tests: fix package and ca_cert cloud_tests on bionic

package_update_upgrade_install was failing as htop is now included in
Bionic images.  Switch this test to install 'sl' instead.

ca_certs integration test fails on cert_count test because bionic
update-ca-certificates on bionic generates less symlinks for a given cert.

Integration tests now collect dpkg-query --show output on every instance.
Add a new assertPackageInstalled helper method which finds the package or
package version installed on the instance.

Adapt existing byobu, package_update_upgrade_install, ntp and salt_minion
tests to use assertPackageInstalled method.

LP: #1769985

1 files changed, 21 insertions, 0 deletions

diff --git a/tests/cloud_tests/testcases/base.py b/tests/cloud_tests/testcases/base.py
index 0d1916b4..696db8dd 100644
--- a/tests/cloud_tests/testcases/base.py
+++ b/tests/cloud_tests/testcases/base.py
@@ -31,6 +31,27 @@ class CloudTestCase(unittest.TestCase):
     def is_distro(self, distro_name):
         return self.os_cfg['os'] == distro_name
 
+    def assertPackageInstalled(self, name, version=None):
+        """Check dpkg-query --show output for matching package name.
+
+        @param name: package base name
+        @param version: string representing a package version or part of a
+            version.
+        """
+        pkg_out = self.get_data_file('package-versions')
+        pkg_match = re.search(
+            '^%s\t(?P<version>.*)$' % name, pkg_out, re.MULTILINE)
+        if pkg_match:
+            installed_version = pkg_match.group('version')
+            if not version:
+                return  # Success
+            if installed_version.startswith(version):
+                return  # Success
+            raise AssertionError(
+                'Expected package version %s-%s not found. Found %s' %
+                name, version, installed_version)
+        raise AssertionError('Package not installed: %s' % name)
+
     def os_version_cmp(self, cmp_version):
         """Compare the version of the test to comparison_version.