ipavault: Allow execution of plugin in client host.

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

A new test playbook can be found at:

    tests/vault/test_vault_client_context.yml

As `ipavault` only works in client context, an error is raised if it
is explicitly executed in a server context.

tests/vault/env_cleanup.yml

@@ -26,6 +26,7 @@
   - name: Ensure test users do not exist.
     ipauser:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name:
       - user01
       - user02
@@ -35,6 +36,7 @@
   - name: Ensure test groups do not exist.
     ipagroup:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: vaultgroup
       state: absent
 

tests/vault/env_setup.yml

@@ -35,11 +35,13 @@
   - name: Ensure vaultgroup exists.
     ipagroup:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: vaultgroup
 
   - name: Ensure testing users exist.
     ipauser:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       users:
       - name: user01
         first: First

tests/vault/test_vault_client_context.yml

@@ -0,0 +1,25 @@
+---
+- name: Test vault
+  hosts: ipaserver
+  become: no
+  # Need to gather facts for ansible_env.
+  gather_facts: yes
+
+  tasks:
+  - name: Setup testing environment.
+    import_tasks: env_setup.yml
+
+  # vault requires 'ipaapi_context: client', and uses this
+  # context by defoult, so we test only for the case where
+  # 'ipaapi_context: server' is explicitly set.
+  - name: Execute with server context.
+    ipavault:
+      ipaadmin_password: SomeADMINpassword
+      ipaapi_context: server
+      name: ThisShouldNotWork
+      vault_type: standard
+    register: result
+    failed_when: not (result.failed and result.msg is regex("Context 'server' for ipavault not yet supported."))
+
+  - name: Cleanup testing environment.
+    import_tasks: env_cleanup.yml