pythonencryptiongnupgkeyserverpython-gnupgp

How to Python gnupg (GPG) encrypt with recipient's email address rather than their fingerprint?


How to Python-gnupg (GnuPG / GPG / OpenPGP) encrypt with recipient's email address rather than their fingerprint?

This example shows (which failes on my Ubuntu 20.04 / such a thing, but it's an old example; excerpt:

encrypted_data = gpg.encrypt(unencrypted_string, 'testgpguser@mydomain.com')

More-current (maybe?) references (like this and this) do not mention recipient email addresses, seemingly requiring numeric-only fingerprints for (presumably) public-key identication. Is it possible in today's environment (to identify a key solely by it's associated email_address/identity)? Possibly requiring a keyserver?

My tested python-gnupg system versions.


Solution

  • Looking at the version number in your question, you appear to be using the pretty-bad-protocol rewrite, which hasn't been updated since 2018.

    If you simply install python-gnupg:

    $ pip install python-gnupg
    

    You get version 0.4.9, which was released just a few days ago:

    Collecting python-gnupg
      Downloading http://.../python_gnupg-0.4.9-py2.py3-none-any.whl (18 kB)
    Installing collected packages: python-gnupg
    Successfully installed python-gnupg-0.4.9
    

    Using this version of the gnupg module, your code works without a problem:

    >>> import gnupg
    >>> gpg = gnupg.G
    gnupg.GPG(     gnupg.GenKey(
    >>> gpg = gnupg.GPG()
    >>> res = gpg.encrypt("this is a test", "bob@example.com")
    >>> res.data
    b'-----BEGIN PGP MESSAGE-----\n...\n-----END PGP MESSAGE-----\n'
    >>>
    

    It is of course better to use a fingerprint, because you may have multiple keys in your keychain with the same email address, and you can't be certain which one you'll get. Using a fingerprint ensures that you get that specific key.