Improve handling of unresolvable news servers (#2347)

* Trying to find cause of git bug #2345

* Try to find IP using happyeyeballs first, fall back to default if it fails

* Fix mistake

* Add host name to connection error message

* Always debug log IP address

sabnzbd/downloader.py

@@ -178,23 +178,21 @@ def hostip(self) -> str:
         # Determine IP
         ip = self.host
         if self.info:
-            if cfg.load_balancing() == 0 or len(self.info) == 1:
+            # Check this first so we can fall back to default method if it returns None.
+            if len(self.info) > 1 and cfg.load_balancing() == 2:
+                # RFC6555 / Happy Eyeballs:
+                ip = happyeyeballs(self.host, port=self.port)
+                if not ip:
+                    # nothing returned, so there was a connection problem
+                    logging.debug("%s: No successful IP connection was possible using happyeyeballs", self.host)
+            if not ip or cfg.load_balancing() == 0 or len(self.info) == 1:
                 # Just return the first one, so all next threads use the same IP
                 ip = self.info[0][4][0]
-                logging.debug("%s: Connecting to address %s", self.host, ip)
             elif cfg.load_balancing() == 1:
                 # Return a random entry from the possible IPs
                 rnd = random.randint(0, len(self.info) - 1)
                 ip = self.info[rnd][4][0]
-                logging.debug("%s: Connecting to address %s", self.host, ip)
-            elif cfg.load_balancing() == 2:
-                # RFC6555 / Happy Eyeballs:
-                ip = happyeyeballs(self.host, port=self.port)
-                if ip:
-                    logging.debug("%s: Connecting to address %s", self.host, ip)
-                else:
-                    # nothing returned, so there was a connection problem
-                    logging.debug("%s: No successful IP connection was possible", self.host)
+        logging.debug("%s: Connecting to address %s", self.host, ip)
         return ip
 
     def deactivate(self):
@@ -968,7 +966,7 @@ def __reset_nw(
                 nw.article.tries += 1
 
             # Do we discard, or try again for this server
-            if not retry_article or nw.article.tries > cfg.max_art_tries():
+            if not retry_article or (not nw.server.required and nw.article.tries > cfg.max_art_tries()):
                 # Too many tries on this server, consider article missing
                 self.decode(nw.article, None)
                 nw.article.tries = 0

sabnzbd/newswrapper.py

@@ -397,10 +397,13 @@ def error(self, error: OSError):
             raise socket.error(errno.ECONNREFUSED, str(error))
         else:
             msg = "Failed to connect: %s" % (str(error))
-            msg = "%s %s@%s:%s" % (msg, self.nw.thrdnum, self.host, self.nw.server.port)
+            msg = "%s %s:%s (%s)" % (msg, self.nw.server.host, self.nw.server.port, self.host)
             self.error_msg = msg
             self.nw.server.next_busy_threads_check = 0
-            logging.info(msg)
+            if self.nw.server.warning == msg:
+                logging.info(msg)
+            else:
+                logging.warning(msg)
             self.nw.server.warning = msg
 
     def __repr__(self):