PYTHON-4729 Drop support for MongoDB 3.6 (mongodb#1905)

Author: ShaneHarvey

.evergreen/config.yml

@@ -1014,33 +1014,6 @@ tasks:
             TOPOLOGY: "server"
         - func: "run doctests"
 
-    - name: "test-3.6-standalone"
-      tags: ["3.6", "standalone"]
-      commands:
-        - func: "bootstrap mongo-orchestration"
-          vars:
-            VERSION: "3.6"
-            TOPOLOGY: "server"
-        - func: "run tests"
-
-    - name: "test-3.6-replica_set"
-      tags: ["3.6", "replica_set"]
-      commands:
-        - func: "bootstrap mongo-orchestration"
-          vars:
-            VERSION: "3.6"
-            TOPOLOGY: "replica_set"
-        - func: "run tests"
-
-    - name: "test-3.6-sharded_cluster"
-      tags: ["3.6", "sharded_cluster"]
-      commands:
-        - func: "bootstrap mongo-orchestration"
-          vars:
-            VERSION: "3.6"
-            TOPOLOGY: "sharded_cluster"
-        - func: "run tests"
-
     - name: "test-4.0-standalone"
       tags: ["4.0", "standalone"]
       commands:
@@ -2186,10 +2159,6 @@ axes:
   - id: mongodb-version
     display_name: "MongoDB"
     values:
-      - id: "3.6"
-        display_name: "MongoDB 3.6"
-        variables:
-          VERSION: "3.6"
       - id: "4.0"
         display_name: "MongoDB 4.0"
         variables:
@@ -2490,7 +2459,6 @@ buildvariants:
     - ".4.4"
     - ".4.2"
     - ".4.0"
-    - ".3.6"
 
 - matrix_name: "test-macos-arm64"
   matrix_spec:
@@ -2562,7 +2530,6 @@ buildvariants:
     - ".4.4"
     - ".4.2"
     - ".4.0"
-    - ".3.6"
 
 - matrix_name: "tests-pyopenssl"
   matrix_spec:
@@ -2657,19 +2624,22 @@ buildvariants:
   display_name: "${compression} ${c-extensions} ${python-version} ${platform}"
   tasks:
     - "test-latest-standalone"
+    - "test-8.0-standalone"
+    - "test-7.0-standalone"
+    - "test-6.0-standalone"
     - "test-5.0-standalone"
     - "test-4.4-standalone"
     - "test-4.2-standalone"
+    - "test-4.0-standalone"
   rules:
-    # Server versions 3.6 and 4.0 support snappy and zlib.
+    # Server version 4.0 supports snappy and zlib but not zstd.
     - if:
         python-version: "*"
         c-extensions: "*"
-        compression: ["snappy", "zlib"]
+        compression: ["zstd"]
       then:
-        add_tasks:
+        remove_tasks:
           - "test-4.0-standalone"
-          - "test-3.6-standalone"
 
 - matrix_name: "tests-python-version-green-framework-rhel8"
   matrix_spec:
@@ -2734,7 +2704,7 @@ buildvariants:
   matrix_spec:
     platform: rhel8
     storage-engine: "*"
-    python-version: 3.9
+    python-version: "3.9"
   display_name: "Storage ${storage-engine} ${python-version} ${platform}"
   rules:
     - if:
@@ -2751,7 +2721,6 @@ buildvariants:
           - "test-4.4-standalone"
           - "test-4.2-standalone"
           - "test-4.0-standalone"
-          - "test-3.6-standalone"
     - if:
         # MongoDB 4.2 drops support for MMAPv1
         platform: rhel8
@@ -2761,8 +2730,6 @@ buildvariants:
         add_tasks:
           - "test-4.0-standalone"
           - "test-4.0-replica_set"
-          - "test-3.6-standalone"
-          - "test-3.6-replica_set"
 
 # enableTestCommands=0 tests on RHEL 8.4 (x86_64) with Python 3.9.
 - matrix_name: "test-disableTestCommands"
@@ -2881,6 +2848,9 @@ buildvariants:
   tasks:
     # Versioned API was introduced in MongoDB 4.7
     - "test-latest-standalone"
+    - "test-8.0-standalone"
+    - "test-7.0-standalone"
+    - "test-6.0-standalone"
     - "test-5.0-standalone"
 
 - matrix_name: "ocsp-test"

README.md

@@ -14,7 +14,7 @@ a native Python driver for MongoDB. The `gridfs` package is a
 [gridfs](https://github.com/mongodb/specifications/blob/master/source/gridfs/gridfs-spec.rst/)
 implementation on top of `pymongo`.
 
-PyMongo supports MongoDB 3.6, 4.0, 4.2, 4.4, 5.0, 6.0, 7.0, and 8.0.
+PyMongo supports MongoDB 4.0, 4.2, 4.4, 5.0, 6.0, 7.0, and 8.0.
 
