class PickleShareDB(collections.MutableMapping):
    """ The main 'connection' object for PickleShare database """
    def __init__(self,root):
        """ Return a db object that will manage the specied directory"""
        self.root = Path(root).expanduser().abspath()
        if not self.root.isdir():
            self.root.makedirs()
        # cache has { 'key' : (obj, orig_mod_time) }
        self.cache = {}


    def __getitem__(self,key):
        """ db['key'] reading """
        fil = self.root / key
        try:
            mtime = (fil.stat()[stat.ST_MTIME])
        except OSError:
            raise KeyError(key)

        if fil in self.cache and mtime == self.cache[fil][1]:
            return self.cache[fil][0]
        try:
            # The cached item has expired, need to read
            obj = pickle.loads(fil.open("rb").read())
        except:
            raise KeyError(key)

        self.cache[fil] = (obj,mtime)
        return obj

    def __setitem__(self,key,value):
        """ db['key'] = 5 """
        fil = self.root / key
        parent = fil.parent
        if parent and not parent.isdir():
            parent.makedirs()
        # We specify protocol 2, so that we can mostly go between Python 2
        # and Python 3. We can upgrade to protocol 3 when Python 2 is obsolete.
        pickled = pickle.dump(value,fil.open('wb'), protocol=2)
        try:
            self.cache[fil] = (value,fil.mtime)
        except OSError,e:
            if e.errno != 2:
                raise
Esempio n. 2
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class PickleShareDB(collections.MutableMapping):
    """ The main 'connection' object for PickleShare database """
    def __init__(self, root):
        """ Return a db object that will manage the specied directory"""
        self.root = Path(root).expanduser().abspath()
        if not self.root.isdir():
            self.root.makedirs()
        # cache has { 'key' : (obj, orig_mod_time) }
        self.cache = {}

    def __getitem__(self, key):
        """ db['key'] reading """
        fil = self.root / key
        try:
            mtime = (fil.stat()[stat.ST_MTIME])
        except OSError:
            raise KeyError(key)

        if fil in self.cache and mtime == self.cache[fil][1]:
            return self.cache[fil][0]
        try:
            # The cached item has expired, need to read
            obj = pickle.loads(fil.open("rb").read())
        except:
            raise KeyError(key)

        self.cache[fil] = (obj, mtime)
        return obj

    def __setitem__(self, key, value):
        """ db['key'] = 5 """
        fil = self.root / key
        parent = fil.parent
        if parent and not parent.isdir():
            parent.makedirs()
        # We specify protocol 2, so that we can mostly go between Python 2
        # and Python 3. We can upgrade to protocol 3 when Python 2 is obsolete.
        pickled = pickle.dump(value, fil.open('wb'), protocol=2)
        try:
            self.cache[fil] = (value, fil.mtime)
        except OSError, e:
            if e.errno != 2:
                raise
Esempio n. 3
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class PickleShareDB(UserDict.DictMixin):
    """ The main 'connection' object for PickleShare database """
    def __init__(self,root):
        """ Return a db object that will manage the specied directory"""
        self.root = Path(root).expanduser().abspath()
        if not self.root.isdir():
            self.root.makedirs()
        # cache has { 'key' : (obj, orig_mod_time) }
        self.cache = {}
        

    def __getitem__(self,key):
        """ db['key'] reading """
        fil = self.root / key
        try:
            mtime = (fil.stat()[stat.ST_MTIME])
        except OSError:
            raise KeyError(key)

        if fil in self.cache and mtime == self.cache[fil][1]:
            return self.cache[fil][0]
        try:
            # The cached item has expired, need to read
            obj = pickle.load(fil.open())
        except:
            raise KeyError(key)
            
