|
| 1 | +import time |
| 2 | +from os import getenv |
| 3 | + |
| 4 | +import psycopg2 |
| 5 | +from psycopg2 import OperationalError, DatabaseError, InterfaceError |
| 6 | +from psycopg2.extras import DictCursor |
| 7 | +import logging |
| 8 | + |
| 9 | +TIMEOUT = int(getenv("SQL_STATEMENT_TIMEOUT", 0)) |
| 10 | +RETRY = int(getenv("SQL_STATEMENT_RETRY_ATTEMPTS", 3)) |
| 11 | +DELAY = int(getenv("SQL_DELAY_BETWEEN_STATEMENTS", 30)) |
| 12 | + |
| 13 | + |
| 14 | +def database_retry_decorator(func): |
| 15 | + def wrapper(self, *args, **kwargs): |
| 16 | + attempt = 1 |
| 17 | + while attempt <= RETRY: |
| 18 | + try: |
| 19 | + self.ensure_connection() |
| 20 | + yield from func(self, *args, **kwargs) |
| 21 | + return |
| 22 | + |
| 23 | + except (OperationalError, DatabaseError, InterfaceError) as e: |
| 24 | + if attempt >= RETRY: |
| 25 | + self.logger.error(f"Query failed after {RETRY} attempts: {str(e).rstrip()}") |
| 26 | + return |
| 27 | + |
| 28 | + self.logger.error( |
| 29 | + f"Attempt {attempt}/{RETRY} failed ({str(e).rstrip()}), retrying in {DELAY} seconds" |
| 30 | + ) |
| 31 | + time.sleep(DELAY) |
| 32 | + attempt += 1 |
| 33 | + try: |
| 34 | + if self._connection: |
| 35 | + self._connection.rollback() |
| 36 | + except Exception as e: |
| 37 | + self.logger.error(f"Connection rollback failed {str(e).rstrip()}") |
| 38 | + return |
| 39 | + |
| 40 | + return wrapper |
| 41 | + |
| 42 | + |
| 43 | +class DatabaseManager: |
| 44 | + def __init__(self, db_configs, logger): |
| 45 | + self.logger = logger |
| 46 | + self._work_db_config = db_configs |
| 47 | + self._connection = self.connect_working_db() |
| 48 | + |
| 49 | + def connect_working_db(self): |
| 50 | + """ |
| 51 | + Fonction de connexion à la BDD de travail |
| 52 | +
|
| 53 | + Parameters |
| 54 | + ---------- |
| 55 | + config: dict |
| 56 | + dictionnaire correspondant à la configuration décrite dans le fichier passé en argument |
| 57 | + db_configs: dict |
| 58 | + dictionnaire correspondant aux configurations des bdd |
| 59 | + Returns |
| 60 | + ------- |
| 61 | + connection: psycopg2.connection |
| 62 | + connection à la bdd de travail |
| 63 | +
|
| 64 | + """ |
| 65 | + # Récupération des paramètres de la bdd |
| 66 | + host = self._work_db_config.get("host") |
| 67 | + dbname = self._work_db_config.get("database") |
| 68 | + user = self._work_db_config.get("user") |
| 69 | + password = self._work_db_config.get("password") |
| 70 | + port = self._work_db_config.get("port") |
| 71 | + connect_args = "host=%s dbname=%s user=%s password=%s port=%s" % (host, dbname, user, password, port) |
| 72 | + |
| 73 | + self.logger.info("Connecting to work database") |
| 74 | + connection = psycopg2.connect(connect_args) |
| 75 | + connection.set_client_encoding("UTF8") |
| 76 | + |
| 77 | + return connection |
| 78 | + |
| 79 | + def disconnect_working_db(self): |
| 80 | + """ |
| 81 | + Fonction de connexion à la BDD de travail |
| 82 | +
|
| 83 | + Parameters |
| 84 | + ---------- |
| 85 | + connection: psycopg2.connection |
| 86 | + connection à la bdd de travail |
| 87 | + logger: logging.Logger |
| 88 | + """ |
| 89 | + if self._connection: |
| 90 | + self._connection.close() |
| 91 | + self.logger.info("Connection to work database closed") |
| 92 | + |
| 93 | + def ensure_connection(self): |
| 94 | + """ |
