cachehitrate implies a rate but is used as a boolean flag

[HerrHorizontal]

The cachehitrate parameter in RequestedFiles_HitrateBased is currently used as a boolean despite being an integer.

lapis.caching/lapis/caching/files.py

Lines 86 to 98 in 8f4f614

	class RequestedFile_HitrateBased(RequestedFile):
	"""
	Represents a requested file in hitrate based caching.
	The cachehitrate flag is somewhat messed up currently.
	**Its use should be reworked when remodeling the connection module.**
	"""
	__slots__ = "cachehitrate"
	def __init__(self, filename: str, filesize: int, cachehitrate: int):
	super().__init__(filename, filesize)
	"""flag whether the file is cached, 1 if it is cached, 0 if it is not cached"""
	self.cachehitrate = cachehitrate

Since the meaning of a rate implies a percentage, this either needs a renaming or checking if the application of cachehitrate in terms of a rate does not change expectation, e.g. in the HitrateStorage and FileBasedHitrateStorage implementation.
Here the cachehitrate is used in two different ways,

• as a boolean in the transfer method for FileBasedHitrateStorage

lapis.caching/lapis/caching/storageelement.py

Lines 361 to 367 in 8f4f614

	if file.cachehitrate:
	await self.connection.transfer(total=file.filesize)
	await sampling_required.put(self.connection)
	else:
	print("wants to read from remote")
	print("file is not cached but cache is file source, this should not occur")
	raise ValueError

• as a multiplicative factor in the find method for FileBasedHitrateStorage

lapis.caching/lapis/caching/storageelement.py

Line 377 in 8f4f614

return LookUpInformation(file.filesize * file.cachehitrate, self)

• as a multiplicative factor in transfer for HitrateStorage (however, this class is out of date already)

lapis.caching/lapis/caching/storageelement.py

Line 285 in 8f4f614

hitrate_size = self._hitrate * file.filesize

As the current implementation already ensures correct functioning also with rates, I would propose to actually interpret it as it is named already. This means the following should be done:

• adaptation of docstrings to remove mentioning of interpretation as a flag
• adaptation of typehints
• unit tests to ensure that everything works as expected