select the row with
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retcol : string giving the name of the column to return
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"""
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return self.runInteraction(
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"_simple_select_one_onecol",
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self._simple_select_one_onecol_txn,
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table, keyvalues, retcol, allow_none=allow_none,
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)
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def _simple_select_one_onecol_txn(self, txn, table, keyvalues, retcol,
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allow_none=False):
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ret = self._simple_select_onecol_txn(
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txn,
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table=table,
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keyvalues=keyvalues,
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retcol=retcol,
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)
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if ret:
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return ret[0]
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else:
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if allow_none:
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return None
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else:
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raise StoreError(404, "No row found")
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def _simple_select_onecol_txn(self, txn, table, keyvalues, retcol):
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sql = (
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"SELECT %(retcol)s FROM %(table)s WHERE %(where)s "
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"ORDER BY rowid asc"
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) % {
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"retcol": retcol,
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"table": table,
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"where": " AND ".join("%s = ?" % k for k in keyvalues.keys()),
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}
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txn.execute(sql, keyvalues.values())
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return [r[0] for r in txn.fetchall()]
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def _simple_select_onecol(self, table, keyvalues, retcol):
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"""Executes a SELECT query on the named table, which returns a list
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comprising of the values of the named column from the selected rows.
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Args:
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table (str): table name
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keyvalues (dict): column names and values to select the rows with
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retcol (str): column whos value we wish to retrieve.
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Returns:
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Deferred: Results in a list
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"""
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return self.runInteraction(
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"_simple_select_onecol",
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self._simple_select_onecol_txn,
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table, keyvalues, retcol
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)
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def _simple_select_list(self, table, keyvalues, retcols):
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"""Executes a SELECT query on the named table, which may return zero or
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more rows, returning the result as a list of dicts.
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Args:
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table : string giving the table name
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keyvalues : dict of column names and values to select the rows with
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retcols : list of strings giving the names of the columns to return
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"""
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return self.runInteraction(
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"_simple_select_list",
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self._simple_select_list_txn,
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table, keyvalues, retcols
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)
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def _simple_select_list_txn(self, txn, table, keyvalues, retcols):
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"""Executes a SELECT query on the named table, which may return zero or
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more rows, returning the result as a list of dicts.
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Args:
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txn : Transaction object
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table : string giving the table name
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keyvalues : dict of column names and values to select the rows with
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retcols : list of strings giving the names of the columns to return
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"""
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sql = "SELECT %s FROM %s WHERE %s ORDER BY rowid asc" % (
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", ".join(retcols),
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table,
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" AND ".join("%s = ?" % (k, ) for k in keyvalues)
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)
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txn.execute(sql, keyvalues.values())
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return self.cursor_to_dict(txn)
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def _simple_update_one(self, table, keyvalues, updatevalues,
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retcols=None):
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"""Executes an UPDATE query on the named table, setting new values for
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columns in a row matching the key values.
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Args:
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table : string giving the table name
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keyvalues : dict of column names and values to select the row with
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updatevalues : dict giving column names and values to update
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retcols : optional list of column names to return
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If present, retcols gives a list of column names on which to perform
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a SELECT statement *before* performing the UPDATE statement. The values
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of these will be returned in a dict.
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These are performed within the same transaction, allowing an atomic
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get-and-set. This can be used to implement compare-and-set by putting
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the update column in the 'keyvalues' dict as well.
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"""
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return self._simple_selectupdate_one(table, keyvalues, updatevalues,
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retcols=retcols)
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def _simple_selectupdate_one(self, table, keyvalues, updatevalues=None,
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retcols=None, allow_none=False):
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""" Combined SELECT then UPDATE."""
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if retcols:
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select_sql = "SELECT %s FROM %s WHERE %s ORDER BY rowid asc" % (
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", ".join(retcols),
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table,
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" AND ".join("%s = ?" % (k) for k in keyvalues)
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)
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if updatevalues:
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update_sql = "UPDATE %s SET %s WHERE %s" % (
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table,
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", ".join("%s = ?" % (k,) for k in updatevalues),
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" AND ".join("%s = ?" % (k,) for k in keyvalues)
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)
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def func(txn):
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ret = None
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if retcols:
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txn.execute(select_sql, keyvalues.values())
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row = txn.fetchone()
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if not row:
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if allow_none:
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return None
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raise StoreError(404, "No row found")
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if txn.rowcount > 1:
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raise StoreError(500, "More than one row matched")
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ret = dict(zip(retcols, row))
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if updatevalues:
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txn.execute(
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update_sql,
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updatevalues.values() + keyvalues.values()
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)
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if txn.rowcount == 0:
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raise StoreError(404, "No row found")
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if txn.rowcount > 1:
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raise StoreError(500, "More than one row matched")
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return ret
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return self.runInteraction("_simple_selectupdate_one", func)
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def _simple_delete_one(self, table, keyvalues):
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"""Executes a DELETE query on the named table, expecting to delete a
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single row.
