Drop support for Python 3.6 (#10945)

* remove Python 3.6 from CI workflows

* update env files

* udpate build configs

* update classifiers

* update docs references

* start release notes

* mypy tweaks for 3.7

* update bokeh info docstring

.github/workflows/bokeh-ci.yml

@@ -103,7 +103,7 @@ jobs:
         with:
           miniconda-version: 'latest'
           activate-environment: bk-test
-          environment-file: ci/environment-test-3.6.yml
+          environment-file: ci/environment-test-3.7.yml
 
       - name: Download Bokehjs
         uses: actions/download-artifact@v1
@@ -269,7 +269,7 @@ jobs:
       max-parallel: 6
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: [3.7, 3.8, 3.9]
 
     steps:
       - uses: actions/checkout@v2
@@ -333,7 +333,7 @@ jobs:
         with:
           miniconda-version: 'latest'
           activate-environment: bk-test
-          environment-file: ci/environment-test-3.6.yml
+          environment-file: ci/environment-test-3.7.yml
 
       - name: Download Bokehjs
         uses: actions/download-artifact@v1
@@ -435,7 +435,7 @@ jobs:
         with:
           miniconda-version: 'latest'
           activate-environment: bk-test
-          environment-file: ci/environment-test-3.6.yml
+          environment-file: ci/environment-test-3.7.yml
 
       - name: Install downstream packages
         shell: bash -l {0}

bokeh/command/subcommands/info.py

@@ -17,12 +17,13 @@
 
 .. code-block:: none
 
-    Python version      :  3.6.5
-    IPython version     :  6.3.1
-    Bokeh version       :  0.12.15
-    BokehJS static path :  /opt/anaconda/lib/python3.6/site-packages/bokeh/server/static
-    node.js version     :  v8.11.1
-    npm version         :  5.8.0
+    Python version      :  3.9.1 (default, Dec 11 2020, 06:28:49)
+    IPython version     :  7.20.0
+    Tornado version     :  6.1
+    Bokeh version       :  2.3.0
+    BokehJS static path :  /opt/anaconda/envs/test/lib/python3.9/site-packages/bokeh/server/static
+    node.js version     :  v15.10.0
+    npm version         :  7.5.3
 
 Sometimes it can be useful to get just paths to the BokehJS static files in order
 to configure other servers or processes. To do this, use the ``--static`` option
@@ -35,7 +36,7 @@
 
 .. code-block:: none
 
-    /opt/anaconda/lib/python3.6/site-packages/bokeh/server/static
+    /opt/anaconda/envs/test/lib/python3.9/site-packages/bokeh/server/static
 
 '''
 

bokeh/server/tornado.py

@@ -167,11 +167,11 @@ class BokehTornado(TornadoApplication):
 
         websocket_compression_level (int, optional):
             Set the Tornado WebSocket ``compression_level`` documented in
-            https://docs.python.org/3.6/library/zlib.html#zlib.compressobj.
+            https://docs.python.org/3.7/library/zlib.html#zlib.compressobj.
 
         websocket_compression_mem_level (int, optional):
             Set the Tornado WebSocket compression ``mem_level`` documented in
-            https://docs.python.org/3.6/library/zlib.html#zlib.compressobj.
+            https://docs.python.org/3.7/library/zlib.html#zlib.compressobj.
 
         index (str, optional):
             Path to a Jinja2 template to use for the root URL

ci/environment-build.yml

@@ -2,7 +2,7 @@ name: bk-test
 channels:
   - conda-forge
 dependencies:
-  - python=3.6
+  - python=3.7
   - conda-build=3.18.10
   - conda-verify=3.4.2
   - libiconv

classifiers.txt

@@ -18,6 +18,7 @@ Topic :: Scientific/Engineering :: Information Analysis
 Topic :: Utilities
 Programming Language :: Python
 Programming Language :: Python :: 3
-Programming Language :: Python :: 3.6
 Programming Language :: Python :: 3.7
+Programming Language :: Python :: 3.8
+Programming Language :: Python :: 3.9
 Programming Language :: JavaScript

conda.recipe/meta.yaml

@@ -32,10 +32,10 @@ requirements:
     - yaml
 
   host:
-    - python >=3.6
+    - python >=3.7
 
   run:
-    - python >=3.6
+    - python >=3.7
 
     {% for dep in data['install_requires'] %}
     - {{ dep.lower() }}

docker-tools/README.md

@@ -39,7 +39,7 @@ Note that some examples require additional Python modules and hence will result
 Choose a bokeh version to install from the available versions on anaconda.
 Run `conda search bokeh` for the available versions. Then, build the image using, for example, version 1.4.0:
 ``` shell
-docker build -t bokeh:dev-py3 --build-arg PYTHON=3.6 -f docker-tools/Dockerfile-from-travis .
+docker build -t bokeh:dev-py3 --build-arg PYTHON=3.7 -f docker-tools/Dockerfile-from-travis .
 ```
 
