PYTHON-2833 MongoDB 3.6 is the minimum supported version

This change drops support for server versions older than 3.6. If you still need support for older server versions the 3.x branch of PyMongo will receive bug fixes for at least a year after the release of PyMongo 4.0.

Author: behackett

.evergreen/config.yml

@@ -968,114 +968,6 @@ tasks:
  TOPOLOGY: "server"
  - func: "run doctests"
 
- - name: "test-2.6-standalone"
- tags: ["2.6", "standalone"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "2.6"
- TOPOLOGY: "server"
- - func: "run tests"
-
- - name: "test-2.6-replica_set"
- tags: ["2.6", "replica_set"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "2.6"
- TOPOLOGY: "replica_set"
- - func: "run tests"
-
- - name: "test-2.6-sharded_cluster"
- tags: ["2.6", "sharded_cluster"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "2.6"
- TOPOLOGY: "sharded_cluster"
- - func: "run tests"
-
- - name: "test-3.0-standalone"
- tags: ["3.0", "standalone"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.0"
- TOPOLOGY: "server"
- - func: "run tests"
-
- - name: "test-3.0-replica_set"
- tags: ["3.0", "replica_set"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.0"
- TOPOLOGY: "replica_set"
- - func: "run tests"
-
- - name: "test-3.0-sharded_cluster"
- tags: ["3.0", "sharded_cluster"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.0"
- TOPOLOGY: "sharded_cluster"
- - func: "run tests"
-
- - name: "test-3.2-standalone"
- tags: ["3.2", "standalone"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.2"
- TOPOLOGY: "server"
- - func: "run tests"
-
- - name: "test-3.2-replica_set"
- tags: ["3.2", "replica_set"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.2"
- TOPOLOGY: "replica_set"
- - func: "run tests"
-
- - name: "test-3.2-sharded_cluster"
- tags: ["3.2", "sharded_cluster"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.2"
- TOPOLOGY: "sharded_cluster"
- - func: "run tests"
-
- - name: "test-3.4-standalone"
- tags: ["3.4", "standalone"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.4"
- TOPOLOGY: "server"
- - func: "run tests"
-
- - name: "test-3.4-replica_set"
- tags: ["3.4", "replica_set"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.4"
- TOPOLOGY: "replica_set"
- - func: "run tests"
-
- - name: "test-3.4-sharded_cluster"
- tags: ["3.4", "sharded_cluster"]
- commands:
- - func: "bootstrap mongo-orchestration"
- vars:
- VERSION: "3.4"
- TOPOLOGY: "sharded_cluster"
- - func: "run tests"
-
  - name: "test-3.6-standalone"
  tags: ["3.6", "standalone"]
  commands:
@@ -1843,22 +1735,6 @@ axes:
  - id: mongodb-version
  display_name: "MongoDB"
  values:
- - id: "2.6"
- display_name: "MongoDB 2.6"
- variables:
- VERSION: "2.6"
- - id: "3.0"
- display_name: "MongoDB 3.0"
- variables:
- VERSION: "3.0"
- - id: "3.2"
- display_name: "MongoDB 3.2"
- variables:
- VERSION: "3.2"
- - id: "3.4"
- display_name: "MongoDB 3.4"
- variables:
- VERSION: "3.4"
  - id: "3.6"
  display_name: "MongoDB 3.6"
  variables:
@@ -2018,10 +1894,6 @@ axes:
  display_name: MMAPv1
  variables:
  STORAGE_ENGINE: "mmapv1"
- - id: wiredtiger
- display_name: WiredTiger
- variables:
- STORAGE_ENGINE: "wiredtiger"
  - id: inmemory
  display_name: InMemory
  variables:
@@ -2123,10 +1995,6 @@ buildvariants:
  - ".4.2"
  - ".4.0"
  - ".3.6"
- - ".3.4"
- - ".3.2"
- - ".3.0"
- - ".2.6"
 
 - matrix_name: "tests-all-encryption"
  matrix_spec:
@@ -2142,7 +2010,6 @@ buildvariants:
  - ".4.4"
  - ".4.2"
  - ".4.0"
- - ".2.6"
 
 - matrix_name: "tests-archlinux"
  matrix_spec:
@@ -2156,10 +2023,6 @@ buildvariants:
  tasks:
  - ".4.0"
  - ".3.6"
- - ".3.4"
- - ".3.2"
- - ".3.0"
- - ".2.6"
 
