[validate-dns] print the error if an unknown error occurs,

so that the script doesn't completely exit upon such errors
- add warning after summary if at least one 'error' occured
- align line beginnings

validate-my-dns.py

@@ -249,6 +249,19 @@ def get_domain_by_mntner(mntner):
     return domains
 
 
+# if an unknown error occurs: notify the user
+def _handle_unknown_error(e: Exception, nserver: str, domain_name: str):
+    global errors
+    print(f"-----------------")
+    print(f"Error: unknown/unexpected error occured while querying  {nserver} for {domain_name}")
+    print(f"Error: '{e.__class__.__module__}.{e.__class__.__name__}': '{str(e)}'")
+    print(f"Note:  please check your nameserver, your network and any related configuration")
+    print(f"-----------------")
+    errors += 1
+    time.sleep(3)
+    return False
+
+
 def get_soa(domain_name, nserver):
     """query dns server for SOA"""
     global errors, summary
@@ -270,11 +283,7 @@ def get_soa(domain_name, nserver):
         summary[domain_name][SUMMARY.SERVFAIL] += 1
         return False
     except Exception as e:
-        print(
+        return _handle_unknown_error(e)
-            f"ERROR: unknown error occured while querying {nserver} for {domain_name}: '{e}'")
-        errors += 1
-        time.sleep(3)
-        return False
         # raise e
     if response[0].rcode() != 0:
         # HANDLE QUERY FAILED (SERVER ERROR OR NO SOA RECORD)
@@ -330,6 +339,8 @@ def get_ns(domain_name, nserver):
             f"ERROR: server replied with different different ip than requested: error: {e}")
         errors += 1
         return False
+    except Exception as e:
+        return _handle_unknown_error(e, nserver=nserver, domain_name=domain_name)
     if response[0].rcode() != 0:
         # HANDLE QUERY FAILED (SERVER ERROR OR NO NS RECORD)
         print(
@@ -390,6 +401,8 @@ def get_dnskey(domain_name, nserver):
         summary[domain_name][SUMMARY.REFUSED] += 1
         errors += 1
         return False
+    except Exception as e:
+        return _handle_unknown_error(e, nserver=nserver, domain_name=domain_name )
 
     if response[0].rcode() != 0:
         # HANDLE QUERY FAILED (SERVER ERROR OR NO DNSKEY RECORD)
@@ -515,6 +528,9 @@ def check_dnssec(domain_name, domain_data):
                     f"WARN:  querying {nserver} ({nsaddr}) for {domain_name} timed out")
                 summary[domain_name][SUMMARY.TIMEOUT] += 1
                 continue
+            except Exception as e:
+                _handle_unknown_error(e, nserver=f"{nserver} ({nsaddr})", domain_name=domain_name)
+                continue
 
             if no_ds_rdatas:
                 print(
@@ -581,16 +597,9 @@ def main(mntner):
     # get all domains/inet(6)nums of the mntner
     domains = get_domain_by_mntner(mntner=mntner)
 
-    # global _tmp_continue, _tmp_found
-    # _tmp_found = False
-    # _tmp_continue = "10.in-addr.arpa"
     def check_dns(domain_name):
         global errors, summary
-        # global _tmp_found, _tmp_continue
+       
-        # if domain_name == _tmp_continue:
-        #     _tmp_found = True
-        # if not _tmp_found:
-        #     return
         summary[domain_name] = [0, 0, 0, 0, 0, 0, 0, 0]
         # check if the domain doesn't have DS data
         if domains[domain_name]["ds-rdata"] == []:
@@ -736,12 +745,15 @@ def main(mntner):
         if len(_domain) > _max_domain_length:
             _max_domain_length = len(_domain)
 
-    print("\n\nSummary:\n")
+    print("```\n\nSummary:\n")
     print(f"{'domain name'.ljust(_max_domain_length)}  | success | dnssec fail | wrong NS | wrong SOA | NXDOMAIN | REFUSED | SERVFAIL | timeout")
     print(f"-{'-'.rjust(_max_domain_length, '-')     }-|---------|-------------|----------|-----------|----------|---------| -------- | -------")
     for domain in summary:
         print(f" {domain.rjust(1).ljust(_max_domain_length)} | {str(summary[domain][SUMMARY.SUCCESS]).rjust(7)} | {str(summary[domain][SUMMARY.DNSSEC_FAIL]).rjust(11)} | {str(summary[domain][SUMMARY.WRONG_NS]).rjust(8)} | {str(summary[domain][SUMMARY.WRONG_SOA]).rjust(9)} | {str(summary[domain][SUMMARY.NXDOMAIN]).rjust(8)} | {str(summary[domain][SUMMARY.REFUSED]).rjust(7)} | {str(summary[domain][SUMMARY.SERVFAIL]).rjust(8)} | {str(summary[domain][SUMMARY.TIMEOUT]).rjust(7)}")
 
+    print("```\n")
+    if errors > 0:
+        print("WARN:  at least one 'error' occured while checking. check the table and output above")
     # print(summary)