Add jenkins-slave element for nodepool

This should be the final step needed to stop puppet from running on
our images. This also will be the entry point for 3rd party CI users
still depending on jenkins.

Change-Id: I33a67f980289002618a55f4221dcf195dc4a787f
Signed-off-by: Paul Belanger <pabelanger@redhat.com>

nodepool/elements/jenkins-slave/extra-data.d/20-jenkins-user

@@ -0,0 +1,20 @@
+#!/bin/bash
+
+if [ ${DIB_DEBUG_TRACE:-0} -gt 0 ]; then
+    set -x
+fi
+set -eu
+set -o pipefail
+
+# TODO(pabelanger): Once we complete remove puppet from our diskimages, we
+# should also remove our default SSH key. Since only 3rdparty CI system would be
+# using this element moving forward, it doesn't make sense to bake in our
+# default key.
+NODEPOOL_SSH_KEY=${NODEPOOL_SSH_KEY:-AAAAB3NzaC1yc2EAAAADAQABAAABAQC6WutNHfM+YdnjeNFeaIpvxqt+9aDn95Ykpmc+fASSjlDZJtOrueH3ch/v08wkE4WQKg03i+t8VonqEwMGmApYA3VzFsURUQbxzlSz5kHlBQSqgz5JTwUmnt1RH5sePL5pkuJ6JgqJ8PxJod6fiD7YDjaKJW/wBzXGnGg2EkgqrkBQXYL4hyaPuSwsQF0Gdwg3QFqXl+R/GrM6FscUkkJzbjqGKI2GhLT8mf2BIMEAiMFhF5Wl4FFrbvhTfPfW+9VdcsiMxCXaxp00n1x1+Y7OqR5AZ/id0Lkz9ZoFVGS901OB/L4xXrvUtI2y+kIYeF6hxfmAl/zhY0eWzwo9lDPz}
+
+if [ -z $NODEPOOL_SSH_KEY ]; then
+    die "Can not find public key for jenkins user!"
+fi
+
+# save the public key inside the chroot
+echo "ssh-rsa $NODEPOOL_SSH_KEY" > $TMP_HOOKS_PATH/jenkins-user-ssh-public-key

nodepool/elements/jenkins-slave/install.d/20-jenkins-slave

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+if [ ${DIB_DEBUG_TRACE:-0} -gt 0 ]; then
+    set -x
+fi
+set -eu
+set -o pipefail
+
+groupadd jenkins
+useradd -g jenkins -m jenkins
+
+# this was copied from outside the chroot by extras.d
+_pub_key=/tmp/in_target.d/jenkins-user-ssh-public-key
+if [ ! -f $_pub_key ]; then
+    die "Can not find Jenkins public key!"
+fi
+
+mkdir /home/jenkins/.ssh
+chmod 700 /home/jenkins/.ssh
+
+cp $_pub_key /home/jenkins/.ssh/authorized_keys
+chmod 644 /home/jenkins/.ssh/authorized_keys
+
+cat > /home/jenkins/.gitconfig <<EOF
+[user]
+    name = OpenStack Jenkins
+    email = jenkins@openstack.org
+    signingkey = jenkins@openstack.org
+[gitreview]
+    rebase = false
+    username = jenkins
+EOF
+
+# cleanup everything to the right owner
+chown -R jenkins:jenkins /home/jenkins

nodepool/elements/nodepool-base/element-deps

@@ -1,3 +1,4 @@
+jenkins-slave
 package-installs
 pip-and-virtualenv
 puppet