 - matrix_name: "test-macos"
  matrix_spec:
@@ -2182,17 +2045,6 @@ buildvariants:
  - ".4.2"
  - ".4.0"
  - ".3.6"
- - ".3.4"
- - ".3.2"
- rules:
- - if:
- platform: macos-1014
- auth: "*"
- ssl: "nossl"
- then:
- add_tasks:
- - ".3.0"
- - ".2.6"
 
 - matrix_name: "test-macos-encryption"
  matrix_spec:
@@ -2252,7 +2104,7 @@ buildvariants:
  pyopenssl: "*"
  display_name: "PyOpenSSL ${platform} ${python-version} ${auth}"
  tasks:
- - '.replica_set !.2.6 !.3.0'
+ - '.replica_set'
  # Test standalone and sharded only on 5.0 and later.
  - '.5.0'
 
@@ -2265,7 +2117,7 @@ buildvariants:
  pyopenssl: "*"
  display_name: "PyOpenSSL ${platform} ${python-version} ${auth}"
  tasks:
- - '.replica_set !.2.6 !.3.0 !.3.2 !.3.4'
+ - '.replica_set'
  # Test standalone and sharded only on 5.0 and later.
  - '.5.0'
 
@@ -2277,7 +2129,7 @@ buildvariants:
  pyopenssl: "*"
  display_name: "PyOpenSSL ${platform} ${auth}"
  tasks:
- - '.replica_set !.2.6 !.3.0'
+ - '.replica_set'
 
 - matrix_name: "tests-pyopenssl-windows"
  matrix_spec:
@@ -2432,8 +2284,6 @@ buildvariants:
  - "test-4.2-standalone"
  - "test-4.0-standalone"
  - "test-3.6-standalone"
- - "test-3.4-standalone"
- - "test-3.2-standalone"
  - if:
  # MongoDB 4.2 drops support for MMAPv1
  platform: awslinux
@@ -2445,16 +2295,6 @@ buildvariants:
  - "test-4.0-replica_set"
  - "test-3.6-standalone"
  - "test-3.6-replica_set"
- - "test-3.4-standalone"
- - "test-3.2-standalone"
- - if:
- # No need to test this on later server versions as it becomes the default
- platform: awslinux
- storage-engine: ["wiredtiger"]
- python-version: "*"
- then:
- add_tasks:
- - "test-3.0-standalone"
 
 # enableTestCommands=0 tests on Amazon1 (x86_64) with Python 3.6.
 - matrix_name: "test-disableTestCommands"

README.rst

@@ -17,7 +17,7 @@ is a `gridfs
 <http://www.mongodb.org/display/DOCS/GridFS+Specification>`_
 implementation on top of ``pymongo``.
 
-PyMongo supports MongoDB 2.6, 3.0, 3.2, 3.4, 3.6, 4.0, 4.2, 4.4, and 5.0.
+PyMongo supports MongoDB 3.6, 4.0, 4.2, 4.4, and 5.0.
 
 Support / Feedback
 ==================

doc/changelog.rst

@@ -6,6 +6,8 @@ Changes in Version 4.0
 
 .. warning:: PyMongo 4.0 drops support for Python 2.7, 3.4, and 3.5.
 
+.. warning:: PyMongo 4.0 drops support for MongoDB 2.6, 3.0, 3.2, and 3.4.
+
 PyMongo 4.0 brings a number of improvements as well as some backward breaking
 changes. For example, all APIs deprecated in PyMongo 3.X have been removed.
 Be sure to read the changes listed below and the :doc:`migrate-to-pymongo4`

pymongo/common.py

@@ -47,8 +47,8 @@
 MAX_WRITE_BATCH_SIZE = 1000
 
 # What this version of PyMongo supports.
-MIN_SUPPORTED_SERVER_VERSION = "2.6"
-MIN_SUPPORTED_WIRE_VERSION = 2
+MIN_SUPPORTED_SERVER_VERSION = "3.6"
+MIN_SUPPORTED_WIRE_VERSION = 6
 MAX_SUPPORTED_WIRE_VERSION = 13
 
 # Frequency to call ismaster on servers, in seconds.