daemon: refactored how to get required commands, added usage of this func for validating distributed servers when added

daemon/core/executables.py

@@ -14,3 +14,18 @@ OVS_VSCTL: str = "ovs-vsctl"
 COMMON_REQUIREMENTS: List[str] = [SYSCTL, IP, ETHTOOL, TC, EBTABLES, MOUNT, UMOUNT]
 VCMD_REQUIREMENTS: List[str] = [VNODED, VCMD]
 OVS_REQUIREMENTS: List[str] = [OVS_VSCTL]
+
+
+def get_requirements(use_ovs: bool) -> List[str]:
+    """
+    Retrieve executable requirements needed to run CORE.
+
+    :param use_ovs: True if OVS is being used, False otherwise
+    :return: list of executable requirements
+    """
+    requirements = COMMON_REQUIREMENTS
+    if use_ovs:
+        requirements += OVS_REQUIREMENTS
+    else:
+        requirements += VCMD_REQUIREMENTS
+    return requirements