Merge ~pwlars/plainbox-provider-checkbox:discover-gateway-ip into plainbox-provider-checkbox:master

[Paul Larson]

Same concept as my previous MP, but do it in gateway_ping_test instead. We can still rely on the arp mechanism to find the address, but we can't depend on broadcast ping to get the router into the arp table. Instead, try to help it along by finding the address of the gateway and pinging it.

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I noticed that dawson-j was consistently failing on the wifi tests today, so I took the opportunity to look into it a bit more. The gateway ping test can take an arg to tell it which ip you want it to ping, but we don't pass it that, instead we rely on it to discover a valid ip for the subnet using a broadcast ping, followed by looking at the arp table. However, if nothing replies to the broadcast ping, it doesn't discover any valid ip and has nothing to ping. If I gave it a valid ip to ping, or even pinged the gateway so that it would arp, then it worked just fine though.

I tried this patch on that system, and it worked after that.

[Sylvain Pineau (sylvain-pineau)]

LGTM, +1

review: Approve

[Jonathan Cave (jocave)]

Thanks for extra tests on NM managed devices, LGTM

review: Approve

diff --git a/bin/gateway_ping_test b/bin/gateway_ping_test
index 914792c..7bac0f8 100755
--- a/bin/gateway_ping_test
+++ b/bin/gateway_ping_test
@@ -133,6 +133,18 @@ def get_host_to_ping(interface=None, verbose=False, default=None):
                                     stderr=subprocess.STDOUT)
         except subprocess.CalledProcessError:
             pass
+    # Try to get the gateway address for the interface from networkctl
+    cmd = 'networkctl status --no-pager --no-legend {}'.format(interface)
+    try:
+        output = subprocess.check_output(cmd, shell=True)
+        for line in output.decode(sys.stdout.encoding).splitlines():
+            key, val = line.strip().split(':', maxsplit=1)
+            if key == "Gateway":
+                subprocess.check_output(["ping", "-q", "-c", "1", val],
+                                        stderr=subprocess.STDOUT)
+                break
+    except subprocess.CalledProcessError:
+        pass
     ARP_POPULATE_TRIES = 10
     num_tries = 0
     while num_tries < ARP_POPULATE_TRIES: