wlb: T9472: report the initial state of every interface

On start the health daemon forces a state change so the hook learns the
initial state of the WAN interfaces. The flag doing so was reset after the
first interface, every other interface was only reported once its state
actually changed.

The flag is now reset after all interfaces have been checked. The existing
hook smoketest relied on the old behaviour: it now keeps all hook events
and no longer reads a file left over from an earlier run.

2 files changed, 37 insertions, 2 deletions

diff --git a/smoketest/scripts/cli/test_load-balancing_wan.py b/smoketest/scripts/cli/test_load-balancing_wan.py
index ed3970abc..5c67778e3 100755
--- a/smoketest/scripts/cli/test_load-balancing_wan.py
+++ b/smoketest/scripts/cli/test_load-balancing_wan.py
@@ -390,9 +390,13 @@ class TestLoadBalancingWan(VyOSUnitTestSHIM.TestCase):
 ifname=$WLB_INTERFACE_NAME
 state=$WLB_INTERFACE_STATE
 
-echo "$ifname - $state" > {hook_output_path}
+echo "$ifname - $state" >> {hook_output_path}
 """
 
+        # the hook reports every interface on start, keep all events and
+        # drop the ones of earlier runs
+        call(f'sudo rm -f {hook_output_path}')
+        self.addCleanup(call, f'sudo rm -f {hook_output_path} {hook_path}')
         write_file(hook_path, hook_script)
         chmod_755(hook_path)
 
@@ -848,6 +852,35 @@ printf 'WLB_INTERFACE_NAME=%s WLB_SCRIPT_IFACE=%s\\n' \\
         self.cli_set(test + ['ttl-limit', '3'])
         self.cli_commit()
         self.lab_wait_status(failed)
+    def test_hook_initial_state_all_interfaces(self):
+        # the initial state was only reported to the hook for the first
+        # interface
+        tmpdir = tempfile.TemporaryDirectory()
+        self.addCleanup(tmpdir.cleanup)
+        hook = os.path.join(tmpdir.name, 'hook.sh')
+        log = os.path.join(tmpdir.name, 'hook.log')
+        # the hook runs without PATH
+        write_file(hook, f'#!/bin/sh\n/bin/echo "$WLB_INTERFACE_NAME $WLB_INTERFACE_STATE" >> {log}\n')
+        chmod_755(hook)
+        chmod_755(tmpdir.name)
+
+        isps = ['eth231', 'eth232']
+        self.lab_setup('eth230', isps)
+        for index, ifname in enumerate(isps, start=1):
+            self.lab_health(ifname, index)
+            self.cli_set(base_path + ['wan', 'rule', '10', 'interface', ifname])
+        self.cli_set(base_path + ['wan', 'rule', '10', 'inbound-interface', 'eth230'])
+        self.cli_set(base_path + ['wan', 'hook', hook])
+        self.cli_commit()
+
+        def reported():
+            if not os.path.exists(log):
+                return set()
+            with open(log) as f:
+                return set(f.read().splitlines())
+
+        found, last = self.wait_for_result(reported, {'eth231 ACTIVE', 'eth232 ACTIVE'}, timeout=20)
+        self.assertTrue(found, msg=f'hook reported {last}')
 
 if __name__ == '__main__':
     unittest.main(verbosity=2, failfast=VyOSUnitTestSHIM.TestCase.debug_on())
diff --git a/src/helpers/vyos-load-balancer.py b/src/helpers/vyos-load-balancer.py
index d289f1c7f..38ba8d87b 100755
--- a/src/helpers/vyos-load-balancer.py
+++ b/src/helpers/vyos-load-balancer.py
@@ -375,7 +375,6 @@ if __name__ == '__main__':
                     #Force state changed to trigger the first write
                     if init == True:
                         state['state_changed'] = True
-                        init = False
 
                     if state['state_changed']:
                         state['if_addr'] = get_ipv4_address(ifname)
@@ -386,6 +385,9 @@ if __name__ == '__main__':
 
                     restore_default_route(lb, ifname)
 
+            # every interface reports its initial state
+            init = False
+
             if any(state['state_changed'] for ifname, state in lb['health_state'].items()):
                 if not nftables_update(lb):
                     break