Fix DNF idempotency. (#66209)

changelogs/fragments/64963-dnf_idempotence.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - "dnf - Fix idempotence of `state: installed` (https://github.com/ansible/ansible/issues/64963)"

lib/ansible/modules/packaging/os/dnf.py

@@ -724,38 +724,30 @@ class DnfModule(YumDnf):
         is_newer_version_installed = self._is_newer_version_installed(pkg_spec)
         is_installed = self._is_installed(pkg_spec)
         try:
-            if self.allow_downgrade:
-                # dnf only does allow_downgrade, we have to handle this ourselves
-                # because it allows a possibility for non-idempotent transactions
-                # on a system's package set (pending the yum repo has many old
-                # NVRs indexed)
-                if upgrade:
-                    if is_installed:
-                        self.base.upgrade(pkg_spec)
+            if is_newer_version_installed:
+                if self.allow_downgrade:
+                    # dnf only does allow_downgrade, we have to handle this ourselves
+                    # because it allows a possibility for non-idempotent transactions
+                    # on a system's package set (pending the yum repo has many old
+                    # NVRs indexed)
+                    if upgrade:
+                        if is_installed:
+                            self.base.upgrade(pkg_spec)
+                        else:
+                            self.base.install(pkg_spec)
                     else:
                         self.base.install(pkg_spec)
-                else:
-                    self.base.install(pkg_spec)
-            elif not self.allow_downgrade and is_newer_version_installed:
-                return {'failed': False, 'msg': '', 'failure': '', 'rc': 0}
-            elif not is_newer_version_installed:
+                else:  # Nothing to do, report back
+                    pass
+            elif is_installed:  # An potentially older (or same) version is installed
                 if upgrade:
-                    if is_installed:
-                        self.base.upgrade(pkg_spec)
-                    else:
-                        self.base.install(pkg_spec)
-                else:
-                    self.base.install(pkg_spec)
-            else:
-                if upgrade:
-                    if is_installed:
-                        self.base.upgrade(pkg_spec)
-                    else:
-                        self.base.install(pkg_spec)
-                else:
-                    self.base.install(pkg_spec)
+                    self.base.upgrade(pkg_spec)
+                else:  # Nothing to do, report back
+                    pass
+            else:  # The package is not installed, simply install it
+                self.base.install(pkg_spec)
 
-            return {'failed': False, 'msg': 'Installed: {0}'.format(pkg_spec), 'failure': '', 'rc': 0}
+            return {'failed': False, 'msg': '', 'failure': '', 'rc': 0}
 
         except dnf.exceptions.MarkingError as e:
             return {
@@ -1010,10 +1002,12 @@ class DnfModule(YumDnf):
                     for pkg_spec in pkg_specs:
                         install_result = self._mark_package_install(pkg_spec)
                         if install_result['failed']:
-                            failure_response['msg'] += install_result['msg']
+                            if install_result['msg']:
+                                failure_response['msg'] += install_result['msg']
                             failure_response['failures'].append(self._sanitize_dnf_error_msg_install(pkg_spec, install_result['failure']))
                         else:
-                            response['results'].append(install_result['msg'])
+                            if install_result['msg']:
+                                response['results'].append(install_result['msg'])
 
             elif self.state == 'latest':
                 # "latest" is same as "installed" for filenames.
@@ -1070,10 +1064,12 @@ class DnfModule(YumDnf):
                         self.base.conf.best = True
                         install_result = self._mark_package_install(pkg_spec, upgrade=True)
                         if install_result['failed']:
-                            failure_response['msg'] += install_result['msg']
+                            if install_result['msg']:
+                                failure_response['msg'] += install_result['msg']
                             failure_response['failures'].append(self._sanitize_dnf_error_msg_install(pkg_spec, install_result['failure']))
                         else:
-                            response['results'].append(install_result['msg'])
+                            if install_result['msg']:
+                                response['results'].append(install_result['msg'])
 
             else:
                 # state == absent

test/integration/targets/dnf/tasks/repo.yml

@@ -41,6 +41,24 @@
         that:
             - "'msg' in dnf_result"
     # ============================================================================
+    - name: Install dinginessentail again (noop, module is idempotent)
+      dnf:
+        name: dinginessentail
+        state: present
+      register: dnf_result
+
+    - name: Check dinginessentail with rpm
+      shell: rpm -q dinginessentail
+      register: rpm_result
+
+    - name: Verify installation
+      assert:
+        that:
+            # No upgrade happened to 1.1.1
+            - "not dnf_result.changed"
+            # Old version still installed
+            - "rpm_result.stdout.startswith('dinginessentail-1.0-1')"
+    # ============================================================================
     - name: Install dinginessentail-1:1.0-2
       dnf:
         name: "dinginessentail-1:1.0-2.{{ ansible_architecture }}"