Difference between revisions of "Python Problems"

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This patch simply replaces datetime.strptime with time.strptime. They are nearly identical in function. For more information, see: https://github.com/fbacher/script.module.kutils/blob/master/lib/kutils/strptime_patch.py. Essentially the patch is:
This patch simply replaces datetime.strptime with time.strptime. They are nearly identical in function. For more information, see: https://github.com/fbacher/script.module.kutils/blob/master/lib/kutils/strptime_patch.py. Essentially the patch is:


<nowiki> @staticmethod
  @staticmethod
     def monkey_patch_strptime():
     def monkey_patch_strptime():
         # Check if problem exists (don't want to stomp on patch applied earlier)
         # Check if problem exists (don't want to stomp on patch applied earlier)
Line 17: Line 17:
             # Globally replace Python's datetime.datetime.strptime with
             # Globally replace Python's datetime.datetime.strptime with
             # the version here.
             # the version here.
             datetime.datetime = StripTimePatch.strptime
             datetime.datetime = StripTimePatch.strptime
 
    @staticmethod
  @staticmethod
     def strptime(date_string: str, date_format: str) -> datetime.datetime:
     def strptime(date_string: str, date_format: str) -> datetime.datetime:
         result: datetime.datetime
         result: datetime.datetime
         result = datetime.datetime(*(time.strptime(date_string, date_format)[0:6]))
         result = datetime.datetime(*(time.strptime(date_string, date_format)[0:6]))
         return result
         return result
</nowiki>
 
[[Category:Development]]

Latest revision as of 21:05, 19 March 2022

This page is meant to document Python issues of general interest to Kodi addon developers.

datetime.strptime

There is an old Python bug (https://bugs.python.org/issue27400) which ONLY impacts embedded python applications, such as the Kodi Python environment. The issue is that datetime.strptime is only initialized once per process and not every time the embedded environment is reinitialized. This causes datetime.strptime to return None and perhaps other strange behavior.

One option is for you to replace every reference to datetime.strptime to use a strptime_patch attached to this page. This is less voodoo, but there is always the possibility that some library code uses strptime and there will still be potential for incorrect results or a Kodi crash (script.module.youtube.dl crashed Kodi for a while).

The other option is to monkey-patch datetime.strptime so that any user of the python runtime will use it. It is voodoo like, but that is why Python supports Monkey patching. See Python documentation on datetime.strptime (https://docs.python.org/3/library/datetime.html#strftime-strptime-behavior). It discusses some of the differences between datetime.strptime and time.strptime.

This patch simply replaces datetime.strptime with time.strptime. They are nearly identical in function. For more information, see: https://github.com/fbacher/script.module.kutils/blob/master/lib/kutils/strptime_patch.py. Essentially the patch is:

  @staticmethod
   def monkey_patch_strptime():
       # Check if problem exists (don't want to stomp on patch applied earlier)
       try:
           datetime.datetime.strptime('0', '%H')
       except TypeError:
           # Globally replace Python's datetime.datetime.strptime with
           # the version here.
           datetime.datetime = StripTimePatch.strptime
   @staticmethod
   def strptime(date_string: str, date_format: str) -> datetime.datetime:
       result: datetime.datetime
       result = datetime.datetime(*(time.strptime(date_string, date_format)[0:6]))
       return result