openerp/tools/cache.py

   1 import lru
   2
   3 class ormcache(object):
   4     """ LRU cache decorator for orm methods
   5     """
   6
   7     def __init__(self, skiparg=2, size=8192, multi=None, timeout=None):
   8         self.skiparg = skiparg
   9         self.size = size
  10         self.method = None
  11         self.stat_miss = 0
  12         self.stat_hit = 0
  13         self.stat_err = 0
  14
  15     def __call__(self,m):
  16         self.method = m
  17         def lookup(self2, cr, *args):
  18             r = self.lookup(self2, cr, *args)
  19             #self.stat()
  20             return r
  21         lookup.clear_cache = self.clear
  22         #print "lookup-func",lookup
  23         return lookup
  24
  25     def stat(self):
  26         print "lookup-stats hit=%s miss=%s err=%s ratio=%.1f" % (self.stat_hit,self.stat_miss,self.stat_err, (100*float(self.stat_hit))/(self.stat_miss+self.stat_hit) )
  27
  28     def lru(self, self2):
  29         try:
  30             ormcache = getattr(self2, '_ormcache')
  31         except AttributeError:
  32             ormcache = self2._ormcache = {}
  33         try:
  34             d = ormcache[self.method]
  35         except KeyError:
  36             d = ormcache[self.method] = lru.LRU(self.size)
  37         return d
  38
  39     def lookup(self, self2, cr, *args):
  40         d = self.lru(self2)
  41         key = args[self.skiparg-2:]
  42         try:
  43            r = d[key]
  44            #print "lookup-hit",self2,cr,key,r
  45            self.stat_hit += 1
  46            return r
  47         except KeyError:
  48            self.stat_miss += 1
  49            #print "lookup-miss",self2,cr,key
  50            value = d[args] = self.method(self2, cr, *args)
  51            #print "lookup-miss-value",value
  52            return value
  53         except TypeError:
  54            self.stat_err += 1
  55            #print "lookup-error",self2,cr,key
  56            return self.method(self2, cr, *args)
  57
  58     def clear(self, self2, *args):
  59         """ Remove *args entry from the cache or all keys if *args is undefined
  60         """
  61         d = self.lru(self2)
  62         if args:
  63             try:
  64                 key = args[self.skiparg-2:]
  65                 #print "del",key
  66                 del d[key]
  67             except KeyError:
  68                 pass
  69         else:
  70             d.clear()
  71
  72 class ormcache_multi(ormcache):
  73     def __init__(self, skiparg=2, size=8192, multi=3):
  74         super(ormcache_multi,self).__init__(skiparg,size)
  75         self.multi = multi - 2
  76
  77     def lookup(self, self2, cr, *args):
  78         d = self.lru(self2)
  79         args = list(args)
  80         multi = self.multi
  81         #print args, multi
  82         ids = args[multi]
  83         r = {}
  84         miss = []
  85
  86         for i in ids:
  87             args[multi] = i
  88             key = tuple(args[self.skiparg-2:])
  89             try:
  90                r[i] = d[key]
  91                #print "lookup-hit",self2,cr,key,r[i]
  92                self.stat_hit += 1
  93             except Exception:
  94                self.stat_miss += 1
  95                miss.append(i)
  96                #print "lookup-miss",self2,cr,key
  97
  98         if miss:
  99             args[multi] = miss
 100             r.update(self.method(self2, cr, *args))
 101
 102         for i in miss:
 103             args[multi] = i
 104             key = tuple(args[self.skiparg-2:])
 105             d[key] = r[i]
 106
 107         return r
 108
 109 class dummy_cache(object):
 110     """ Cache decorator replacement to actually do no caching.
 111     """
 112     def __init__(self, *l, **kw):
 113         pass
 114     def __call__(self, fn):
 115         fn.clear_cache = self.clear
 116         return fn
 117     def clear(self, *l, **kw):
 118         pass
 119
 120 #ormcache = dummy_cache
 121 cache = dummy_cache
 122
 123 if __name__ == '__main__':
 124
 125     class A():
 126         @ormcache()
 127         def m(self,a,b):
 128             print  "A::m(", self,a,b
 129             return 1
 130
 131         @ormcache_multi(multi=3)
 132         def n(self,cr,uid,ids):
 133             print  "m", self,cr,uid,ids
 134             return dict([(i,i) for i in ids])
 135
 136     a=A()
 137     #r=a.m(1,2)
 138     #r=a.m(1,2)
 139     r=a.n("cr",1,[1,2,3,4])
 140     r=a.n("cr",1,[1,2])
 141     print r
 142     for i in a._ormcache:
 143         print a._ormcache[i].d
 144     a.n.clear_cache(a,1,1)
 145     r=a.n("cr",1,[1,2])
 146     print r
 147     #r=a.n("cr",1,[1,2])