fixup: issues on IPv4-only machines

src/func_python/cloudevent.py

@@ -2,6 +2,7 @@
 import logging
 import os
 import signal
+import socket
 import hypercorn.config
 import hypercorn.asyncio
 
@@ -74,7 +75,13 @@ def serve(self):
         """serve serving this ASGIhandler, delegating implementation of
            methods as necessary to the wrapped Function instance"""
         cfg = hypercorn.config.Config()
-        cfg.bind = [os.getenv('LISTEN_ADDRESS', DEFAULT_LISTEN_ADDRESS)]
+
+        la = os.getenv('LISTEN_ADDRESS', DEFAULT_LISTEN_ADDRESS)
+        [host, port] = la.rsplit(":", 1)
+        # fixup for IPv4-only machines
+        if not socket.has_ipv6 and host == '[::]':
+            la = "0.0.0.0:" + port
+        cfg.bind = [la]
 
         logging.info(f"function starting on {cfg.bind}")
         return asyncio.run(self._serve(cfg))

src/func_python/http.py

@@ -3,6 +3,7 @@
 import logging
 import os
 import signal
+import socket
 import hypercorn.config
 import hypercorn.asyncio
 
@@ -69,7 +70,13 @@ def serve(self):
         """serve serving this ASGIhandler, delegating implementation of
            methods as necessary to the wrapped Function instance"""
         cfg = hypercorn.config.Config()
-        cfg.bind = [os.getenv('LISTEN_ADDRESS', DEFAULT_LISTEN_ADDRESS)]
+
+        la = os.getenv('LISTEN_ADDRESS', DEFAULT_LISTEN_ADDRESS)
+        [host, port] = la.rsplit(":", 1)
+        # fixup for IPv4-only machines
+        if not socket.has_ipv6 and host == '[::]':
+            la = "0.0.0.0:" + port
+        cfg.bind = [la]
 
         logging.debug(f"function starting on {cfg.bind}")
         return asyncio.run(self._serve(cfg))