Fix 1716 - Retry on mirror list fetching (#2736)

* Fix 1716 - retry on http calls

* Update

* Update

archinstall/lib/mirrors.py

@@ -1,3 +1,4 @@
+import time
 import json
 import pathlib
 from dataclasses import dataclass, field
@@ -6,7 +7,7 @@ from typing import Dict, Any, List, Optional, TYPE_CHECKING
 
 from .menu import AbstractSubMenu, Selector, MenuSelectionType, Menu, ListManager, TextInput
 from .networking import fetch_data_from_url
-from .output import warn, FormattedOutput
+from .output import FormattedOutput, debug
 from .storage import storage
 from .models.mirrors import MirrorStatusListV3, MirrorStatusEntryV3
 
@@ -324,17 +325,22 @@ def _parse_mirror_list(mirrorlist: str) -> Dict[str, List[MirrorStatusEntryV3]]:
 
 
 def list_mirrors() -> Dict[str, List[MirrorStatusEntryV3]]:
-	regions: Dict[str, List[MirrorStatusEntryV3]] = {}
-
-	if storage['arguments']['offline']:
-		with pathlib.Path('/etc/pacman.d/mirrorlist').open('r') as fp:
-			mirrorlist = fp.read()
-	else:
+	if not storage['arguments']['offline']:
 		url = "https://archlinux.org/mirrors/status/json/"
-		try:
-			mirrorlist = fetch_data_from_url(url)
-		except ValueError as err:
-			warn(f'Could not fetch an active mirror-list: {err}')
-			return regions
+		attempts = 3
 
-	return _parse_mirror_list(mirrorlist)
+		for attempt_nr in range(attempts):
+			try:
+				mirrorlist = fetch_data_from_url(url)
+				return _parse_mirror_list(mirrorlist)
+			except Exception as e:
+				debug(f'Error while fetching mirror list: {e}')
+				time.sleep(attempt_nr + 1)
+
+		debug('Unable to fetch mirror list remotely, falling back to local mirror list')
+
+	# we'll use the local mirror list if the offline flag is set
+	# or if fetching the mirror list remotely failed
+	with pathlib.Path('/etc/pacman.d/mirrorlist').open('r') as fp:
+		mirrorlist = fp.read()
+		return _parse_mirror_list(mirrorlist)

archinstall/lib/networking.py

@@ -133,8 +133,10 @@ def fetch_data_from_url(url: str, params: Optional[dict] = None) -> str:
 		response = urlopen(full_url, context=ssl_context)
 		data = response.read().decode('UTF-8')
 		return data
-	except URLError:
-		raise ValueError(f'Unable to fetch data from url: {url}')
+	except URLError as e:
+		raise ValueError(f'Unable to fetch data from url: {url}\n{e}')
+	except Exception as e:
+		raise ValueError(f'Unexpected error when parsing response: {e}')
 
 
 def calc_checksum(icmp_packet) -> int: