test: flexible wait for serve start (#1996)

Co-authored-by: Thomas Viehmann <[email protected]>

Author: Borda

tests/test_readme.py

@@ -10,6 +10,7 @@
 
 import pytest
 import requests
+from urllib3.exceptions import MaxRetryError
 
 from litgpt.utils import _RunIf
 
@@ -215,14 +216,17 @@ def run_server():
     server_thread = threading.Thread(target=run_server)
     server_thread.start()
 
-    # Allow time to initialize and start serving
-    time.sleep(30)
-
-    try:
-        response = requests.get("http://127.0.0.1:8000")
-        print(response.status_code)
-        assert response.status_code == 200, "Server did not respond as expected."
-    finally:
-        if process:
-            process.kill()
-        server_thread.join()
+    for _ in range(30):
+        try:
+            response = requests.get("http://127.0.0.1:8000", timeout=1)
+            response_status_code = response.status_code
+        except (MaxRetryError, requests.exceptions.ConnectionError):
+            response_status_code = -1
+        if response_status_code == 200:
+            break
+        time.sleep(1)
+    assert response_status_code == 200, "Server did not respond as expected."
+
+    if process:
+        process.kill()
+    server_thread.join()