Automatically Find PGP Keys in Mu4e

I have found a peculiar delight in encryption, and particularly in using pgp-based asymmetric cryptography. This is especially useful for securing email communications, but doing so requires remembering to run M-x mml-secure-sign or mml-secure-encrypt in Mail Utilities For Emacs (Mu4e) before sending the message. For this reason I have been wanting to write a quick method that automatically adds signing capabilities and encryption only the recipient has a public key. Thankfully, I did not have to do so because of Nicolas Cavigneaux’s recent post Sign Always, Encrypt When Possible where he showcases his functins for doing exactly that. It prompted me to tweak it slightly, and to add the functionality to automatically discover public keys that I have yet to import. Cavigneaux’s post sets up an elegant arrangement: email should always be signed with your pgp key, and you should “upgrade” from there to encryption only if your correspondent can handle encrypted mail and has shared their…