        self.cache[fil] = (obj,mtime)
        return obj
    
    def __setitem__(self,key,value):
        """ db['key'] = 5 """
        fil = self.root / key
        parent = fil.parent
        if parent and not parent.isdir():
            parent.makedirs()
        pickled = pickle.dump(value,fil.open('w'))
        try:
            self.cache[fil] = (value,fil.mtime)
        except OSError,e:
            if e.errno != 2:
                raise
Esempio n. 4
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class PickleShareDB(UserDict.DictMixin):
    """ The main 'connection' object for PickleShare database """
    def __init__(self,root):
        """ Return a db object that will manage the specied directory"""
        self.root = Path(root).expanduser().abspath()
        if not self.root.isdir():
            self.root.makedirs()
        # cache has { 'key' : (obj, orig_mod_time) }
        self.cache = {}
        

    def __getitem__(self,key):
        """ db['key'] reading """
        fil = self.root / key
        try:
            mtime = (fil.stat()[stat.ST_MTIME])
        except OSError:
            raise KeyError(key)

        if fil in self.cache and mtime == self.cache[fil][1]:
            return self.cache[fil][0]
        try:
            # The cached item has expired, need to read
            obj = pickle.load(fil.open())
        except:
            raise KeyError(key)
            
        self.cache[fil] = (obj,mtime)
        return obj
    
    def __setitem__(self,key,value):
        """ db['key'] = 5 """
        fil = self.root / key
        parent = fil.parent
        if parent and not parent.isdir():
            parent.makedirs()
        pickled = pickle.dump(value,fil.open('w'))
        try:
            self.cache[fil] = (value,fil.mtime)
        except OSError,e:
            if e.errno != 2:
                raise
Esempio n. 5
0
class PickleShareDB(collections.MutableMapping):
    """ The main 'connection' object for PickleShare database """
    def __init__(self,root):
        """ Return a db object that will manage the specied directory"""
        self.root = Path(root).expanduser().abspath()
        if not self.root.isdir():
            self.root.makedirs()
        # cache has { 'key' : (obj, orig_mod_time) }
        self.cache = {}


    def __getitem__(self,key):
        """ db['key'] reading """
        fil = self.root / key
        try:
            mtime = (fil.stat()[stat.ST_MTIME])
        except OSError:
            raise KeyError(key)

        if fil in self.cache and mtime == self.cache[fil][1]:
            return self.cache[fil][0]
        try:
            # The cached item has expired, need to read
            with fil.open("rb") as f:
                obj = pickle.loads(f.read())
        except:
            raise KeyError(key)

        self.cache[fil] = (obj,mtime)
        return obj

    def __setitem__(self,key,value):
        """ db['key'] = 5 """
        fil = self.root / key
        parent = fil.parent
        if parent and not parent.isdir():
            parent.makedirs()
        # We specify protocol 2, so that we can mostly go between Python 2
        # and Python 3. We can upgrade to protocol 3 when Python 2 is obsolete.
        with fil.open('wb') as f:
            pickled = pickle.dump(value, f, protocol=2)
        try:
            self.cache[fil] = (value,fil.mtime)
        except OSError as e:
            if e.errno != 2:
                raise

    def hset(self, hashroot, key, value):
        """ hashed set """
        hroot = self.root / hashroot
        if not hroot.isdir():
            hroot.makedirs()
        hfile = hroot / gethashfile(key)
        d = self.get(hfile, {})
        d.update( {key : value})
        self[hfile] = d



    def hget(self, hashroot, key, default = _sentinel, fast_only = True):
        """ hashed get """
        hroot = self.root / hashroot
        hfile = hroot / gethashfile(key)

        d = self.get(hfile, _sentinel )
        #print "got dict",d,"from",hfile
        if d is _sentinel:
            if fast_only:
                if default is _sentinel:
                    raise KeyError(key)

                return default

            # slow mode ok, works even after hcompress()
            d = self.hdict(hashroot)

        return d.get(key, default)

    def hdict(self, hashroot):
        """ Get all data contained in hashed category 'hashroot' as dict """
        hfiles = self.keys(hashroot + "/*")
        hfiles.sort()
        last = len(hfiles) and hfiles[-1] or ''
        if last.endswith('xx'):
            # print "using xx"
            hfiles = [last] + hfiles[:-1]

        all = {}

        for f in hfiles:
            # print "using",f
            try:
                all.update(self[f])
            except KeyError:
                print("Corrupt",f,"deleted - hset is not threadsafe!")
                del self[f]

            self.uncache(f)

        return all

    def hcompress(self, hashroot):
        """ Compress category 'hashroot', so hset is fast again

        hget will fail if fast_only is True for compressed items (that were
        hset before hcompress).

