Example for generating keys

[mm28ajos]

Hey there,
greate work, thanks a lot! I was just wondering how to operational generate a key pair, store/export it and then use it to fetch reports. Could you give an example / add one to the example folder? Thanks!

[malmeloo]

Hey! I'll add a proper example soon, but for now, this should give you an idea:

>>> import findmy
>>> 
>>> key = findmy.KeyPair.new()
>>> print(key)
KeyPair(name="None", public_key="VLAlUkbtl5UW0nKFt2gJaifiNMHoVkNvVnaBmA==", type=KeyType.UNKNOWN)
>>> 
>>> print(key.private_key_b64)  # this is a string!
CDGVABJiyAgFgDO0/ySK8od3k+me5JJPfOA9nQ==
>>>
>>> key_str = key.private_key_b64 
>>> new_key = findmy.KeyPair.from_b64(key_str)  # import the key
>>>
>>> key == new_key
True

You can then use the KeyPair object to fetch reports, see the existing examples for details.

[mm28ajos]

Thanks!

[mm28ajos]

Could you extend the example on how to handle key generation for devices which could roll over keys i.e. change advertisement keys regularly from a fixed pool of keys? How would I fetch reports for a devices with multiple keys?

[malmeloo]

For a set of keys that's fixed in advance? There are multiple ways to do that, but the most elegant way would be to extend RollingKeyPairSource and implement its methods to always return the same set of keys. An instance of this class can then be passed to the regular fetch_reports method, just like a regular KeyPair.

I will add it to the list of feature requests, it's not very difficult to implement so it can probably make it into the next release.

[mm28ajos]

Yes, I guess that is what I want to achieve, not 100% sure I expressed it correctly, so here same more details: I found this alternative OpenHaystack firmware which allows to flash multiple advertising keys on the chip and then uses one of those keys in a rotating manner to make tracking by third parties more difficult. So I need to fetch reports for all those flashed keys in one query.

There is another repo I found which does this already but uses the biemster code. See request_reports function there.