I've been hitting a problem when importing APT keys on a debian stretch VM. I'm using a property like

mybox :: Host
mybox = host "henry1.home" $ props
  & osDebian (Stable "stretch") X86_64
  & Apt.stdSourcesList
  & Apt.unattendedUpgrades
  & installKubernetes


installKubernetes :: Property DebianLike
installKubernetes = Apt.installed ["kubelet", "kubeadm", "kubectl"]
  `requires` Apt.setSourcesListD ["deb http://apt.kubernetes.io/ kubernetes-xenial main"] "google-cloud"
  `requires` Apt.trustsKey googleKey

googleKey :: Apt.AptKey
googleKey =
  Apt.AptKey "google-key" $ unlines
  [ "-----BEGIN PGP PUBLIC KEY BLOCK-----"
  , ""
  , "mQENBFUd6rIBCAD6mhKRHDn3UrCeLDp7U5IE7AhhrOCPpqGF7mfTemZYHf/5Jdjx"
  , "cOxoSFlK7zwmFr3lVqJ+tJ9L1wd1K6P7RrtaNwCiZyeNPf/Y86AJ5NJwBe0VD0xH"
  , "TXzPNTqRSByVYtdN94NoltXUYFAAPZYQls0x0nUD1hLMlOlC2HdTPrD1PMCnYq/N"
  , "uL/Vk8sWrcUt4DIS+0RDQ8tKKe5PSV0+PnmaJvdF5CKawhh0qGTklS2MXTyKFoqj"
  , "XgYDfY2EodI9ogT/LGr9Lm/+u4OFPvmN9VN6UG+s0DgJjWvpbmuHL/ZIRwMEn/tp"
  , "uneaLTO7h1dCrXC849PiJ8wSkGzBnuJQUbXnABEBAAG0QEdvb2dsZSBDbG91ZCBQ"
  , "YWNrYWdlcyBBdXRvbWF0aWMgU2lnbmluZyBLZXkgPGdjLXRlYW1AZ29vZ2xlLmNv"
  , "bT6JAT4EEwECACgFAlUd6rICGy8FCQWjmoAGCwkIBwMCBhUIAgkKCwQWAgMBAh4B"
  , "AheAAAoJEDdGwginMXsPcLcIAKi2yNhJMbu4zWQ2tM/rJFovazcY28MF2rDWGOnc"
  , "9giHXOH0/BoMBcd8rw0lgjmOosBdM2JT0HWZIxC/Gdt7NSRA0WOlJe04u82/o3OH"
  , "WDgTdm9MS42noSP0mvNzNALBbQnlZHU0kvt3sV1YsnrxljoIuvxKWLLwren/GVsh"
  , "FLPwONjw3f9Fan6GWxJyn/dkX3OSUGaduzcygw51vksBQiUZLCD2Tlxyr9NvkZYT"
  , "qiaWW78L6regvATsLc9L/dQUiSMQZIK6NglmHE+cuSaoK0H4ruNKeTiQUw/EGFaL"
  , "ecay6Qy/s3Hk7K0QLd+gl0hZ1w1VzIeXLo2BRlqnjOYFX4A="
  , "=HVTm"
  , "-----END PGP PUBLIC KEY BLOCK-----"
  ]

the import works fine, but the packages fail to install because the key isn't valid, i can list the key

root@henry1:~# apt-key list | grep -A 6 google-key
Warning: apt-key output should not be parsed (stdout is not a terminal)
/etc/apt/trusted.gpg.d/google-key.gpg
-------------------------------------
pub   rsa2048 2015-04-03 [SCEA] [expires: 2018-04-02]
      D0BC 747F D8CA F711 7500  D6FA 3746 C208 A731 7B0F
uid           [ unknown] Google Cloud Packages Automatic Signing Key <gc-team@google.com>

but i can't export it. I've tried the gpg command listed in the Apt.trustsKey function and running it locally (on the vm) with a local file doesn't work either.

root@henry1:~# apt-key export D6FA3746A7317B0F
gpg: [don't know]: invalid packet (ctb=00)
gpg: WARNING: nothing exported
gpg: key export failed: Invalid packet

Gpg version info

root@henry1:~# gpg --version
gpg (GnuPG) 2.1.18
libgcrypt 1.7.6-beta
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Home: /root/.gnupg
Supported algorithms:
Pubkey: RSA, ELG, DSA, ECDH, ECDSA, EDDSA
Cipher: IDEA, 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH,
        CAMELLIA128, CAMELLIA192, CAMELLIA256
Hash: SHA1, RIPEMD160, SHA256, SHA384, SHA512, SHA224
Compression: Uncompressed, ZIP, ZLIB, BZIP2

I ended up changing the Apt.trustsKey command to a version which uses apt-key and everything works now

trustsKey' :: AptKey -> Property DebianLike
trustsKey' k = check (not <$> doesFileExist f) $ property desc $ makeChange $ do
    withHandle StdinHandle createProcessSuccess
        (proc "apt-key" ["--keyring", f, "add", "-"]) $ \h -> do
            hPutStr h (pubkey k)
            hClose h
    nukeFile $ f ++ "~" -- gpg dropping
  where
    desc = "apt trusts key " ++ keyname k
    f = aptKeyFile k

Any thoughts as to why this wouldn't be working? Would it be reasonable to change this command upstream?