LightOS: update discovery client configuration

The LightOS connector uses hardcoded values for discovery client
connection parameters, preventing customization for different
deployment environments and containers with custom networks.

Example of when this is needed:
We have 1 Cinder instance in a Docker container with network 10.10.10.1,
and a discovery-service located at 10.10.10.2.
In the same cluster, we have a Nova instance in a container with
network 20.20.20.1, and a discovery-service at 20.20.20.2.
I need to be able to set the network address for each instance.

Default values are set for backward compatibility.

Change-Id: I19065ad683b9ff8174814d6e8c500178c885bee4
Signed-off-by: yuval <yuval@lightbitslabs.com>

os_brick/initiator/connectors/lightos.py

@@ -23,6 +23,7 @@ import time
 import traceback
 
 from oslo_concurrency import processutils as putils
+from oslo_config import cfg
 from oslo_log import log as logging
 from oslo_utils import netutils
 import psutil
@@ -35,12 +36,30 @@ from os_brick import utils
 
 
 DEVICE_SCAN_ATTEMPTS_DEFAULT = 5
-DISCOVERY_CLIENT_PORT = 6060
 LOG = logging.getLogger(__name__)
 
 nvmec_pattern = ".*nvme[0-9]+[cp][0-9]+.*"
 nvmec_match = re.compile(nvmec_pattern)
 
+_opts = [
+    cfg.HostAddressOpt('lightos_discovery_client_address',
+                       default="localhost",
+                       help="Address of the LightOS discovery client"),
+    cfg.PortOpt('lightos_discovery_client_port',
+                default=6060,
+                help="Port of the LightOS discovery client"),
+    cfg.StrOpt('lightos_discovery_client_dir_path',
+               default='/etc/discovery-client/discovery.d/',
+               help="Directory path for the LightOS discovery client files.")
+]
+
+cfg.CONF.register_opts(_opts, group='os_brick')
+
+
+def list_opts():
+    """oslo.config.opts entrypoint for sample config generation."""
+    return [('os_brick', _opts)]
+
 
 class LightOSConnector(base.BaseLinuxConnector):
     """Connector class to attach/detach LightOS volumes using NVMe/TCP."""
@@ -62,7 +81,15 @@ class LightOSConnector(base.BaseLinuxConnector):
             device_scan_attempts=device_scan_attempts,
             *args, **kwargs)
         self.message_queue = message_queue
-        self.DISCOVERY_DIR_PATH = '/etc/discovery-client/discovery.d/'
+        self.discovery_dir_path = (
+            cfg.CONF.os_brick.lightos_discovery_client_dir_path
+        )
+        self.discovery_address = (
+            cfg.CONF.os_brick.lightos_discovery_client_address
+        )
+        self.discovery_port = (
+            cfg.CONF.os_brick.lightos_discovery_client_port
+        )
 
     @staticmethod
     def get_ip_addresses():
@@ -123,10 +150,12 @@ class LightOSConnector(base.BaseLinuxConnector):
         return props
 
     def dsc_file_name(self, uuid):
-        return os.path.join(self.DISCOVERY_DIR_PATH, "%s.conf" % uuid)
+        return os.path.join(self.discovery_dir_path, "%s.conf" % uuid)
 
     def find_dsc(self):
-        conn = http.client.HTTPConnection("localhost", DISCOVERY_CLIENT_PORT)
+        conn = http.client.HTTPConnection(
+            self.discovery_address,
+            self.discovery_port)
         try:
             conn.request("HEAD", "/metrics")
             resp = conn.getresponse()

releasenotes/notes/add-lightos-discovery-client-conf-1a1a5b5a68b5914b.yaml

@@ -0,0 +1,28 @@
+---
+features:
+  - |
+    **LightOS connector**: Introduce new configuration options to customize
+    the LightOS discovery client’s behavior.
+
+    Operators can now override the default values for:
+
+    - ``discovery_client_address``
+    - ``discovery_client_port``
+    - ``discovery_client_dir_path``
+
+    These settings allow fine-tuning of the discovery client’s network
+    endpoint and configuration directory.
+
+upgrade:
+  - |
+    **LightOS connector**: Introduce new configuration options to customize
+    the LightOS discovery client’s behavior.
+
+    Operators can now override the default values for:
+
+    - ``discovery_client_address``
+    - ``discovery_client_port``
+    - ``discovery_client_dir_path``
+
+    No changes required. Default values are retained for backward compatibility;
+    no action is needed during upgrade.

setup.cfg

@@ -30,6 +30,7 @@ data_files =
 [entry_points]
 oslo.config.opts =
     os_brick = os_brick.opts:list_opts
+    os_brick.lightos = os_brick.initiator.connectors.lightos:list_opts
 oslo.config.opts.defaults =
     os_brick = os_brick.opts:set_defaults