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Args:
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table : string giving the table name
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keyvalues : dict of column names and values to select the row with
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"""
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sql = "DELETE FROM %s WHERE %s" % (
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table,
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" AND ".join("%s = ?" % (k, ) for k in keyvalues)
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)
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def func(txn):
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txn.execute(sql, keyvalues.values())
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if txn.rowcount == 0:
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raise StoreError(404, "No row found")
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if txn.rowcount > 1:
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raise StoreError(500, "more than one row matched")
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return self.runInteraction("_simple_delete_one", func)
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def _simple_delete(self, table, keyvalues):
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"""Executes a DELETE query on the named table.
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Args:
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table : string giving the table name
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keyvalues : dict of column names and values to select the row with
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"""
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return self.runInteraction("_simple_delete", self._simple_delete_txn)
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def _simple_delete_txn(self, txn, table, keyvalues):
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sql = "DELETE FROM %s WHERE %s" % (
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table,
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" AND ".join("%s = ?" % (k, ) for k in keyvalues)
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)
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return txn.execute(sql, keyvalues.values())
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def _simple_max_id(self, table):
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"""Executes a SELECT query on the named table, expecting to return the
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max value for the column "id".
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Args:
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table : string giving the table name
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"""
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sql = "SELECT MAX(id) AS id FROM %s" % table
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def func(txn):
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txn.execute(sql)
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max_id = self.cursor_to_dict(txn)[0]["id"]
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if max_id is None:
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return 0
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return max_id
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|
return self.runInteraction("_simple_max_id", func)
|
|
|
|
def _get_events(self, event_ids, check_redacted=True,
|
|
get_prev_content=False):
|
|
return self.runInteraction(
|
|
"_get_events", self._get_events_txn, event_ids,
|
|
check_redacted=check_redacted, get_prev_content=get_prev_content,
|
|
)
|
|
|
|
def _get_events_txn(self, txn, event_ids, check_redacted=True,
|
|
get_prev_content=False):
|
|
if not event_ids:
|
|
return []
|
|
|
|
events = [
|
|
self._get_event_txn(
|
|
txn, event_id,
|
|
check_redacted=check_redacted,
|
|
get_prev_content=get_prev_content
|
|
)
|
|
for event_id in event_ids
|
|
]
|
|
|
|
return [e for e in events if e]
|
|
|
|
def _get_event_txn(self, txn, event_id, check_redacted=True,
|
|
get_prev_content=False, allow_rejected=False):
|
|
sql = (
|
|
"SELECT e.internal_metadata, e.json, r.event_id, rej.reason "
|
|
"FROM event_json as e "
|
|
"LEFT JOIN redactions as r ON e.event_id = r.redacts "
|
|
"LEFT JOIN rejections as rej on rej.event_id = e.event_id "
|
|
"WHERE e.event_id = ? "
|
|
"LIMIT 1 "
|
|
)
|
|
|
|
txn.execute(sql, (event_id,))
|
|
|
|
res = txn.fetchone()
|
|
|
|
if not res:
|
|
return None
|
|
|
|
internal_metadata, js, redacted, rejected_reason = res
|
|
|
|
if allow_rejected or not rejected_reason:
|
|
return self._get_event_from_row_txn(
|
|
txn, internal_metadata, js, redacted,
|
|
check_redacted=check_redacted,
|
|
get_prev_content=get_prev_content,
|
|
)
|
|
else:
|
|
return None
|
|
|
|
def _get_event_from_row_txn(self, txn, internal_metadata, js, redacted,
|
|
check_redacted=True, get_prev_content=False):
|
|
d = json.loads(js)
|
|
internal_metadata = json.loads(internal_metadata)
|
|
|
|
ev = FrozenEvent(d, internal_metadata_dict=internal_metadata)
|
|
|
|
if check_redacted and redacted:
|
|
ev = prune_event(ev)
|
|
|
|
ev.unsigned["redacted_by"] = redacted
|
|
# Get the redaction event.
|
|
|
|
because = self._get_event_txn(
|
|
txn,
|
|
redacted,
|
|
check_redacted=False
|
|
)
|
|
|
|
if because:
|
|
ev.unsigned["redacted_because"] = because
|
|
|
|
if get_prev_content and "replaces_state" in ev.unsigned:
|
|
prev = self._get_event_txn(
|
|
txn,
|
|
ev.unsigned["replaces_state"],
|
|
get_prev_content=False,
|
|
)
|
|
if prev:
|
|
ev.unsigned["prev_content"] = prev.get_dict()["content"]
|
|
|
|
return ev
|
|
|
|
def _parse_events(self, rows):
|
|
return self.runInteraction(
|
|
"_parse_events", self._parse_events_txn, rows
|
|
)
|
|
|
|
def _parse_events_txn(self, txn, rows):
|
|
event_ids = [r["event_id"] for r in rows]
|
|
|
|
return self._get_events_txn(txn, event_ids)
|
|
|
|
def _has_been_redacted_txn(self, txn, event):
|
|
sql = "SELECT event_id FROM redactions WHERE redacts = ?"