        """
        hfiles = self.keys(hashroot + "/*")
        all = {}
        for f in hfiles:
            # print "using",f
            all.update(self[f])
            self.uncache(f)

        self[hashroot + '/xx'] = all
        for f in hfiles:
            p = self.root / f
            if p.basename() == 'xx':
                continue
            p.remove()



    def __delitem__(self,key):
        """ del db["key"] """
        fil = self.root / key
        self.cache.pop(fil,None)
        try:
            fil.remove()
        except OSError:
            # notfound and permission denied are ok - we
            # lost, the other process wins the conflict
            pass

    def _normalized(self, p):
        """ Make a key suitable for user's eyes """
        return str(self.root.relpathto(p)).replace('\\','/')

    def keys(self, globpat = None):
        """ All keys in DB, or all keys matching a glob"""

        if globpat is None:
            files = self.root.walkfiles()
        else:
            files = [Path(p) for p in glob.glob(self.root/globpat)]
        return [self._normalized(p) for p in files if p.isfile()]

    def __iter__(self):
        return iter(list(self.keys()))

    def __len__(self):
        return len(list(self.keys()))

    def uncache(self,*items):
        """ Removes all, or specified items from cache

        Use this after reading a large amount of large objects
        to free up memory, when you won't be needing the objects
        for a while.

        """
        if not items:
            self.cache = {}
        for it in items:
            self.cache.pop(it,None)

    def waitget(self,key, maxwaittime = 60 ):
        """ Wait (poll) for a key to get a value

        Will wait for `maxwaittime` seconds before raising a KeyError.
        The call exits normally if the `key` field in db gets a value
        within the timeout period.

        Use this for synchronizing different processes or for ensuring
        that an unfortunately timed "db['key'] = newvalue" operation
        in another process (which causes all 'get' operation to cause a
        KeyError for the duration of pickling) won't screw up your program
        logic.
        """

        wtimes = [0.2] * 3 + [0.5] * 2 + [1]
        tries = 0
        waited = 0
        while 1:
            try:
                val = self[key]
                return val
            except KeyError:
                pass

            if waited > maxwaittime:
                raise KeyError(key)

            time.sleep(wtimes[tries])
            waited+=wtimes[tries]
            if tries < len(wtimes) -1:
                tries+=1

    def getlink(self,folder):
        """ Get a convenient link for accessing items  """
        return PickleShareLink(self, folder)

    def __repr__(self):
        return "PickleShareDB('%s')" % self.root
Esempio n. 6
0
class PickleShareDB(collections.MutableMapping):
    """ The main 'connection' object for PickleShare database """
    def __init__(self, root):
        """ Return a db object that will manage the specied directory"""
        self.root = Path(root).expanduser().abspath()
        if not self.root.isdir():
            self.root.makedirs()
        # cache has { 'key' : (obj, orig_mod_time) }
        self.cache = {}

    def __getitem__(self, key):
        """ db['key'] reading """
        fil = self.root / key
        try:
            mtime = (fil.stat()[stat.ST_MTIME])
        except OSError:
            raise KeyError(key)

        if fil in self.cache and mtime == self.cache[fil][1]:
            return self.cache[fil][0]
        try:
            # The cached item has expired, need to read
            with fil.open("rb") as f:
                obj = pickle.loads(f.read())
        except:
            raise KeyError(key)

        self.cache[fil] = (obj, mtime)
        return obj

    def __setitem__(self, key, value):
        """ db['key'] = 5 """
        fil = self.root / key
        parent = fil.parent
        if parent and not parent.isdir():
            parent.makedirs()
        # We specify protocol 2, so that we can mostly go between Python 2
        # and Python 3. We can upgrade to protocol 3 when Python 2 is obsolete.
        with fil.open('wb') as f:
            pickled = pickle.dump(value, f, protocol=2)
        try:
            self.cache[fil] = (value, fil.mtime)
        except OSError as e:
            if e.errno != 2:
                raise

