wrw/util.py

   1 import inspect, math
   2 import req, dispatch, session, form, resp, proto
   3
   4 def wsgiwrap(callable):
   5     def wrapper(env, startreq):
   6         return dispatch.handleenv(env, startreq, callable)
   7     wrapper.__wrapped__ = callable
   8     return wrapper
   9
  10 def formparams(callable):
  11     spec = inspect.getargspec(callable)
  12     def wrapper(req):
  13         data = form.formdata(req)
  14         args = dict(data.items())
  15         args["req"] = req
  16         if not spec.keywords:
  17             for arg in list(args):
  18                 if arg not in spec.args:
  19                     del args[arg]
  20         for i in xrange(len(spec.args) - (len(spec.defaults) if spec.defaults else 0)):
  21             if spec.args[i] not in args:
  22                 raise resp.httperror(400, "Missing parameter", ("The query parameter `", resp.h.code(spec.args[i]), "' is required but not supplied."))
  23         return callable(**args)
  24     wrapper.__wrapped__ = callable
  25     return wrapper
  26
  27 class funplex(object):
  28     def __init__(self, *funs, **nfuns):
  29         self.dir = {}
  30         self.dir.update(((self.unwrap(fun).__name__, fun) for fun in funs))
  31         self.dir.update(nfuns)
  32
  33     @staticmethod
  34     def unwrap(fun):
  35         while hasattr(fun, "__wrapped__"):
  36             fun = fun.__wrapped__
  37         return fun
  38
  39     def __call__(self, req):
  40         if req.pathinfo == "":
  41             raise resp.redirect(req.uriname + "/")
  42         if req.pathinfo[:1] != "/":
  43             raise resp.notfound()
  44         p = req.pathinfo[1:]
  45         if p == "":
  46             p = "__index__"
  47             bi = 1
  48         else:
  49             p = p.partition("/")[0]
  50             bi = len(p) + 1
  51         if p in self.dir:
  52             sreq = req.shift(bi)
  53             sreq.selfpath = req.pathinfo[1:]
  54             return self.dir[p](sreq)
  55         raise resp.notfound()
  56
  57     def add(self, fun):
  58         self.dir[self.unwrap(fun).__name__] = fun
  59         return fun
  60
  61     def name(self, name):
  62         def dec(fun):
  63             self.dir[name] = fun
  64             return fun
  65         return dec
  66
  67 def persession(data=None):
  68     def dec(callable):
  69         def wrapper(req):
  70             sess = session.get(req)
  71             if callable not in sess:
  72                 if data is None:
  73                     sess[callable] = callable()
  74                 else:
  75                     if data not in sess:
  76                         sess[data] = data()
  77                     sess[callable] = callable(data)
  78             return sess[callable].handle(req)
  79         wrapper.__wrapped__ = callable
  80         return wrapper
  81     return dec
  82
  83 class preiter(object):
  84     __slots__ = ["bk", "bki", "_next"]
  85     end = object()
  86     def __init__(self, real):
  87         self.bk = real
  88         self.bki = iter(real)
  89         self._next = None
  90         self.next()
  91
  92     def __iter__(self):
  93         return self
  94
  95     def next(self):
  96         if self._next is self.end:
  97             raise StopIteration()
  98         ret = self._next
  99         try:
 100             self._next = next(self.bki)
 101         except StopIteration:
 102             self._next = self.end
 103         return ret
 104
 105     def close(self):
 106         if hasattr(self.bk, "close"):
 107             self.bk.close()
 108
 109 def pregen(callable):
 110     def wrapper(*args, **kwargs):
 111         return preiter(callable(*args, **kwargs))
 112     wrapper.__wrapped__ = callable
 113     return wrapper
 114
 115 class sessiondata(object):
 116     @classmethod
 117     def get(cls, req, create=True):
 118         sess = cls.sessdb().get(req)
 119         with sess.lock:
 120             try:
 121                 return sess[cls]
 122             except KeyError:
 123                 if not create:
 124                     return None
 125                 ret = cls(req, sess)
 126                 sess[cls] = ret
 127                 return ret
 128
 129     @classmethod
 130     def sessdb(cls):
 131         return session.default.val
 132
 133 class autodirty(sessiondata):
 134     @classmethod