 Also here, you can test the image by `docker run -it`

environment.yml

@@ -2,7 +2,7 @@ name: bkdev
 channels:
   - conda-forge
 dependencies:
-  - python>=3.6
+  - python>=3.7
 
   # build
   - setuptools

release/system.py

@@ -12,7 +12,7 @@
 import os
 from subprocess import PIPE, STDOUT
 from subprocess import run as stdlib_run
-from typing import Any, List, cast
+from typing import Any, List
 
 # Bokeh imports
 from .logger import LOG
@@ -39,12 +39,12 @@ def run(self, cmd: str, **kw: Any) -> str:
         if self.dry_run:
             return ""
 
-        result = stdlib_run(cmd, shell=True, stdout=PIPE, stderr=STDOUT, text=True, env=env)  # type: ignore
+        result = stdlib_run(cmd, shell=True, stdout=PIPE, stderr=STDOUT, text=True, env=env)
 
         if result.returncode != 0:
             raise RuntimeError(*result.stdout.strip().split("\n"))
 
-        return cast(str, result.stdout)
+        return result.stdout
 
     def abort(self) -> None:
         """"""

setup.cfg

@@ -43,7 +43,7 @@ parentdir_prefix = Bokeh-
 style = git-describe
 
 [mypy]
-python_version = 3.6
+python_version = 3.7
 
 pretty = True
 show_error_codes = True

setup.py

@@ -71,8 +71,8 @@
 )
 
 # immediately bail on unsupported Python versions
-if sys.version_info[:2] < (3, 6):
-    raise RuntimeError("Bokeh requires python >= 3.6")
+if sys.version_info[:2] < (3, 7):
+    raise RuntimeError("Bokeh requires python >= 3.7")
 
 # we want to have the license at the top level of the GitHub repo, but setup
 # can't include it from there, so copy it to the package directory first thing
@@ -117,7 +117,7 @@
 
     # details needed by setup
     install_requires=REQUIRES,
-    python_requires=">=3.6",
+    python_requires=">=3.7",
     packages=find_packages(include=["bokeh", "bokeh.*"]),
     include_package_data=True,
     entry_points={'console_scripts': ['bokeh = bokeh.__main__:main']},

sphinx/source/docs/first_steps.rst

@@ -16,7 +16,7 @@ First steps
 Installing Bokeh
 ----------------
 
-Bokeh is officially supported and tested on Python 3.6 and above (CPython).
+Bokeh is officially supported and tested on Python 3.7 and above (CPython).
 
 You can install Bokeh with either ``conda`` or ``pip``:
 

sphinx/source/docs/first_steps/installation.rst

@@ -11,7 +11,7 @@ Supported platforms
 -------------------
 
 Bokeh is officially supported (and continuously tested) on CPython versions
-3.6+ only. It's possible that Bokeh does work on other versions of Python, but
+3.7+ only. It's possible that Bokeh does work on other versions of Python, but
 no guarantees or support are provided.
 
 Installing with ``conda`` or ``pip``

sphinx/source/docs/releases/2.4.0.rst

@@ -0,0 +1,23 @@
+.. _release-2-4-0:
+
+2.4.0
+=====
+
+Bokeh Version ``2.4.0`` (XXXXXX 2021) is a new minor-release level that
+brings many updates. Some of the new feature work includes:
+
+
+And several other bug fixes and docs additions. For full details see the
+:bokeh-tree:`CHANGELOG`.
+
+.. _release-2-4-0-migration:
+
+`Migration Guide <releases.html#release-2-4-0-migration>`__
+-----------------------------------------------------------
+
+Minimum Package Versions
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+This release raises the minimum version for some packages
+
+* Bokeh now requires Python 3.7 or higher.