Enable testing Ceph master

This changeset adds a config option (TEST_MASTER)
to toggle testing with the current Ceph master.
The builds are retrieved from Shaman, which is the
platform used by the Ceph community to submit their
latest builds.

The main goal of this change is to use this on our CI
and be able to catch bugs in OpenStack services that use
Ceph as a backend more quickly. Because of this, the
required non-voting job is also added.

Change-Id: Ibe26f89e7be3061cdb7acb441727efb2c396e29e

.zuul.yaml

@@ -196,6 +196,17 @@
           REMOTE_CEPH: true
           CINDER_CEPH_UUID: d531d2d4-3937-429c-b0c2-658fe41e82aa
 
+- job:
+    name: devstack-plugin-ceph-master-tempest
+    parent: devstack-plugin-ceph-tempest-py3-base
+    description: |
+      Integration tests that runs with the ceph devstack plugin
+      using Ceph master as the backend.
+    branches: master
+    vars:
+      devstack_localrc:
+        TEST_MASTER: true
+
 - project-template:
     name: devstack-plugin-ceph-tempest-jobs
     description: |
@@ -211,6 +222,8 @@
             voting: false
         - devstack-plugin-ceph-tempest-fedora-latest
         - devstack-plugin-ceph-multinode-tempest-py3
+        - devstack-plugin-ceph-master-tempest:
+            voting: false
     gate:
       jobs:
         - devstack-plugin-ceph-tempest-py3

devstack/lib/ceph

@@ -26,6 +26,8 @@ set +o xtrace
 # Defaults
 # --------
 
+TEST_MASTER=$(trueorfalse False TEST_MASTER)
+
 CEPH_RELEASE=${CEPH_RELEASE:-octopus}
 
 GANESHA_RELEASE=${GANESHA_RELEASE:-V3.3-stable}
@@ -969,12 +971,23 @@ function configure_repo_ceph {
     local distro_release="$3"
 
     if  is_ubuntu; then
+        if [[ "${TEST_MASTER}" == "True" ]]; then
+            repo_file_name="/etc/apt/sources.list.d/ceph-master.list"
+            sudo wget -c "https://shaman.ceph.com/api/repos/ceph/master/latest/ubuntu/${distro_release}/flavors/default/repo" -O ${repo_file_name}
+        else
             wget -q -O- 'https://download.ceph.com/keys/release.asc' | sudo apt-key add -
             sudo apt-add-repository -y "deb https://download.ceph.com/debian-${ceph_release}/ ${distro_release} main"
+        fi
         sudo ${package_manager} -y update
     elif is_fedora; then
+        if [[ "${TEST_MASTER}" == "True" ]]; then
+            repo_file_name="/etc/yum.repos.d/ceph-master.repo"
+            sudo wget -c "https://shaman.ceph.com/api/repos/ceph/master/latest/centos/${distro_release}/flavors/default/repo" -O ${repo_file_name}
+            sudo dnf config-manager --add-repo ${repo_file_name}
+        else
             dnf_add_repository_ceph ${ceph_release} ${distro_release}
         fi
+    fi
 }
 
 # cleanup_repo_ceph() - Remove Ceph repositories