add-apt-repository exits with 0 even when adding key failed

This failure breaks automated installation and such, even when re-trying because the caller that might retry does not know that this failed.

Our curtin vmtest hit this at https://jenkins.ubuntu.com/server/view/Curtin/job/curtin-vmtest-devel-amd64/781/consoleFull .

Merge proposal at https://code.launchpad.net/~smoser/software-properties/trunk.lp1532855/+merge/318132

This bug was fixed in the package software-properties - 0.96.24.11

---------------
software-properties (0.96.24.11) zesty; urgency=medium

  [Scott Moser]
  * debian/tests/run-tests: use gpg rather than gpg1, and show errors
    (LP: #1670399)
  * debian/tests/control: add gnupg to list of dependencies.

  [Iain Lane]
  * softwareproperties/shortcuts.py: Make add_key() return True. Since r988,
    the return value of add_key() is now used to raise an exception.
    ShortcutHandler.add_key() always succeeds, so should return True. This
    (LP: #1670399)

 -- Scott Moser <email address hidden> Mon, 06 Mar 2017 12:22:03 -0500

Hello Michał, or anyone else affected,

Accepted software-properties into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/software-properties/0.96.20.6 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

Hello Michał, or anyone else affected,

Accepted software-properties into yakkety-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/software-properties/0.96.24.7.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

## set up a container with software-properties installed from -proposed
$ rel=xenial
$ name=xenial-1
$ lxc launch ubuntu-daily:$rel $name
$ lxc exec $name -- sh -c 'while ! [ -e /run/cloud-init/result.json ]; do echo .; sleep 1; done' </dev/null
$ lxc exec $name -- sh -e <<"EOF"
rel=$(lsb_release -sc)
line=$(awk '$1 == "deb" && $2 ~ /ubuntu.com/ {
  printf("%s %s %s-proposed main universe\n", $1, $2, rel); exit(0) };
  ' "rel=$rel" /etc/apt/sources.list)
echo "$line" | sudo tee /etc/apt/sources.list.d/proposed.list
apt-get update -qq
apt-get install -qy software-properties-common </dev/null
EOF
...

$ lxc exec $name -- dpkg-query --show software-properties-common </dev/null
software-properties-common 0.96.20.6

$ lxc exec $name -- sh <<"EOF"
add-apt-repository ppa:launchpad/buildd-staging -k hkp://127.0.0.1/
echo exited with $?
EOF
 Buildd staging packages for Launchpad. New packages are staged here for testing on the staging PPA buildds.
 More info: https://launchpad.net/~launchpad/+archive/ubuntu/buildd-staging
gpg: keyring `/tmp/tmph5tjzyms/secring.gpg' created
gpg: keyring `/tmp/tmph5tjzyms/pubring.gpg' created
gpg: requesting key 0A5174AF from hkp server 127.0.0.1
gpg: no valid OpenPGP data found.
gpg: Total number processed: 0
gpg: keyserver communications error: keyserver unreachable
gpg: keyserver communications error: public key not found
gpg: keyserver receive failed: public key not found
?: 127.0.0.1: Connection refused
gpgkeys: HTTP fetch error 7: couldn't connect: Connection refused
Failed to add key.
exited with 1

## set up a container with software-properties installed from -proposed
$ rel=yakkety
$ name=yakkety-1
$ lxc launch ubuntu-daily:$rel $name
$ lxc exec $name -- sh -c 'while ! [ -e /run/cloud-init/result.json ]; do echo .; sleep 1; done' </dev/null
$ lxc exec $name -- sh -e <<"EOF"
rel=$(lsb_release -sc)
line=$(awk '$1 == "deb" && $2 ~ /ubuntu.com/ {
  printf("%s %s %s-proposed main universe\n", $1, $2, rel); exit(0) };
  ' "rel=$rel" /etc/apt/sources.list)
echo "$line" | sudo tee /etc/apt/sources.list.d/proposed.list
apt-get update -qq
apt-get install -qy software-properties-common </dev/null
EOF

$ lxc exec $name -- dpkg-query --show software-properties-common </dev/null
software-properties-common 0.96.24.7.1

$ lxc exec $name -- sh <<"EOF"
> add-apt-repository ppa:launchpad/buildd-staging -k hkp://bad-server
> echo exited with $?
> EOF
 Buildd staging packages for Launchpad. New packages are staged here for testing on the staging PPA buildds.
 More info: https://launchpad.net/~launchpad/+archive/ubuntu/buildd-staging
gpg: keybox '/tmp/tmpx3nk68ee/pubring.gpg' created
gpg: keyserver receive failed: No keyserver available
Failed to add key.
exited with 1

I opened bug 1671566 for a issue I found when testing this.
The fix is still valid, and we're in a strictly better scenario now than
we were before, but still a bug to fix.

This bug was fixed in the package software-properties - 0.96.24.7.1

---------------
software-properties (0.96.24.7.1) yakkety-proposed; urgency=medium

  * Add knowledge of OpenStack releases Ocata, Pike and Queens. (LP: #1670385)

  [ Scott Moser & Dimitri John Ledkov ]
  * When failing to retrieve a GPG key, raise an exception such that
    e.g. add-apt-repository can fail when it did not manage to retrieve a
    GPG key for the shortcut repository. LP: #1532855

 -- Scott Moser <email address hidden> Mon, 06 Mar 2017 17:15:20 -0500

The verification of the Stable Release Update for software-properties has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

I see dep8 failures in software-properties 0.96.20.6. But a recent test against 0.96.20.5 succeeded, which suggests to me that it is a regression caused by 0.96.20.6. I don't see anything obvious in the diff that could cause this, but I think it warrants further investigation. Please could you take a look?

See http://autopkgtest.ubuntu.com/packages/s/software-properties/xenial/i386 and http://autopkgtest.ubuntu.com/packages/s/software-properties/xenial/amd64

This bug was fixed in the package software-properties - 0.96.20.6

---------------
software-properties (0.96.20.6) xenial; urgency=medium

  * Add knowledge of OpenStack releases Pike and Queens. (LP: #1670385)

  [ Scott Moser & Dimitri John Ledkov ]
  * When failing to retrieve a GPG key, raise an exception such that
    e.g. add-apt-repository can fail when it did not manage to retrieve a
    GPG key for the shortcut repository. LP: #1532855

 -- Scott Moser <email address hidden> Mon, 06 Mar 2017 16:56:40 -0500