    def hset(self, hashroot, key, value):
        """ hashed set """
        hroot = self.root / hashroot
        if not hroot.isdir():
            hroot.makedirs()
        hfile = hroot / gethashfile(key)
        d = self.get(hfile, {})
        d.update({key: value})
        self[hfile] = d

    def hget(self, hashroot, key, default=_sentinel, fast_only=True):
        """ hashed get """
        hroot = self.root / hashroot
        hfile = hroot / gethashfile(key)

        d = self.get(hfile, _sentinel)
        #print "got dict",d,"from",hfile
        if d is _sentinel:
            if fast_only:
                if default is _sentinel:
                    raise KeyError(key)

                return default

            # slow mode ok, works even after hcompress()
            d = self.hdict(hashroot)

        return d.get(key, default)

    def hdict(self, hashroot):
        """ Get all data contained in hashed category 'hashroot' as dict """
        hfiles = self.keys(hashroot + "/*")
        hfiles.sort()
        last = len(hfiles) and hfiles[-1] or ''
        if last.endswith('xx'):
            # print "using xx"
            hfiles = [last] + hfiles[:-1]

        all = {}

        for f in hfiles:
            # print "using",f
            try:
                all.update(self[f])
            except KeyError:
                print("Corrupt", f, "deleted - hset is not threadsafe!")
                del self[f]

            self.uncache(f)

        return all

    def hcompress(self, hashroot):
        """ Compress category 'hashroot', so hset is fast again

        hget will fail if fast_only is True for compressed items (that were
        hset before hcompress).

        """
        hfiles = self.keys(hashroot + "/*")
        all = {}
        for f in hfiles:
            # print "using",f
            all.update(self[f])
            self.uncache(f)

        self[hashroot + '/xx'] = all
        for f in hfiles:
            p = self.root / f
            if p.basename() == 'xx':
                continue
            p.remove()

    def __delitem__(self, key):
        """ del db["key"] """
        fil = self.root / key
        self.cache.pop(fil, None)
        try:
            fil.remove()
        except OSError:
            # notfound and permission denied are ok - we
            # lost, the other process wins the conflict
            pass

    def _normalized(self, p):
        """ Make a key suitable for user's eyes """
        return str(self.root.relpathto(p)).replace('\\', '/')

    def keys(self, globpat=None):
        """ All keys in DB, or all keys matching a glob"""

        if globpat is None:
            files = self.root.walkfiles()
        else:
            files = [Path(p) for p in glob.glob(self.root / globpat)]
        return [self._normalized(p) for p in files if p.isfile()]

    def __iter__(self):
        return iter(list(self.keys()))

    def __len__(self):
        return len(list(self.keys()))

    def uncache(self, *items):
        """ Removes all, or specified items from cache

        Use this after reading a large amount of large objects
        to free up memory, when you won't be needing the objects
        for a while.

        """
        if not items:
            self.cache = {}
        for it in items:
            self.cache.pop(it, None)

    def waitget(self, key, maxwaittime=60):
        """ Wait (poll) for a key to get a value

        Will wait for `maxwaittime` seconds before raising a KeyError.
        The call exits normally if the `key` field in db gets a value
        within the timeout period.

        Use this for synchronizing different processes or for ensuring
        that an unfortunately timed "db['key'] = newvalue" operation
        in another process (which causes all 'get' operation to cause a
        KeyError for the duration of pickling) won't screw up your program
        logic.
        """

        wtimes = [0.2] * 3 + [0.5] * 2 + [1]
        tries = 0
        waited = 0
        while 1:
            try:
                val = self[key]
                return val
            except KeyError:
                pass

            if waited > maxwaittime:
                raise KeyError(key)

            time.sleep(wtimes[tries])
            waited += wtimes[tries]
            if tries < len(wtimes) - 1:
                tries += 1

    def getlink(self, folder):
        """ Get a convenient link for accessing items  """
        return PickleShareLink(self, folder)

    def __repr__(self):
        return "PickleShareDB('%s')" % self.root