31 lines
1012 B
Python
31 lines
1012 B
Python
import sqlite3
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import time
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LOCKED_MSGS = ("database is locked", "database is busy")
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def connect(db_path, timeout=30):
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"""Open a SQLite connection hardened against cross-process contention.
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Enables WAL mode and a busy timeout so that the multiple bot processes
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sharing a database file wait for each other instead of raising
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``OperationalError: database is locked`` immediately.
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"""
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conn = sqlite3.connect(db_path, timeout=timeout)
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conn.execute("PRAGMA busy_timeout=%d" % (timeout * 1000))
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conn.execute("PRAGMA journal_mode=WAL")
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return conn
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def commit(conn, retries=5, backoff=0.2):
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"""Commit, retrying briefly when the database is locked by another writer."""
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for attempt in range(retries):
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try:
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conn.commit()
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return
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except sqlite3.OperationalError as e:
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if str(e).lower() in LOCKED_MSGS and attempt < retries - 1:
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time.sleep(backoff * (attempt + 1))
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continue
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raise |