Commit | Line | Data |
---|---|---|
b080a59c FT |
1 | import threading, pickle |
2 | from . import db, index, cache | |
3 | from .db import txnfun | |
4 | ||
5 | class environment(object): | |
eca9b3be FT |
6 | def __init__(self, *, path=None, getpath=None, recover=False): |
7 | if path is not None: | |
8 | self.path = path | |
9 | self.getpath = None | |
10 | else: | |
11 | self.path = None | |
12 | self.getpath = getpath | |
13 | self.recover = recover | |
b080a59c FT |
14 | self.lk = threading.Lock() |
15 | self.bk = None | |
16 | ||
17 | def __call__(self): | |
18 | with self.lk: | |
19 | if self.bk is None: | |
eca9b3be FT |
20 | if self.path is None: |
21 | self.path = self.getpath() | |
22 | self.bk = db.environment(self.path, recover=self.recover) | |
b080a59c FT |
23 | return self.bk |
24 | ||
25 | def close(self): | |
26 | with self.lk: | |
27 | if self.bk is not None: | |
28 | self.bk.close() | |
29 | self.bk = None | |
30 | ||
31 | class storedesc(object): | |
32 | pass | |
33 | ||
34 | def storedescs(obj): | |
35 | t = type(obj) | |
36 | ret = getattr(t, "__didex_attr", None) | |
37 | if ret is None: | |
38 | ret = [] | |
39 | for nm, val in t.__dict__.items(): | |
40 | if isinstance(val, storedesc): | |
41 | ret.append((nm, val)) | |
42 | t.__didex_attr = ret | |
43 | return ret | |
44 | ||
45 | class store(object): | |
46 | def __init__(self, name, *, env=None, path=".", ncache=None): | |
47 | self.name = name | |
48 | self.lk = threading.Lock() | |
49 | if env: | |
50 | self.env = env | |
51 | else: | |
eca9b3be | 52 | self.env = environment(path=path) |
b080a59c FT |
53 | self._db = None |
54 | if ncache is None: | |
55 | ncache = cache.cache() | |
56 | self.cache = ncache | |
57 | self.cache.load = self._load | |
58 | ||
59 | def db(self): | |
60 | with self.lk: | |
61 | if self._db is None: | |
62 | self._db = self.env().db(self.name) | |
63 | return self._db | |
64 | ||
65 | def _load(self, id): | |
66 | try: | |
67 | return pickle.loads(self.db().get(id)) | |
68 | except: | |
69 | raise KeyError(id, "could not unpickle data") | |
70 | ||
71 | def _encode(self, obj): | |
72 | return pickle.dumps(obj) | |
73 | ||
74 | def get(self, id, *, load=True): | |
75 | return self.cache.get(id, load=load) | |
76 | ||
77 | @txnfun(lambda self: self.db().env.env) | |
78 | def register(self, obj, *, tx): | |
79 | id = self.db().add(self._encode(obj), tx=tx) | |
80 | for nm, attr in storedescs(obj): | |
81 | attr.register(id, obj, tx) | |
82 | self.cache.put(id, obj) | |
83 | return id | |
84 | ||
85 | @txnfun(lambda self: self.db().env.env) | |
ca180faa | 86 | def unregister(self, id, *, vfy=None, tx): |
b080a59c | 87 | obj = self.get(id) |
ca180faa FT |
88 | if vfy is not None and obj is not vfy: |
89 | raise RuntimeError("object identity crisis: " + str(vfy) + " is not cached object " + obj) | |
b080a59c FT |
90 | for nm, attr in storedescs(obj): |
91 | attr.unregister(id, obj, tx) | |
92 | self.db().remove(id, tx=tx) | |
93 | self.cache.remove(id) | |
94 | ||
95 | @txnfun(lambda self: self.db().env.env) | |
ca180faa | 96 | def update(self, id, *, vfy=None, tx): |
b080a59c | 97 | obj = self.get(id, load=False) |
ca180faa FT |
98 | if vfy is not None and obj is not vfy: |
99 | raise RuntimeError("object identity crisis: " + str(vfy) + " is not cached object " + obj) | |
b080a59c FT |
100 | for nm, attr, in storedescs(obj): |
101 | attr.update(id, obj, tx) | |
102 | self.db().replace(id, self._encode(obj), tx=tx) | |
ca180faa FT |
103 | |
104 | class autotype(type): | |
105 | def __call__(self, *args, **kwargs): | |
106 | new = super().__call__(*args, **kwargs) | |
107 | new.id = self.store.register(new) | |
108 | return new | |
109 | ||
110 | class autostore(object, metaclass=autotype): | |
111 | def __init__(self): | |
112 | self.id = None | |
113 | ||
114 | def save(self): | |
115 | self.store.update(self.id, vfy=self) | |
116 | ||
117 | def remove(self): | |
118 | self.store.unregister(self.id, vfy=self) | |
119 | self.id = None |