parse systemd-resolve output

tests/test_dns_records.py

@@ -6,6 +6,7 @@ Checks that DNS records are provided by the customer servers are correctly set
 """
 
 from pathlib import Path
+import re
 import subprocess
 import sys
 
@@ -16,15 +17,33 @@ from envsetup import utils as u  # noqa: E402
 
 
 def get_dns_servers() -> set:
-    with open("/etc/resolv.conf", "r") as f:
-        d = f.read().strip()
-        servers = [l.split()[1] for l in d.split("\n") if l.startswith("nameserver")]
-    if len(servers) and servers[0].startswith("127.0."):
-        # network-manager or systemd-resolved
+    if subprocess.getstatusoutput("command -v nmcli")[0] == 0:
+        # network-manager
         _, output = subprocess.getstatusoutput(
             "nmcli -f all device show | grep IP4.DNS | awk '{ print $2 }'"
         )
         servers = output.split("\n")
+    else:
+        # resolvconf
+        with open("/etc/resolv.conf", "r") as f:
+            d = f.read().strip()
+            servers = [l.split()[1] for l in d.split("\n") if l.startswith("nameserver")]
+
+    if "127.0.0.53" in servers:
+        # systemd-resolved
+        _, output = subprocess.getstatusoutput("systemd-resolve --status")
+        lines = [l.strip() for l in output.split("\n")]
+        dns_line = False
+        ip_pattern = re.compile("\d+\.\d+\.\d+\.\d+")
+        for line in lines:
+            if line.startswith("DNS Servers:"):
+                dns_line = True
+                servers.append(line.split()[-1])
+            elif dns_line and ip_pattern.match(line):
+                servers.append(line)
+            else:
+                dns_line = False
+
 
     return set(servers)