 ## Support / Feedback
 

doc/changelog.rst

@@ -5,6 +5,21 @@ Changes in Version 4.11.0
 -------------------------
 
 .. warning:: PyMongo 4.11 drops support for Python 3.8: Python 3.9+ or PyPy 3.9+ is now required.
+.. warning:: PyMongo 4.11 drops support for MongoDB 3.6. PyMongo now supports MongoDB 4.0+.
+   Driver support for MongoDB 3.6 reached end of life in April 2024.
+
+PyMongo 4.11 brings a number of changes including:
+
+- Dropped support for Python 3.8.
+- Dropped support for MongoDB 3.6.
+
+Issues Resolved
+...............
+
+See the `PyMongo 4.11 release notes in JIRA`_ for the list of resolved issues
+in this release.
+
+.. _PyMongo 4.11 release notes in JIRA: https://jira.mongodb.org/secure/ReleaseNote.jspa?projectId=10004&version=40784
 
 Changes in Version 4.10.1
 -------------------------

doc/common-issues.rst

@@ -6,14 +6,14 @@ Also see the :ref:`TLSErrors` section.
 Server reports wire version X, PyMongo requires Y
 -------------------------------------------------
 
-When one attempts to connect to a <=3.4 version server, PyMongo will throw the following error::
+When one attempts to connect to a <=3.6 version server, PyMongo will throw the following error::
 
   >>> client.admin.command('ping')
   ...
-  pymongo.errors.ConfigurationError: Server at localhost:27017 reports wire version 5, but this version of PyMongo requires at least 6 (MongoDB 3.6).
+  pymongo.errors.ConfigurationError: Server at localhost:27017 reports wire version 6, but this version of PyMongo requires at least 7 (MongoDB 4.0).
 
 This is caused by the driver being too new for the server it is being run against.
-To resolve this issue either upgrade your database to version >= 3.6 or downgrade to PyMongo 3.x which supports MongoDB >= 2.6.
+To resolve this issue either upgrade your database to version >= 4.0 or downgrade to an early version of PyMongo which supports MongoDB < 4.0.
 
 
 'Cursor' object has no attribute '_Cursor__killed'

doc/examples/authentication.rst

@@ -97,9 +97,8 @@ the "MongoDB Challenge-Response" protocol::
 Default Authentication Mechanism
 --------------------------------
 
-If no mechanism is specified, PyMongo automatically SCRAM-SHA-1 when connected
-to MongoDB 3.6 and negotiates the mechanism to use (SCRAM-SHA-1
-or SCRAM-SHA-256) when connected to MongoDB 4.0+.
+If no mechanism is specified, PyMongo automatically negotiates the mechanism to use (SCRAM-SHA-1
+or SCRAM-SHA-256) with the MongoDB server.
 
 Default Database and "authSource"
 ---------------------------------

pymongo/asynchronous/collection.py

@@ -1960,20 +1960,15 @@ async def _count_cmd(
         collation: Optional[Collation],
     ) -> int:
         """Internal count command helper."""
-        # XXX: "ns missing" checks can be removed when we drop support for
-        # MongoDB 3.0, see SERVER-17051.
         res = await self._command(
             conn,
             cmd,
             read_preference=read_preference,
-            allowable_errors=["ns missing"],
             codec_options=self._write_response_codec_options,
             read_concern=self.read_concern,
             collation=collation,
             session=session,
         )
-        if res.get("errmsg", "") == "ns missing":
-            return 0
         return int(res["n"])
 
     async def _aggregate_one_result(

pymongo/asynchronous/mongo_client.py

@@ -498,9 +498,8 @@ def __init__(
           - `authSource`: The database to authenticate on. Defaults to the
             database specified in the URI, if provided, or to "admin".
           - `authMechanism`: See :data:`~pymongo.auth.MECHANISMS` for options.
-            If no mechanism is specified, PyMongo automatically SCRAM-SHA-1
-            when connected to MongoDB 3.6 and negotiates the mechanism to use
-            (SCRAM-SHA-1 or SCRAM-SHA-256) when connected to MongoDB 4.0+.
+            If no mechanism is specified, PyMongo automatically negotiates the
+            mechanism to use (SCRAM-SHA-1 or SCRAM-SHA-256) with the MongoDB server.
           - `authMechanismProperties`: Used to specify authentication mechanism
             specific options. To specify the service name for GSSAPI
             authentication pass authMechanismProperties='SERVICE_NAME:<service

pymongo/common.py

@@ -66,8 +66,8 @@
 MAX_WRITE_BATCH_SIZE = 1000
 
 # What this version of PyMongo supports.
-MIN_SUPPORTED_SERVER_VERSION = "3.6"
-MIN_SUPPORTED_WIRE_VERSION = 6
+MIN_SUPPORTED_SERVER_VERSION = "4.0"
+MIN_SUPPORTED_WIRE_VERSION = 7
 # MongoDB 8.0
 MAX_SUPPORTED_WIRE_VERSION = 25
 

pymongo/synchronous/collection.py

@@ -1959,20 +1959,15 @@ def _count_cmd(
         collation: Optional[Collation],
     ) -> int:
         """Internal count command helper."""
-        # XXX: "ns missing" checks can be removed when we drop support for
-        # MongoDB 3.0, see SERVER-17051.
         res = self._command(
             conn,
             cmd,
             read_preference=read_preference,
-            allowable_errors=["ns missing"],
             codec_options=self._write_response_codec_options,
             read_concern=self.read_concern,
             collation=collation,
             session=session,
         )
-        if res.get("errmsg", "") == "ns missing":
-            return 0
         return int(res["n"])
 
     def _aggregate_one_result(

pymongo/synchronous/mongo_client.py

@@ -496,9 +496,8 @@ def __init__(
           - `authSource`: The database to authenticate on. Defaults to the
             database specified in the URI, if provided, or to "admin".
           - `authMechanism`: See :data:`~pymongo.auth.MECHANISMS` for options.
-            If no mechanism is specified, PyMongo automatically SCRAM-SHA-1
-            when connected to MongoDB 3.6 and negotiates the mechanism to use
-            (SCRAM-SHA-1 or SCRAM-SHA-256) when connected to MongoDB 4.0+.
+            If no mechanism is specified, PyMongo automatically negotiates the
+            mechanism to use (SCRAM-SHA-1 or SCRAM-SHA-256) with the MongoDB server.
           - `authMechanismProperties`: Used to specify authentication mechanism
             specific options. To specify the service name for GSSAPI
             authentication pass authMechanismProperties='SERVICE_NAME:<service