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Diffstat (limited to 'src/olpc/datastore/utils.py')
| -rw-r--r-- | src/olpc/datastore/utils.py | 162 |
1 files changed, 0 insertions, 162 deletions
diff --git a/src/olpc/datastore/utils.py b/src/olpc/datastore/utils.py deleted file mode 100644 index 0505463..0000000 --- a/src/olpc/datastore/utils.py +++ /dev/null @@ -1,162 +0,0 @@ -import datetime -import dbus -import re -import time - - -class Singleton(type): - """A singleton metaclass - - >>> class MyManager(object): - ... __metaclass__ = Singleton - >>> a = MyManager() - >>> b = MyManager() - >>> assert a is b - - """ - def __init__(cls,name,bases,dic): - super(Singleton,cls).__init__(name,bases,dic) - cls._instance=None - def __call__(cls,*args,**kw): - if cls._instance is None: - cls._instance=super(Singleton,cls).__call__(*args,**kw) - return cls._instance - -class partial: - def __init__(self, fun, *args, **kwargs): - self.fun = fun - self.pending = args - self.kwargs = kwargs - - def __call__(self, *args, **kwargs): - if kwargs and self.kwargs: - kw = self.kwargs.copy() - kw.update(kwargs) - else: - kw = kwargs or self.kwargs - - return self.fun(*(self.pending + args), **kw) - -def once(method): - "A decorator that runs a method only once." - attrname = "_called" - def decorated(self, *args, **kwargs): - try: - return getattr(method, attrname) - except AttributeError: - r = method(self, *args, **kwargs) - setattr(method, attrname, r) - return r - return decorated - - - -def create_uid(): - # this is linux specific but easily changed - # Python 2.5 has universal support for this built in - return open('/proc/sys/kernel/random/uuid', 'r').read()[:-1] - - -def options_for(dict, prefix, invert=False): - """return a dict of the filtered properties for keys with prefix. - prefix will be removed - - If invert is True then only those keys not matching prefix are returned. - - >>> assert options_for({'app.a.option' : 1, 'app.b.option' : 2}, 'app.b.')['option'] == 2 - """ - d = {} - l = len(prefix) - for k, v in dict.iteritems(): - if k.startswith(prefix): - if invert is False:d[k[l:]] = v - elif invert is True: - d[k] = v - - return d - - - -def _convert(arg): - # this recursively processes arguments sent over dbus and yields - # normalized versions - if isinstance(arg, (dbus.String, dbus.UTF8String)): - try: return arg.encode('utf-8') - except: return str(arg) - - if isinstance(arg, (dbus.Dictionary, dict)): - d = {} - for k, v in arg.iteritems(): - # here we call str on the lhs making it suitable for - # passing as keywords args - d[str(_convert(k))] = _convert(v) - return d - - if isinstance(arg, dbus.Array): - a = [] - for item in arg: - a.append(_convert(item)) - return a - return arg - - -def sanitize_dbus(method): - # decorator to produce an alternative version of arguments based on pure Python - # types. - def decorator(self, *args, **kwargs): - n = [] - for arg in args: n.append(_convert(arg)) - kw = _convert(kwargs) - return method(self, *n, **kw) - return decorator - -DATEFORMAT = "%Y-%m-%dT%H:%M:%S" -def timeparse(t, format=DATEFORMAT): - """Parse a time string that might contain fractions of a second. - - Fractional seconds are supported using a fragile, miserable hack. - Given a time string like '02:03:04.234234' and a format string of - '%H:%M:%S', time.strptime() will raise a ValueError with this - message: 'unconverted data remains: .234234'. If %S is in the - format string and the ValueError matches as above, a datetime - object will be created from the part that matches and the - microseconds in the time string. - """ - try: - return datetime.datetime(*time.strptime(t, format)[0:6]) - except ValueError, msg: - if "%S" in format: - msg = str(msg) - mat = re.match(r"unconverted data remains:" - " \.([0-9]{1,6})$", msg) - if mat is not None: - # fractional seconds are present - this is the style - # used by datetime's isoformat() method - frac = "." + mat.group(1) - t = t[:-len(frac)] - t = datetime.datetime(*time.strptime(t, format)[0:6]) - microsecond = int(float(frac)*1e6) - return t.replace(microsecond=microsecond) - else: - mat = re.match(r"unconverted data remains:" - " \,([0-9]{3,3})$", msg) - if mat is not None: - # fractional seconds are present - this is the style - # used by the logging module - frac = "." + mat.group(1) - t = t[:-len(frac)] - t = datetime.datetime(*time.strptime(t, format)[0:6]) - microsecond = int(float(frac)*1e6) - return t.replace(microsecond=microsecond) - - raise - - -def parse_timestamp_or_float(value): - result = None - try: - result = timeparse(value) - result = str(time.mktime(result.timetuple())) - except: - result = str(float(value)) - return result |