| 95 | + Ensure the connection is alive; reconnect if needed. |
| 96 | + """ |
| 97 | + try: |
| 98 | + if self._connection is None or getattr(self._connection, "closed", 1) != 0: |
| 99 | + self.logger.info("Connection is closed or missing; reconnecting") |
| 100 | + self._connection = self.connect_working_db() |
| 101 | + else: |
| 102 | + with self._connection.cursor() as cur: |
| 103 | + cur.execute("SELECT 1") |
| 104 | + except Exception as e: |
| 105 | + self.logger.error( |
| 106 | + f"Something is wrong with the connection: {str(e).rstrip()}; reconnecting in {DELAY} seconds") |
| 107 | + self.disconnect_working_db() |
| 108 | + time.sleep(DELAY) |
| 109 | + self._connection = self.connect_working_db() |
| 110 | + |
| 111 | + def execute_select_query(self, cursor, query, show_duration): |
| 112 | + if TIMEOUT: |
| 113 | + cursor.execute("SET statement_timeout = %s", (1000 * TIMEOUT,)) # timeout in milliseconds |
| 114 | + |
| 115 | + if show_duration: |
| 116 | + self.logger.info("SQL: {}".format(query)) |
| 117 | + st_execute = time.time() |
| 118 | + cursor.execute(query) |
| 119 | + et_execute = time.time() |
| 120 | + self.logger.info("Execution ended. Elapsed time : %s seconds." % (et_execute - st_execute)) |
| 121 | + else: |
| 122 | + cursor.execute(query) |
| 123 | + |
| 124 | + @database_retry_decorator |
| 125 | + def execute_select_fetch_multiple(self, query, batchsize=1, show_duration=False): |
| 126 | + with self._connection.cursor(cursor_factory=DictCursor) as cursor: |
| 127 | + self.execute_select_query(cursor, query, show_duration) |
| 128 | + rows = cursor.fetchmany(batchsize) |
| 129 | + count = cursor.rowcount |
| 130 | + while rows: |
| 131 | + if batchsize == 1: |
| 132 | + rows = rows.pop() |
| 133 | + yield rows, count |
| 134 | + rows = cursor.fetchmany(batchsize) |
| 135 | + self._connection.commit() |
| 136 | + return |
| 137 | + |
| 138 | + # the method below should be used as a generator function otherwise use execute_update |
| 139 | + @database_retry_decorator |
| 140 | + def execute_update_query(self, query, params=None, isolation_level=None): |
| 141 | + self.logger.info("SQL: {}".format(query)) |
| 142 | + st_execute = time.time() |
| 143 | + with self._connection.cursor(cursor_factory=DictCursor) as cursor: |
| 144 | + old_isolation_level = self._connection.isolation_level |
| 145 | + if isolation_level is not None: |
| 146 | + self._connection.set_isolation_level(isolation_level) |
| 147 | + cursor.execute(query, params) |
| 148 | + et_execute = time.time() |
| 149 | + self.logger.info("Execution ended. Elapsed time : %s seconds." % (et_execute - st_execute)) |
| 150 | + self._connection.set_isolation_level(old_isolation_level) |
| 151 | + self._connection.commit() |
| 152 | + yield # the decorator database_retry_decorator only supports generators |
| 153 | + return |
| 154 | + |
| 155 | + def execute_update(self, query, params=None, isolation_level=None): |
| 156 | + next(self.execute_update_query(query, params=params, isolation_level=isolation_level), None) |
| 157 | + |
| 158 | + def execute_select_fetch_one(self, query, show_duration=False): |
| 159 | + gen = self.execute_select_fetch_multiple(query, 1, show_duration) |
| 160 | + row, count = next(gen, (None, None)) |
| 161 | + return row, count |
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