Add option to override API endpoint

Provide an option to override API endpoint to address multiple
manila deployments on same cloud. Usage as following:
"openstack --os-endpoint-override <endpoint_url> share list"

Closes-bug: #2111331
Co-authored-by: Chuan Miao <chuan.miao@sap.com>
Change-Id: I5e11256473ab88b08e7374fd68f58a0257adab1f
Signed-off-by: Kiran Pawar <kinpaa@gmail.com>

doc/source/cli/osc_plugin_cli.rst

@@ -31,6 +31,13 @@ environment variables::
     export OS_AUTH_URL=http://...
     export OS_SHARE_API_VERSION=2.51
 
+It is possible to use different Manila endpoint while using Openstack
+Client. In this case, you can use configuration option
+``--os-endpoint-override`` or set the corresponding environment
+variable::
+
+    export OS_ENDPOINT_OVERRIDE=http://...
+
 
 Getting help
 ============

manilaclient/osc/plugin.py

@@ -113,4 +113,17 @@ def build_option_parser(parser):
              'version supported by both the client and the server). '
              '(Env: OS_SHARE_API_VERSION)',
     )
+    parser.add_argument(
+        "--os-endpoint-override",
+        metavar="<endpoint-override>",
+        default=utils.env(
+            "OS_ENDPOINT_OVERRIDE",
+            "OS_MANILA_BYPASS_URL",
+            "MANILACLIENT_BYPASS_URL",
+        ),
+        help=(
+            "Use this API endpoint instead of the Service Catalog. "
+            "Defaults to env[OS_ENDPOINT_OVERRIDE]."
+        ),
+    )
     return parser

releasenotes/notes/add-support-of-api-endpoint-override-e36e75246d39a367.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - Manilaclient is updated to consider API endpoint override option
+    `--os-endpoint-override`. For example, "openstack share list" command
+    for different API endpoint will be "openstack --os-endpoint-override
+    <endpoint_url> share list".