PYTHON-5429 Server command is case sensitive

doc/changelog.rst

@@ -10,9 +10,12 @@ PyMongo 4.14 brings a number of changes including:
 - Added :meth:`pymongo.asynchronous.mongo_client.AsyncMongoClient.append_metadata` and
   :meth:`pymongo.mongo_client.MongoClient.append_metadata` to allow instantiated MongoClients to send client metadata
   on-demand
-
 - Introduces a minor breaking change. When encoding :class:`bson.binary.BinaryVector`, a ``ValueError`` will be raised
   if the 'padding' metadata field is < 0 or > 7, or non-zero for any type other than PACKED_BIT.
+- Fixed a bug that raised ``EncryptionError`` when using :meth:`pymongo.mongo_client.MongoClient.server_info` with an
+  encrypted connection. :meth:`pymongo.mongo_client.MongoClient.server_info` now runs the camel cased ``buildInfo`` command
+  instead of the lower cased ``buildinfo`` command which may cause a breaking change in applications that rely on matching the
+  lower cased ``buildinfo`` command.
 
 Changes in Version 4.13.2 (2025/06/17)
 --------------------------------------

pymongo/asynchronous/database.py

@@ -834,12 +834,12 @@ async def command(
         Any additional keyword arguments will be added to the final
         command document before it is sent.
 
-        For example, a command like ``{buildinfo: 1}`` can be sent
+        For example, a command like ``{buildInfo: 1}`` can be sent
         using:
 
-        >>> await db.command("buildinfo")
+        >>> await db.command("buildInfo")
         OR
-        >>> await db.command({"buildinfo": 1})
+        >>> await db.command({"buildInfo": 1})
 
         For a command where the value matters, like ``{count:
         collection_name}`` we can do:

pymongo/asynchronous/mongo_client.py

@@ -2311,7 +2311,7 @@ async def server_info(
         return cast(
             dict,
             await self.admin.command(
-                "buildinfo", read_preference=ReadPreference.PRIMARY, session=session
+                "buildInfo", read_preference=ReadPreference.PRIMARY, session=session
             ),
         )
 

pymongo/synchronous/database.py

@@ -834,12 +834,12 @@ def command(
         Any additional keyword arguments will be added to the final
         command document before it is sent.
 
-        For example, a command like ``{buildinfo: 1}`` can be sent
+        For example, a command like ``{buildInfo: 1}`` can be sent
         using:
 
-        >>> db.command("buildinfo")
+        >>> db.command("buildInfo")
         OR
-        >>> db.command({"buildinfo": 1})
+        >>> db.command({"buildInfo": 1})
 
         For a command where the value matters, like ``{count:
         collection_name}`` we can do:

pymongo/synchronous/mongo_client.py

@@ -2303,7 +2303,7 @@ def server_info(self, session: Optional[client_session.ClientSession] = None) ->
         return cast(
             dict,
             self.admin.command(
-                "buildinfo", read_preference=ReadPreference.PRIMARY, session=session
+                "buildInfo", read_preference=ReadPreference.PRIMARY, session=session
             ),
         )
 

test/asynchronous/test_database.py

@@ -412,9 +412,9 @@ async def test_validate_collection_background(self):
     async def test_command(self):
         self.maxDiff = None
         db = self.client.admin
-        first = await db.command("buildinfo")
-        second = await db.command({"buildinfo": 1})
-        third = await db.command("buildinfo", 1)
+        first = await db.command("buildInfo")
+        second = await db.command({"buildInfo": 1})
+        third = await db.command("buildInfo", 1)
         self.assertEqualReply(first, second)
         self.assertEqualReply(second, third)
 

test/mockupdb/test_network_disconnect_primary.py

@@ -70,17 +70,17 @@ def test_network_disconnect_primary(self):
         self.assertEqual(TOPOLOGY_TYPE.ReplicaSetWithPrimary, topology.description.topology_type)
 
         # Open a socket in the application pool (calls ismaster).
-        with going(client.db.command, "buildinfo"):
-            primary.receives("buildinfo").ok()
+        with going(client.db.command, "buildInfo"):
+            primary.receives("buildInfo").ok()
 
         # The primary hangs replying to ismaster.
         ismaster_future = Future()
         primary.autoresponds("ismaster", lambda r: r.ok(ismaster_future.result()))
 
         # Network error on application operation.
         with self.assertRaises(ConnectionFailure):
-            with going(client.db.command, "buildinfo"):
-                primary.receives("buildinfo").hangup()
+            with going(client.db.command, "buildInfo"):
+                primary.receives("buildInfo").hangup()
 
         # Topology type is updated.
         self.assertEqual(TOPOLOGY_TYPE.ReplicaSetNoPrimary, topology.description.topology_type)
@@ -89,9 +89,9 @@ def test_network_disconnect_primary(self):
         ismaster_future.set_result(primary_response)
 
         # Demand a primary.
-        with going(client.db.command, "buildinfo"):
+        with going(client.db.command, "buildInfo"):
             wait_until(lambda: client.primary == primary.address, "rediscover primary")
-            primary.receives("buildinfo").ok()
+            primary.receives("buildInfo").ok()
 
         self.assertEqual(TOPOLOGY_TYPE.ReplicaSetWithPrimary, topology.description.topology_type)
 

test/mockupdb/test_reset_and_request_check.py

@@ -89,8 +89,8 @@ def _test_disconnect(self, operation):
         after = time.time()
 
         # Demand a reconnect.
-        with going(self.client.db.command, "buildinfo"):
-            self.server.receives("buildinfo").ok()
+        with going(self.client.db.command, "buildInfo"):
+            self.server.receives("buildInfo").ok()
 
         last = self.ismaster_time
         self.assertGreaterEqual(last, after, "called ismaster before needed")

test/test_database.py

@@ -407,9 +407,9 @@ def test_validate_collection_background(self):
     def test_command(self):
         self.maxDiff = None
         db = self.client.admin
-        first = db.command("buildinfo")
-        second = db.command({"buildinfo": 1})
-        third = db.command("buildinfo", 1)
+        first = db.command("buildInfo")
+        second = db.command({"buildInfo": 1})
+        third = db.command("buildInfo", 1)
         self.assertEqualReply(first, second)
         self.assertEqualReply(second, third)