|
- # -*- coding: utf-8 -*-
-
- from datetime import datetime
- import random
- import sqlite3
-
- from flask import g
- from werkzeug.local import LocalProxy
-
- __all__ = ["Database"]
-
- class Database:
- """Database manager for low-level authentication actions."""
- MAX_SESSION_STALENESS = 2 * 60 * 60 # 2 hours
- MAX_SESSION_AGE = 24 * 60 * 60 # 24 hours
- SESSION_GRACE = 60 * 60 # 1 hour
- path = None
-
- def __init__(self):
- if self.path is None:
- raise RuntimeError("Database.path not set")
- self._conn = sqlite3.connect(self.path)
-
- def __enter__(self):
- return self._conn.__enter__()
-
- def __exit__(self, exc_type, exc_value, trace):
- return self._conn.__exit__(exc_type, exc_value, trace)
-
- @classmethod
- def _get(cls):
- """Return the current database, or allocate a new one if necessary."""
- if not hasattr(g, "_db"):
- g._db = cls()
- return g._db
-
- @classmethod
- def pre_hook(cls):
- """Hook to be called before a request context.
-
- Sets up the g.db proxy.
- """
- g.db = LocalProxy(cls._get)
-
- @classmethod
- def post_hook(cls, exc):
- """Hook to be called when tearing down an application context.
-
- Closes the database if necessary.
- """
- if hasattr(g, "_db"):
- g._db.close()
-
- def close(self):
- """Close the database connection."""
- return self._conn.close()
-
- def _clear_old_sessions(self):
- """Remove old sessions from the database.
-
- Sessions can expire if they are not touched (accessed) in a certain
- period of time, or if their absolute age exceeds some number. We don't
- actually remove them until a bit after this time.
- """
- query = """DELETE FROM session WHERE
- strftime("%s", "now") - strftime("%s", session_created) >= {} OR
- strftime("%s", "now") - strftime("%s", session_touched) >= {}"""
- create_thresh = self.MAX_SESSION_AGE + self.SESSION_GRACE
- touch_thresh = self.MAX_SESSION_STALENESS + self.SESSION_GRACE
-
- with self._conn as conn:
- conn.execute(query.format(create_thresh, touch_thresh))
-
- def new_session(self):
- """Allocate a new session in the database.
-
- Return its ID as an integer and creation timestamp as a naive UTC
- datetime.
- """
- created = datetime.utcnow().replace(microsecond=0)
- query = "INSERT INTO session (session_created) VALUES (?)"
- with self._conn as conn:
- cur = conn.execute(query, (created,))
- return cur.lastrowid, created
-
- def has_session(self, sid):
- """Return the creation timestamp for the given session ID, or None.
-
- Will only return a timestamp for non-expired sessions. This function
- randomly does database maintenance; very old expired sessions may be
- cleared.
- """
- if random.random() <= 0.2:
- self._clear_old_sessions()
-
- query = """SELECT session_created FROM session
- WHERE session_id = ? AND
- strftime("%s", "now") - strftime("%s", session_created) < {} AND
- strftime("%s", "now") - strftime("%s", session_touched) < {}"""
- query = query.format(self.MAX_SESSION_AGE, self.MAX_SESSION_STALENESS)
-
- res = self._conn.execute(query, (sid,)).fetchall()
- if not res:
- return None
- return datetime.strptime(res[0][0], "%Y-%m-%d %H:%M:%S")
-
- def read_session(self, sid):
- """Return the character associated with the given session, or None."""
- query = """SELECT session_character FROM session
- WHERE session_id = ? AND
- strftime("%s", "now") - strftime("%s", session_created) < {} AND
- strftime("%s", "now") - strftime("%s", session_touched) < {}"""
- query = query.format(self.MAX_SESSION_AGE, self.MAX_SESSION_STALENESS)
-
- res = self._conn.execute(query, (sid,)).fetchall()
- return res[0][0] if res else None
-
- def touch_session(self, sid):
- """Update the given session's last access timestamp."""