|
|
txn.execute(sql, (event.event_id,))
|
|
result = txn.fetchone()
|
|
return result[0] if result else None
|
|
|
|
|
|
class Table(object):
|
|
""" A base class used to store information about a particular table.
|
|
"""
|
|
|
|
table_name = None
|
|
""" str: The name of the table """
|
|
|
|
fields = None
|
|
""" list: The field names """
|
|
|
|
EntryType = None
|
|
""" Type: A tuple type used to decode the results """
|
|
|
|
_select_where_clause = "SELECT %s FROM %s WHERE %s"
|
|
_select_clause = "SELECT %s FROM %s"
|
|
_insert_clause = "INSERT OR REPLACE INTO %s (%s) VALUES (%s)"
|
|
|
|
@classmethod
|
|
def select_statement(cls, where_clause=None):
|
|
"""
|
|
Args:
|
|
where_clause (str): The WHERE clause to use.
|
|
|
|
Returns:
|
|
str: An SQL statement to select rows from the table with the given
|
|
WHERE clause.
|
|
"""
|
|
if where_clause:
|
|
return cls._select_where_clause % (
|
|
", ".join(cls.fields),
|
|
cls.table_name,
|
|
where_clause
|
|
)
|
|
else:
|
|
return cls._select_clause % (
|
|
", ".join(cls.fields),
|
|
cls.table_name,
|
|
)
|
|
|
|
@classmethod
|
|
def insert_statement(cls):
|
|
return cls._insert_clause % (
|
|
cls.table_name,
|
|
", ".join(cls.fields),
|
|
", ".join(["?"] * len(cls.fields)),
|
|
)
|
|
|
|
@classmethod
|
|
def decode_single_result(cls, results):
|
|
""" Given an iterable of tuples, return a single instance of
|
|
`EntryType` or None if the iterable is empty
|
|
Args:
|
|
results (list): The results list to convert to `EntryType`
|
|
Returns:
|
|
EntryType: An instance of `EntryType`
|
|
"""
|
|
results = list(results)
|
|
if results:
|
|
return cls.EntryType(*results[0])
|
|
else:
|
|
return None
|
|
|
|
@classmethod
|
|
def decode_results(cls, results):
|
|
""" Given an iterable of tuples, return a list of `EntryType`
|
|
Args:
|
|
results (list): The results list to convert to `EntryType`
|
|
|
|
Returns:
|
|
list: A list of `EntryType`
|
|
"""
|
|
return [cls.EntryType(*row) for row in results]
|
|
|
|
@classmethod
|
|
def get_fields_string(cls, prefix=None):
|
|
if prefix:
|
|
to_join = ("%s.%s" % (prefix, f) for f in cls.fields)
|
|
else:
|
|
to_join = cls.fields
|
|
|
|
return ", ".join(to_join)
|
|
|
|
|
|
class JoinHelper(object):
|
|
""" Used to help do joins on tables by looking at the tables' fields and
|
|
creating a list of unique fields to use with SELECTs and a namedtuple
|
|
to dump the results into.
|
|
|
|
Attributes:
|
|
tables (list): List of `Table` classes
|
|
EntryType (type)
|
|
"""
|
|
|
|
def __init__(self, *tables):
|
|
self.tables = tables
|
|
|
|
res = []
|
|
for table in self.tables:
|
|
res += [f for f in table.fields if f not in res]
|
|
|
|
self.EntryType = collections.namedtuple("JoinHelperEntry", res)
|
|
|
|
def get_fields(self, **prefixes):
|
|
"""Get a string representing a list of fields for use in SELECT
|
|
statements with the given prefixes applied to each.
|
|
|
|
For example::
|
|
|
|
JoinHelper(PdusTable, StateTable).get_fields(
|
|
PdusTable="pdus",
|
|
StateTable="state"
|
|
)
|
|
"""
|
|
res = []
|
|
for field in self.EntryType._fields:
|
|
for table in self.tables:
|
|
if field in table.fields:
|
|
res.append("%s.%s" % (prefixes[table.__name__], field))
|
|
break
|
|
|
|
return ", ".join(res)
|
|
|
|
def decode_results(self, rows):
|
|
return [self.EntryType(*row) for row in rows]
|