npm: improve parameter validation (#10983)

* npm: improve parameter validation

* add changelog frag

* add required_if clause

* fix required_if, add required_one_of, add docs

* Update plugins/modules/npm.py

* Update plugins/modules/npm.py

* Update plugins/modules/npm.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/modules/npm.py

Co-authored-by: Felix Fontein <felix@fontein.de>

---------

Co-authored-by: Felix Fontein <felix@fontein.de>

changelogs/fragments/10983-npm-param-mutex.yml

@@ -0,0 +1,2 @@
+minor_changes:
+  - npm - improve parameter validation using Ansible construct (https://github.com/ansible-collections/community.general/pull/10983).

plugins/modules/npm.py

@@ -28,6 +28,7 @@ options:
   path:
     description:
       - The base path where to install the node.js libraries.
+      - When O(global=true), then O(path) is not used to install the packages.
     type: path
     required: false
   version:
@@ -38,6 +39,7 @@ options:
   global:
     description:
       - Install the node.js library globally.
+      - When O(global=true), then O(path) is not used to install the packages.
     required: false
     default: false
     type: bool
@@ -303,7 +305,10 @@ def main():
     arg_spec['global'] = dict(default=False, type='bool')
     module = AnsibleModule(
         argument_spec=arg_spec,
-        required_if=[('state', 'absent', ['name'])],
+        required_if=[
+            ('state', 'absent', ['name']),
+            ("global", False, ["path"]),
+        ],
         supports_check_mode=True,
     )
 
@@ -313,9 +318,6 @@ def main():
     glbl = module.params['global']
     state = module.params['state']
 
-    if not path and not glbl:
-        module.fail_json(msg='path must be specified when not using global')
-
     npm = Npm(module,
               name=name,
               path=path,