- query = """UPDATE session
- SET session_touched = CURRENT_TIMESTAMP
- WHERE session_id = ?"""
-
- with self._conn as conn:
- conn.execute(query, (sid,))
-
- def attach_session(self, sid, cid):
- """Attach the given session to a character. Does not touch it."""
- query = """UPDATE session
- SET session_character = ?
- WHERE session_id = ?"""
-
- with self._conn as conn:
- conn.execute(query, (cid, sid))
-
- def drop_session(self, sid):
- """Remove the given session from the database."""
- with self._conn as conn:
- conn.execute("DELETE FROM session WHERE session_id = ?", (sid,))
-
- def put_character(self, cid, name):
- """Put a character into the database if they don't already exist."""
- with self._conn as conn:
- cur = conn.execute("BEGIN TRANSACTION")
- cur.execute(
- """UPDATE character SET character_name = ?
- WHERE character_id = ?""", (name, cid))
- if cur.rowcount == 0:
- cur.execute(
- """INSERT INTO character (character_id, character_name)
- VALUES (?, ?)""", (cid, name))
-
- def read_character(self, cid):
- """Return a dictionary of properties for the given character."""
- query = """SELECT character_name, character_style
- FROM character WHERE character_id = ?"""
- res = self._conn.execute(query, (cid,)).fetchall()
- return {"name": res[0][0], "style": res[0][1]} if res else {}
-
- def update_character(self, cid, prop, value):
- """Update a property for the given character."""
- props = {"name": "character_name", "style": "character_style"}
- field = props[prop]
- with self._conn as conn:
- conn.execute("""UPDATE character SET {} = ?
- WHERE character_id = ?""".format(field), (value, cid))
-
- def set_auth(self, cid, token, expires, refresh):
- """Set the authentication info for the given character."""
- with self._conn as conn:
- conn.execute("""INSERT OR REPLACE INTO auth
- (auth_character, auth_token, auth_token_expiry, auth_refresh)
- VALUES (?, ?, ?, ?)""", (cid, token, expires, refresh))
-
- def update_auth(self, cid, token, expires, refresh):
- """Update the authentication info for the given character.
-
- Functionally equivalent to set_auth provided that the character has an
- existing auth entry, but is more efficient.
- """
- with self._conn as conn:
- conn.execute("""UPDATE auth
- SET auth_token = ?, auth_token_expiry = ?, auth_refresh = ?
- WHERE auth_character = ?""", (token, expires, refresh, cid))
-
- def get_auth(self, cid):
- """Return authentication info for the given character.
-
- Return a 3-tuple of (access_token, token_expiry, refresh_token), or
- None if there is no auth info.
- """
- query = """SELECT auth_token, auth_token_expiry, auth_refresh
- FROM auth WHERE auth_character = ?"""
- res = self._conn.execute(query, (cid,)).fetchall()
- if not res:
- return None
-
- token, expiry, refresh = res[0]
- expires = datetime.strptime(expiry, "%Y-%m-%d %H:%M:%S")
- return token, expires, refresh
-
- def drop_auth(self, cid):
- """Drop any authentication info for the given character."""
- with self._conn as conn:
- conn.execute("DELETE FROM auth WHERE auth_character = ?", (cid,))
-
- def set_character_modprop(self, cid, module, prop, value):
- """Add or update a character module property."""
- with self._conn as conn:
- conn.execute("""INSERT OR REPLACE INTO character_prop
- (cprop_character, cprop_module, cprop_key, cprop_value)
- VALUES (?, ?, ?, ?)""", (cid, module, prop, value))
-
- def get_character_modprop(self, cid, module, prop):
- """Return the value of a character module property, or None."""
- query = """SELECT cprop_value FROM character_prop
- WHERE cprop_character = ? AND cprop_module = ? AND cprop_key = ?"""
- res = self._conn.execute(query, (cid, module, prop)).fetchall()
- return res[0][0] if res else None
|