Ensure put returns key

[mlondschien]

First step towards #28.

[xhochy]

I think I have seen some cases (in the redis store?) where you can have new_key != key is key is None. Should we handle that here, too?

[mlondschien]

Here we return the key:

minimalkv/minimalkv/memory/redisstore.py

Lines 75 to 97 in 54cc308

	def _put(
	self, key: str, value: bytes, ttl_secs: Optional[Union[str, int, float]] = None
	) -> str:
	assert ttl_secs is not None
	if ttl_secs in (NOT_SET, FOREVER):
	# if we do not care about ttl, just use set
	# in redis, using SET will also clear the timeout
	# note that this assumes that there is no way in redis
	# to set a default timeout on keys
	self.redis.set(key, value)
	else:
	ittl = None
	try:
	ittl = int(ttl_secs)
	except ValueError:
	pass # let it blow up further down
	if ittl == ttl_secs:
	self.redis.setex(key, ittl, value)
	else:
	self.redis.psetex(key, int(ttl_secs * 1000), value)
	return key

I guess there it the KeyTransformingDecorator (undocumented):

minimalkv/minimalkv/decorator.py

Lines 101 to 102 in 54cc308

	def put(self, key: str, *args, **kwargs): # noqa D
	return self._unmap_key(self._dstore.put(self._map_key(key), *args, **kwargs))

and the HashDecorator:

minimalkv/minimalkv/idgen.py

Lines 49 to 75 in 54cc308

	def put(self, key: Optional[str], data: bytes, *args, **kwargs):
	"""Store bytestring data at key.
	Parameters
	----------
	key : str or None
	The key under which the data is to be stored. If None, the hash of data is
	used.
	data : bytes
	Data to be stored at key, must be of type ``bytes``.
	Returns
	-------
	str
	The key under which data was stored.
	Raises
	------
	ValueError
	If the key is not valid.
	IOError
	If storing failed or the file could not be read.
	"""
	if key is None:
	key = self._template.format(self.hashfunc(data).hexdigest())
	return self._dstore.put(key, data, *args, **kwargs) # type: ignore

The former is surely untested (else tests would be failing).

[mlondschien]

Let's merge this and then worry about other methods later.