ipaserver: Allow execution of plugin in client host.

Update server README file and add tests for executing plugin with
`ipaapi_context` set to `client`.

A new test playbook can be found at:

    tests/server/test_server_client_context.yml

The new test file can be executed in a FreeIPA client host that is
not a server. In this case, it should be defined in the `ipaclients`
group, in the inventory file.

README-server.md

@@ -230,6 +230,7 @@ Variable | Description | Required
 -------- | ----------- | --------
 `ipaadmin_principal` | The admin principal is a string and defaults to `admin` | no
 `ipaadmin_password` | The admin password is a string and is required if there is no admin ticket available on the node | no
+`ipaapi_context` | The context in which the module will execute. Executing in a server context is preferred. If not provided context will be determined by the execution environment. Valid values are `server` and `client`. | no
 `name` \| `cn` | The list of server name strings. | yes
 `location` \| `ipalocation_location` | The server location string. Only in state: present. "" for location reset. | no
 `service_weight` \| `ipaserviceweight` | Weight for server services. Type Values 0 to 65535, -1 for weight reset. Only in state: present. (int) | no

tests/server/test_server.yml

 ---
 - name: Test server
-  hosts: ipaserver
+  hosts: "{{ ipa_test_host | default('ipaserver') }}"
   become: true
   gather_facts: yes
 
@@ -30,18 +30,21 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" without location
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       location: ""
 
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" without service weight
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       service_weight: -1
 
   - name: Ensure location "mylocation" is absent
     ipalocation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: mylocation
       state: absent
 
@@ -50,6 +53,7 @@
   - name: Ensure location "mylocation" is present
     ipalocation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: mylocation
     register: result
     failed_when: not result.changed or result.failed
@@ -59,6 +63,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" is present
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
     register: result
     failed_when: result.changed or result.failed
@@ -66,6 +71,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" with location "mylocation"
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       location: "mylocation"
     register: result
@@ -74,6 +80,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" with location "mylocation" again
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       location: "mylocation"
     register: result
@@ -82,6 +89,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" without location
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       location: ""
     register: result
@@ -90,6 +98,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" without location again
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       location: ""
     register: result
@@ -98,6 +107,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" with service weight 1
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       service_weight: 1
     register: result
@@ -106,6 +116,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" with service weight 1 again
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       service_weight: 1
     register: result
@@ -114,6 +125,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" without service weight
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       service_weight: -1
     register: result
@@ -122,6 +134,7 @@
   - name: Ensure server "{{ ipa_server_name + '.' + ipaserver_domain }}" without service weight again
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ ipa_server_name + '.' + ipaserver_domain }}"
       service_weight: -1
     register: result
@@ -134,6 +147,7 @@
   - name: Ensure server "{{ 'absent.' + ipaserver_domain }}" is absent
     ipaserver:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "{{ 'absent.' + ipaserver_domain }}"
       state: absent
     register: result
@@ -148,6 +162,7 @@
   - name: Ensure location "mylocation" is absent
     ipalocation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: mylocation
       state: absent
     register: result

tests/server/test_server_client_context.yml

+---
+- name: Test server
+  hosts: ipaclients, ipaserver
+  become: no
+  gather_facts: no
+
+  tasks:
+  - name: Include FreeIPA facts.
+    include_tasks: ../env_freeipa_facts.yml
+
+  # Test will only be executed if host is not a server.
+  - name: Execute with server context in the client.
+    ipaserver:
+      ipaadmin_password: SomeADMINpassword
+      ipaapi_context: server
+      name: ThisShouldNotWork
+    register: result
+    failed_when: not (result.failed and result.msg is regex("No module named '*ipaserver'*"))
+    when: ipa_host_is_client
+
+# Import basic module tests, and execute with ipa_context set to 'client'.
+# If ipaclients is set, it will be executed using the client, if not,
+# ipaserver will be used.
+#
+# With this setup, tests can be executed against an IPA client, against
+# an IPA server using "client" context, and ensure that tests are executed
+# in upstream CI.
+
+- name: Test server using client context, in client host.
+  import_playbook: test_server.yml
+  when: groups['ipaclients']
+  vars:
+    ipa_test_host: ipaclients
+
+- name: Test server using client context, in server host.
+  import_playbook: test_server.yml
+  when: groups['ipaclients'] is not defined or not groups['ipaclients']