Fix hostname support

pychromecast/dial.py

@@ -4,7 +4,10 @@
 
 from __future__ import annotations
 
+from collections.abc import Generator
+from contextlib import contextmanager
 from dataclasses import dataclass
+from http import HTTPStatus
 import json
 import logging
 import socket
@@ -74,6 +77,31 @@ def _get_host_from_zc_service_info(
     return (host, port)
 
 
+@contextmanager
+def _urlopen(
+    url: str, timeout: float, context: ssl.SSLContext | None
+) -> Generator[Any, None, None]:
+    """Help open an URL."""
+    headers = {"content-type": "application/json"}
+    try:
+        req = urllib.request.Request(url, headers=headers)
+        yield urllib.request.urlopen(req, timeout=timeout, context=context)
+    except urllib.error.HTTPError as err:
+        if err.code != HTTPStatus.FORBIDDEN:
+            raise
+        # We may be blocked because we're connecting to a hostname specified directly
+        # instead of to an IP address resolved by mDNS, cast devices will reject the
+        # request when the address is set to the hostname. Do another attempt with an
+        # empty host header.
+        # Note: This is a simplified approach to not have to deal with name resolution
+        # in pychromecast. If devices reject the empty host header we need to do name
+        # resolution and instead set the host header to the string version of the IP.
+        _LOGGER.debug("Failed to fetch %s, retrying with empty host header", url)
+        headers["host"] = ""
+        req = urllib.request.Request(url, headers=headers)
+        yield urllib.request.urlopen(req, timeout=timeout, context=context)
+
+
 def _get_status(
     services: set[HostServiceInfo | MDNSServiceInfo],
     zconf: zeroconf.Zeroconf | None,
@@ -101,8 +129,7 @@ def _get_status(
     if secure and not has_context:
         context = get_ssl_context()
 
-    req = urllib.request.Request(url, headers=headers)
-    with urllib.request.urlopen(req, timeout=timeout, context=context) as response:
+    with _urlopen(url, timeout, context) as response:
         data = response.read()
     return (host, json.loads(data.decode("utf-8")))
 
@@ -246,7 +273,8 @@ def get_device_info(  # pylint: disable=too-many-locals
             multizone_supported,
         )
 
-    except (urllib.error.HTTPError, urllib.error.URLError, OSError, ValueError):
+    except (urllib.error.HTTPError, urllib.error.URLError, OSError, ValueError) as err:
+        _LOGGER.debug("Failed to get device info for %s: %s (%s)", host, err, type(err))
         return None
 
 
@@ -305,7 +333,10 @@ def get_multizone_status(
 
         return MultizoneStatus(dynamic_groups, groups)
 
-    except (urllib.error.HTTPError, urllib.error.URLError, OSError, ValueError):
+    except (urllib.error.HTTPError, urllib.error.URLError, OSError, ValueError) as err:
+        _LOGGER.debug(
+            "Failed to get multizone status for %s: %s (%s)", host, err, type(err)
+        )
         return None