 135     def get(cls, req):
 136         ret = super(autodirty, cls).get(req)
 137         if "_is_dirty" not in ret.__dict__:
 138             ret.__dict__["_is_dirty"] = False
 139         return ret
 140
 141     def sessfrozen(self):
 142         self.__dict__["_is_dirty"] = False
 143
 144     def sessdirty(self):
 145         return self._is_dirty
 146
 147     def __setattr__(self, name, value):
 148         super(autodirty, self).__setattr__(name, value)
 149         if "_is_dirty" in self.__dict__:
 150             self.__dict__["_is_dirty"] = True
 151
 152     def __delattr__(self, name):
 153         super(autodirty, self).__delattr__(name, value)
 154         if "_is_dirty" in self.__dict__:
 155             self.__dict__["_is_dirty"] = True
 156
 157 class manudirty(object):
 158     def __init__(self, *args, **kwargs):
 159         super(manudirty, self).__init__(*args, **kwargs)
 160         self.__dirty = False
 161
 162     def sessfrozen(self):
 163         self.__dirty = False
 164
 165     def sessdirty(self):
 166         return self.__dirty
 167
 168     def dirty(self):
 169         self.__dirty = True
 170
 171 class specslot(object):
 172     __slots__ = ["nm", "idx", "dirty"]
 173     unbound = object()
 174
 175     def __init__(self, nm, idx, dirty):
 176         self.nm = nm
 177         self.idx = idx
 178         self.dirty = dirty
 179
 180     @staticmethod
 181     def slist(ins):
 182         # Avoid calling __getattribute__
 183         return specdirty.__sslots__.__get__(ins, type(ins))
 184
 185     def __get__(self, ins, cls):
 186         val = self.slist(ins)[self.idx]
 187         if val is specslot.unbound:
 188             raise AttributeError("specslot %r is unbound" % self.nm)
 189         return val
 190
 191     def __set__(self, ins, val):
 192         self.slist(ins)[self.idx] = val
 193         if self.dirty:
 194             ins.dirty()
 195
 196     def __delete__(self, ins):
 197         self.slist(ins)[self.idx] = specslot.unbound
 198         ins.dirty()
 199
 200 class specclass(type):
 201     def __init__(self, name, bases, tdict):
 202         super(specclass, self).__init__(name, bases, tdict)
 203         sslots = set()
 204         dslots = set()
 205         for cls in self.__mro__:
 206             css = cls.__dict__.get("__saveslots__", ())
 207             sslots.update(css)
 208             dslots.update(cls.__dict__.get("__dirtyslots__", css))
 209         self.__sslots_l__ = list(sslots)
 210         self.__sslots_a__ = list(sslots | dslots)
 211         for i, slot in enumerate(self.__sslots_a__):
 212             setattr(self, slot, specslot(slot, i, slot in dslots))
 213
 214 class specdirty(sessiondata):
 215     __metaclass__ = specclass
 216     __slots__ = ["session", "__sslots__", "_is_dirty"]
 217
 218     def __specinit__(self):
 219         pass
 220
 221     @staticmethod
 222     def __new__(cls, req, sess):
 223         self = super(specdirty, cls).__new__(cls)
 224         self.session = sess
 225         self.__sslots__ = [specslot.unbound] * len(cls.__sslots_a__)
 226         self.__specinit__()
 227         self._is_dirty = False
 228         return self
 229
 230     def __getnewargs__(self):
 231         return (None, self.session)
 232
 233     def dirty(self):
 234         self._is_dirty = True
 235
 236     def sessfrozen(self):
 237         self._is_dirty = False
 238
 239     def sessdirty(self):
 240         return self._is_dirty
 241
 242     def __getstate__(self):
 243         ret = {}
 244         for nm, val in zip(type(self).__sslots_a__, specslot.slist(self)):
 245             if val is specslot.unbound:
 246                 ret[nm] = False, None
 247             else:
 248                 ret[nm] = True, val
 249         return ret
 250
 251     def __setstate__(self, st):
 252         ss = specslot.slist(self)
 253         for i, nm in enumerate(type(self).__sslots_a__):
 254             bound, val = st.pop(nm, (False, None))
 255             if not bound:
 256                 ss[i] = specslot.unbound
 257             else:
 258                 ss[i] = val
 259
 260 def datecheck(req, mtime):
 261     if "If-Modified-Since" in req.ihead:
 262         rtime = proto.phttpdate(req.ihead["If-Modified-Since"])
 263         if rtime is not None and rtime >= math.floor(mtime):
 264             raise resp.unmodified()
 265     req.ohead["Last-Modified"] = proto.httpdate(mtime)