pycassa.util
– Utilities¶
A combination of utilities used internally by pycassa and utilities available for use by others working with pycassa.
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pycassa.util.
convert_time_to_uuid
(time_arg, lowest_val=True, randomize=False)¶ Converts a datetime or timestamp to a type 1
uuid.UUID
.This is to assist with getting a time slice of columns or creating columns when column names are
TimeUUIDType
. Note that this is done automatically in most cases if name packing and value packing are enabled.Also, be careful not to rely on this when specifying a discrete set of columns to fetch, as the non-timestamp portions of the UUID will be generated randomly. This problem does not matter with slice arguments, however, as the non-timestamp portions can be set to their lowest or highest possible values.
Parameters: - datetime (
datetime
or timestamp) – The time to use for the timestamp portion of the UUID. Expected inputs to this would either be adatetime
object or a timestamp with the same precision produced bytime.time()
. That is, sub-second precision should be below the decimal place. - lowest_val (bool) – Whether the UUID produced should be the lowest possible value UUID with the same timestamp as datetime or the highest possible value.
- randomize (bool) – Whether the clock and node bits of the UUID should be randomly generated. The lowest_val argument will be ignored if this is true.
Return type: uuid.UUID
Changed in version 1.7.0: Prior to 1.7.0, datetime objects were expected to be in local time. In 1.7.0 and beyond, naive datetimes are assumed to be in UTC and tz-aware objects will be automatically converted to UTC.
- datetime (
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pycassa.util.
convert_uuid_to_time
(uuid_arg)¶ Converts a version 1
uuid.UUID
to a timestamp with the same precision astime.time()
returns. This is useful for examining the results of queries returning a v1UUID
.Parameters: uuid_arg – a version 1 UUID
Return type: timestamp
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class
pycassa.util.
OrderedDict
(*args, **kwds)¶ A dictionary which maintains the insertion order of keys.
A dictionary which maintains the insertion order of keys.