Module utils default path (#20913)

* Make the module_utils path configurable
* Add a config value to define the path site module_utils files
* Handle module_utils that do not have source as an error
* Make an integration test for module_utils envvar working
* Add documentation for the ANSIBLE_MODULE_UTILS config option/envvar
* Add it to the sample ansible.cfg
* Add it to intro_configuration.
* Also modify intro_configuration to place envvars on equal footing with
  the config options (will need to document the envvar names in the
  future)
* Also add the ANSIBLE_LIBRARY use case from
  https://github.com/ansible/ansible/issues/15432 so we can close out
  that bug.

test/integration/targets/module_utils/library/test_env_override.py

@@ -0,0 +1,8 @@
+#!/usr/bin/python
+from ansible.module_utils.basic import AnsibleModule
+from ansible.module_utils.json_utils import data
+from ansible.module_utils.mork import data as mork_data
+
+results = {"json_utils": data, "mork": mork_data}
+
+AnsibleModule(argument_spec=dict()).exit_json(**results)

test/integration/targets/module_utils/module_utils/service.py

@@ -0,0 +1 @@
+sysv_is_enabled = 'sysv_is_enabled'

test/integration/targets/module_utils/module_utils_envvar.yml

@@ -0,0 +1,51 @@
+- hosts: localhost
+  gather_facts: no
+  tasks:
+  - name: Use a specially crafted module to see if things were imported correctly
+    test:
+    register: result
+
+  - name: Check that these are all loaded from playbook dir's module_utils
+    assert:
+      that:
+        - 'result["abcdefgh"] == "abcdefgh"'
+        - 'result["bar0"] == "bar0"'
+        - 'result["bar1"] == "bar1"'
+        - 'result["bar2"] == "bar2"'
+        - 'result["baz1"] == "baz1"'
+        - 'result["baz2"] == "baz2"'
+        - 'result["foo0"] == "foo0"'
+        - 'result["foo1"] == "foo1"'
+        - 'result["foo2"] == "foo2"'
+        - 'result["qux1"] == "qux1"'
+        - 'result["qux2"] == ["qux2:quux", "qux2:quuz"]'
+        - 'result["spam1"] == "spam1"'
+        - 'result["spam2"] == "spam2"'
+        - 'result["spam3"] == "spam3"'
+        - 'result["spam4"] == "spam4"'
+        - 'result["spam5"] == ["spam5:bacon", "spam5:eggs"]'
+        - 'result["spam6"] == ["spam6:bacon", "spam6:eggs"]'
+        - 'result["spam7"] == ["spam7:bacon", "spam7:eggs"]'
+        - 'result["spam8"] == ["spam8:bacon", "spam8:eggs"]'
+
+  # Test that overriding something in module_utils with something in the local library works
+  - name: Test that playbook dir's module_utils overrides facts.py
+    test_override:
+    register: result
+
+  - name: Make sure the we used the local facts.py, not the one shipped with ansible
+    assert:
+      that:
+        - 'result["data"] == "overridden facts.py"'
+
+  - name: Test that importing something from the module_utils in the env_vars works
+    test_env_override:
+    register: result
+
+  - name: Make sure we used the module_utils from the env_var for these
+    assert:
+      that:
+        # Override of shipped module_utils
+        - 'result["json_utils"] == "overridden json_utils"'
+        # Only i nthe env vars directory
+        - 'result["mork"] == "mork"'

test/integration/targets/module_utils/module_utils_test.yml

@@ -43,8 +43,9 @@
     ignore_errors: True
     register: result
 
+  - debug: var=result
   - name: Make sure we failed in AnsiBallZ
     assert:
       that:
         - 'result["failed"] == True'
-        - '"Could not find imported module support code for test_failure.  Looked for either foo or zebra" == result["msg"]'
+        - '"Could not find imported module support code for test_failure.  Looked for either foo.py or zebra.py" == result["msg"]'

test/integration/targets/module_utils/other_mu_dir/a/b/c/d/e/f/g/h/__init__.py

@@ -0,0 +1 @@
+data = 'should not be visible abcdefgh'

test/integration/targets/module_utils/other_mu_dir/facts.py

@@ -0,0 +1 @@
+data = 'should not be visible facts.py'

test/integration/targets/module_utils/other_mu_dir/json_utils.py

@@ -0,0 +1 @@
+data = 'overridden json_utils'

test/integration/targets/module_utils/other_mu_dir/mork.py

@@ -0,0 +1 @@
+data = 'mork'

test/integration/targets/module_utils/runme.sh

@@ -3,3 +3,4 @@
 set -eux
 
 ansible-playbook module_utils_test.yml -i ../../inventory -v "$@"
+ANSIBLE_MODULE_UTILS=$(pwd)/other_mu_dir ansible-playbook module_utils_envvar.yml -i ../../inventory -v "$@"