Make LLDP OVS agent driver more robust to json output

An issue was seen recently in which a bridge with a single port caused
an exception in the LLDP driver, as the json output did not match what
was expected.  In this case, the port was a simple uuid/value list
rather than a list of uuid/value lists.

ie.

["br-ex",["uuid","val1"]]

vs

["br-int",["set",[["uuid","val2"],["uuid","val3"]]]]

This commit adds a fix to handle  both cases, and also adds
robustness to gracefully catch similar issues of unexpected json
output.

Closes-Bug: #1802118
Change-Id: I73189f138a543f34e467f51e18544b521a00457c
Signed-off-by: Steven Webster <steven.webster@windriver.com>

sysinv/sysinv/sysinv/sysinv/agent/lldp/drivers/ovs/driver.py

@@ -46,8 +46,12 @@ class SysinvOVSAgentDriver(lldpd_driver.SysinvLldpdAgentDriver):
         ports = ports['data']
 
         for port in ports:
-            port_uuid = port[1][1]
+            try:
-            interfaces = port[2][1]
+                port_uuid = port[1][1]
+                interfaces = port[2][1]
+            except IndexError:
+                LOG.error("Unexpected port in LLDP port list: %r", port)
+                continue
 
             if isinstance(interfaces, list):
                 for interface in interfaces:
@@ -72,11 +76,25 @@ class SysinvOVSAgentDriver(lldpd_driver.SysinvLldpdAgentDriver):
         bridges = bridges['data']
 
         for bridge in bridges:
-            bridge_name = bridge[0]
+            try:
-            port_set = bridge[1][1]
+                bridge_name = bridge[0]
-            for port in port_set:
+                ports = bridge[1][1]
-                value = port[1]
+            except IndexError:
-                port_bridge_map[value] = bridge_name
+                LOG.error("Unexpected bridge in LLDP bridge list: %r", bridge)
+                continue
+
+            if isinstance(ports, list):
+                for port in ports:
+                    try:
+                        port_uuid = port[1]
+                    except IndexError:
+                        LOG.error("Unexpected port in LLDP bridge list: %r",
+                                  port)
+                        continue
+                    port_bridge_map[port_uuid] = bridge_name
+            else:
+                port_uuid = ports
+                port_bridge_map[port_uuid] = bridge_name
 
         return port_bridge_map
 
@@ -94,17 +112,17 @@ class SysinvOVSAgentDriver(lldpd_driver.SysinvLldpdAgentDriver):
     def lldp_ovs_add_flows(self, brname, in_port, out_port):
 
         cmd = ("ovs-ofctl add-flow {} in_port={},dl_dst={},dl_type={},"
-               "actions=output:{}".format(
+               "actions=output:{}".format(brname, in_port,
-                    brname, in_port, constants.LLDP_MULTICAST_ADDRESS,
+                                          constants.LLDP_MULTICAST_ADDRESS,
-                    constants.LLDP_ETHER_TYPE, out_port))
+                                          constants.LLDP_ETHER_TYPE, out_port))
         output = self.run_cmd(cmd)
         if not output:
             return
 
         cmd = ("ovs-ofctl add-flow {} in_port={},dl_dst={},dl_type={},"
-               "actions=output:{}".format(
+               "actions=output:{}".format(brname, out_port,
-                    brname, out_port, constants.LLDP_MULTICAST_ADDRESS,
+                                          constants.LLDP_MULTICAST_ADDRESS,
-                    constants.LLDP_ETHER_TYPE, in_port))
+                                          constants.LLDP_ETHER_TYPE, in_port))
         output = self.run_cmd(cmd)
         if not output:
             return
@@ -130,29 +148,53 @@ class SysinvOVSAgentDriver(lldpd_driver.SysinvLldpdAgentDriver):
         data = data['data']
 
         for interface in data:
-            name = interface[0]
+            try:
-            uuid = interface[1][1]
+                name = interface[0]
-            type = interface[2]
+                uuid = interface[1][1]
-            other_config = interface[3]
+                type = interface[2]
+                other_config = interface[3]
+            except IndexError:
+                LOG.error("Unexpected interface in LLDP interface list: %r",
+                          interface)
+                continue
 
             if type != 'internal':
                 continue
 
-            config_map = other_config[1]
+            if uuid not in interface_port_map:
+                continue
+
+            if interface_port_map[uuid] not in port_bridge_map:
+                continue
+
+            brname = port_bridge_map[interface_port_map[uuid]]
+
+            try:
+                config_map = other_config[1]
+            except IndexError:
+                LOG.error("Unexpected config map in LLDP interface list: %r",
+                          config_map)
+                continue
+
             for config in config_map:
-                key = config[0]
+                try:
-                value = config[1]
+                    key = config[0]
-                if key != 'lldp_phy_peer':
+                    value = config[1]
+                except IndexError:
+                    LOG.error("Unexpected config in LLDP interface list: %r",
+                              config)
                     continue
 
+                if key != 'lldp_phy_peer':
+                    continue
                 phy_peer = value
-                brname = port_bridge_map[interface_port_map[uuid]]
+
                 if not self.lldp_ovs_lldp_flow_exists(brname, name):
                     LOG.info("Adding missing LLDP flow from %s to %s",
                              name, phy_peer)
                     self.lldp_ovs_add_flows(brname, name, phy_peer)
 
-                if not self.lldp_ovs_lldp_flow_exists(brname, value):
+                if not self.lldp_ovs_lldp_flow_exists(brname, phy_peer):
                     LOG.info("Adding missing LLDP flow from %s to %s",
                              phy_peer, name)
                     self.lldp_ovs_add_flows(brname, phy_peer, name)