DNS: fix CNAME resolving, don't print ssh commands for DNS requests

cmdeploy/src/cmdeploy/cmdeploy.py

@@ -215,8 +215,9 @@ class Out:
         color = "red" if red else ("green" if green else None)
         print(colored(msg, color), file=file)
 
-    def shell_output(self, arg):
-        self(f"[$ {arg}]", file=sys.stderr)
+    def shell_output(self, arg, no_print=False):
+        if not no_print:
+            self(f"[$ {arg}]", file=sys.stderr)
         return subprocess.check_output(arg, shell=True).decode()
 
     def check_call(self, arg, env=None, quiet=False):

cmdeploy/src/cmdeploy/dns.py

@@ -1,3 +1,5 @@
+import ipaddress
+
 import requests
 import importlib
 import subprocess
@@ -10,19 +12,25 @@ class DNS:
         self.session = requests.Session()
         self.out = out
         self.ssh = f"ssh root@{mail_domain}"
-        self.out.shell_output(f"{self.ssh} -- unbound-control flush {mail_domain}")
+        try:
+            self.shell(f"unbound-control flush {mail_domain}")
+        except subprocess.CalledProcessError:
+            pass
+
+    def shell(self, cmd):
+        return self.out.shell_output(f"{self.ssh} -- {cmd}", no_print=True)
 
     def get_ipv4(self):
         cmd = "ip a | grep 'inet ' | grep 'scope global' | grep -oE '[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}' | head -1"
-        return self.out.shell_output(f"{self.ssh} -- {cmd}").strip()
+        return self.shell(cmd).strip()
 
     def get_ipv6(self):
         cmd = "ip a | grep inet6 | grep 'scope global' | sed -e 's#/64 scope global##' | sed -e 's#inet6##'"
-        return self.out.shell_output(f"{self.ssh} -- {cmd}").strip()
+        return self.shell(cmd).strip()
 
     def get(self, typ: str, domain: str) -> str:
         """Get a DNS entry"""
-        dig_result = self.out.shell_output(f"{self.ssh} -- dig {typ} {domain}")
+        dig_result = self.shell(f"dig {typ} {domain}")
         line_num = 0
         for line in dig_result.splitlines():
             line_num += 1
@@ -31,12 +39,13 @@ class DNS:
 
     def resolve(self, domain: str) -> str:
         result = self.get("A", domain)
-        if not result:
+        try:
+            assert ipaddress.ip_address(result).version == 4
+        except ValueError:
             result = self.get("CNAME", domain)
-            if result:
-                result = self.get("A", result[:-1])
-                if not result:
-                    result = self.get("AAAA", domain)
+            return self.resolve(result)
+        except AssertionError:
+            result = self.get("AAAA", domain)
         return result
 
     def check_ptr_record(self, ip: str, mail_domain) -> str: