| 1 | import threading, pickle |
| 2 | from . import db, index, cache |
| 3 | from .db import txnfun |
| 4 | |
| 5 | class environment(object): |
| 6 | def __init__(self, path): |
| 7 | self.path = path |
| 8 | self.lk = threading.Lock() |
| 9 | self.bk = None |
| 10 | |
| 11 | def __call__(self): |
| 12 | with self.lk: |
| 13 | if self.bk is None: |
| 14 | self.bk = db.environment(self.path) |
| 15 | return self.bk |
| 16 | |
| 17 | def close(self): |
| 18 | with self.lk: |
| 19 | if self.bk is not None: |
| 20 | self.bk.close() |
| 21 | self.bk = None |
| 22 | |
| 23 | class storedesc(object): |
| 24 | pass |
| 25 | |
| 26 | def storedescs(obj): |
| 27 | t = type(obj) |
| 28 | ret = getattr(t, "__didex_attr", None) |
| 29 | if ret is None: |
| 30 | ret = [] |
| 31 | for nm, val in t.__dict__.items(): |
| 32 | if isinstance(val, storedesc): |
| 33 | ret.append((nm, val)) |
| 34 | t.__didex_attr = ret |
| 35 | return ret |
| 36 | |
| 37 | class store(object): |
| 38 | def __init__(self, name, *, env=None, path=".", ncache=None): |
| 39 | self.name = name |
| 40 | self.lk = threading.Lock() |
| 41 | if env: |
| 42 | self.env = env |
| 43 | else: |
| 44 | self.env = environment(path) |
| 45 | self._db = None |
| 46 | if ncache is None: |
| 47 | ncache = cache.cache() |
| 48 | self.cache = ncache |
| 49 | self.cache.load = self._load |
| 50 | |
| 51 | def db(self): |
| 52 | with self.lk: |
| 53 | if self._db is None: |
| 54 | self._db = self.env().db(self.name) |
| 55 | return self._db |
| 56 | |
| 57 | def _load(self, id): |
| 58 | try: |
| 59 | return pickle.loads(self.db().get(id)) |
| 60 | except: |
| 61 | raise KeyError(id, "could not unpickle data") |
| 62 | |
| 63 | def _encode(self, obj): |
| 64 | return pickle.dumps(obj) |
| 65 | |
| 66 | def get(self, id, *, load=True): |
| 67 | return self.cache.get(id, load=load) |
| 68 | |
| 69 | @txnfun(lambda self: self.db().env.env) |
| 70 | def register(self, obj, *, tx): |
| 71 | id = self.db().add(self._encode(obj), tx=tx) |
| 72 | for nm, attr in storedescs(obj): |
| 73 | attr.register(id, obj, tx) |
| 74 | self.cache.put(id, obj) |
| 75 | return id |
| 76 | |
| 77 | @txnfun(lambda self: self.db().env.env) |
| 78 | def unregister(self, id, *, tx): |
| 79 | obj = self.get(id) |
| 80 | for nm, attr in storedescs(obj): |
| 81 | attr.unregister(id, obj, tx) |
| 82 | self.db().remove(id, tx=tx) |
| 83 | self.cache.remove(id) |
| 84 | |
| 85 | @txnfun(lambda self: self.db().env.env) |
| 86 | def update(self, id, *, tx): |
| 87 | obj = self.get(id, load=False) |
| 88 | for nm, attr, in storedescs(obj): |
| 89 | attr.update(id, obj, tx) |
| 90 | self.db().replace(id, self._encode(obj), tx=tx) |