package_facts fix empty packages on foreign mgr (#83855)

* package_facts fix empty packages on foreign mgr

return the first package manager that provides output

add tests with fake rpm on apt machines

changelogs/fragments/package_facts_fix.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - package_facts module when using 'auto' will return the first package manager found that provides an output, instead of just the first one, as this can be foreign and not have any packages.

lib/ansible/modules/package_facts.py

@@ -460,7 +460,7 @@ def main():
 
     # get supported pkg managers
     PKG_MANAGERS = get_all_pkg_managers()
-    PKG_MANAGER_NAMES = [x.lower() for x in PKG_MANAGERS.keys()]
+    PKG_MANAGER_NAMES = sorted([x.lower() for x in PKG_MANAGERS.keys()])
     # add aliases
     PKG_MANAGER_NAMES.extend([alias for alist in ALIASES.values() for alias in alist])
 
@@ -510,12 +510,24 @@ def main():
 
         manager = PKG_MANAGERS[pkgmgr]()
         try:
+            packages_found = {}
             if manager.is_available(handle_exceptions=False):
-                found += 1
                 try:
-                    packages.update(manager.get_packages())
+                    packages_found = manager.get_packages()
                 except Exception as e:
                     module.warn('Failed to retrieve packages with %s: %s' % (pkgmgr, to_text(e)))
+
+            # only consider 'found' if it results in something
+            if packages_found:
+                found += 1
+                for k in packages_found.keys():
+                    if k in packages:
+                        packages[k].extend(packages_found[k])
+                    else:
+                        packages[k] = packages_found[k]
+            else:
+                module.warn('Found "%s" but no associated packages' % (pkgmgr))
+
         except Exception as e:
             if pkgmgr in module.params['manager']:
                 module.warn('Requested package manager %s was not usable by this module: %s' % (pkgmgr, to_text(e)))

test/integration/targets/package_facts/tasks/main.yml

@@ -18,6 +18,46 @@
     - name: check for ansible_facts.packages exists
       assert:
         that: ansible_facts.packages is defined
+
+    - name: Now try again but installing misleading rpm
+      block:
+        - name: install misleading rpm api
+          package: name="python3-rpm" state=present
+
+        - name: prep outputdir
+          tempfile: path=~ state=directory
+          register: tempdir
+
+        - name: install misleading rpm 'binary' file
+          file: dest="{{tempdir['path']}}/rpm" state=touch mode='0700'
+
+        - name: Gather package facts, finding 'rpm' on debian fam (needed for latest version)
+          package_facts:
+          environment:
+            PATH: "${PATH}:{{tempdir['path']}}"
+
+        - name: check we got packages
+          assert:
+            that:
+              - (ansible_facts.packages | length ) > 0
+
+        - name: Same again but this time forcing rpm first
+          package_facts:
+             manager: ['rpm', 'apt']
+          environment:
+            PATH: "${PATH}:{{tempdir['path']}}"
+
+        - name: check we got packages
+          assert:
+            that:
+              - (ansible_facts.packages | length ) > 0
+
+      always:
+        - package: name="python3-rpm" state=absent
+        - file: path="{{tempdir['path']}}/rpm" state=absent
+        - file: path="{{tempdir['path']}}" state=absent
+
+
   when: ansible_os_family == "Debian"
 
 - name: Run package_fact tests - Red Hat Family