Fix: Fail early when database server does not respond

Author: amotl

CHANGES.rst

@@ -5,6 +5,9 @@ Changes for crate
 Unreleased
 ==========
 
+- Changed connection behaviour to fail early when database server
+  does not respond
+
 2025/01/30 2.0.0
 ================
 

src/crate/client/connection.py

@@ -20,6 +20,7 @@
 # software solely pursuant to the terms of the relevant commercial agreement.
 
 from verlib2 import Version
+from verlib2.packaging.version import InvalidVersion
 
 from .blob import BlobContainer
 from .cursor import Cursor
@@ -197,14 +198,20 @@ def get_blob_container(self, container_name):
 
     def _lowest_server_version(self):
         lowest = None
+        last_connection_error = None
         for server in self.client.active_servers:
             try:
                 _, _, version = self.client.server_infos(server)
                 version = Version(version)
-            except (ValueError, ConnectionError):
+            except ConnectionError as ex:
+                last_connection_error = ex
+                continue
+            except (ValueError, InvalidVersion):
                 continue
             if not lowest or version < lowest:
                 lowest = version
+        if lowest is None and last_connection_error is not None:
+            raise last_connection_error
         return lowest or Version("0.0.0")
 
     def __repr__(self):

tests/client/test_connection.py

@@ -3,6 +3,7 @@
 
 from urllib3 import Timeout
 
+import crate.client.exceptions
 from crate.client import connect
 from crate.client.connection import Connection
 from crate.client.http import Client
@@ -36,6 +37,12 @@ def server_infos(self, server):
             ("localhost:4200", "my server", "0.42.0"),
         )
 
+    def test_invalid_server_address(self):
+        client = Client(servers="localhost:4202")
+        with self.assertRaises(crate.client.exceptions.ConnectionError) as ex:
+            connect(client=client)
+        self.assertIn("Server not available", ex.exception.message)
+
     def test_lowest_server_version(self):
         infos = [
             (None, None, "0.42.3"),