bug 1894925: add handling for TimeoutError

This adds handling for TimeoutError so it'll go through the loop again.
It increases the blocking timeout to 2 which is slightly longer than 1s.
It also changes everything to f-strings.

The theory is that in CI, it's taking longer than 1s for localstack to
respond sometimes which causes CI to fail and because the loop didn't
handle TimeoutError, it would die immediately.

bin/waitfor.py

@@ -12,7 +12,6 @@
 """
 
 import argparse
-import socket
 import urllib.error
 import urllib.request
 from urllib.parse import urlsplit
@@ -49,34 +48,32 @@ def main(args):
         url = parsed_url.geturl()
 
     if parsed.verbose:
-        print(
-            "Testing %s for %s with timeout %d..."
-            % (url, repr(ok_codes), parsed.timeout)
-        )
-
-    socket.setdefaulttimeout(1)
+        print(f"Testing {url} for {ok_codes!r} with timeout {parsed.timeout}...")
 
     start_time = time.time()
 
     last_fail = ""
     while True:
         try:
-            with urllib.request.urlopen(url) as resp:
+            with urllib.request.urlopen(url, timeout=5) as resp:
                 if resp.code in ok_codes:
                     sys.exit(0)
-                last_fail = "HTTP status code: %s" % resp.code
+                last_fail = f"HTTP status code: {resp.code}"
+        except TimeoutError as error:
+            last_fail = f"TimeoutError: {error}"
         except urllib.error.URLError as error:
             if hasattr(error, "code") and error.code in ok_codes:
                 sys.exit(0)
-            last_fail = "URLError: %s" % error
+            last_fail = f"URLError: {error}"
 
         if parsed.verbose:
             print(last_fail)
 
-        time.sleep(1)
+        time.sleep(0.5)
 
-        if time.time() - start_time > parsed.timeout:
-            print("Failed. %s" % last_fail)
+        delta = time.time() - start_time
+        if delta > parsed.timeout:
+            print(f"Failed: {last_fail}, elapsed: {delta:.2f}s")
             sys.exit(1)