Drop Python 3.8 from workflows, run on 3.11 (#3228)

*Issue #, if available:* Python 3.8 reached EOL, and some packages are
not distributed for it in their latest versions.

*Description of changes:*
- update github workflows to run on Python (up to) 3.11
- fix tests and testutils that would break on 3.11
- delete some unused workflows
- update sphinx version used in the docs build workflow


By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice.


**Please tag this pr with at least one of these labels to make our
release process faster:** BREAKING, new feature, bug fix, other change,
dev setup

.github/workflows/docs.yml

@@ -20,10 +20,9 @@ jobs:
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
-    - name: Set up Python 3.8
-      uses: actions/setup-python@v4
+    - uses: actions/setup-python@v4
       with:
-        python-version: 3.8
+        python-version: 3.11
 
     - name: Install dependencies
       run: |

.github/workflows/doctests.yaml

@@ -8,15 +8,14 @@ jobs:
       max-parallel: 4
       fail-fast: false
       matrix:
-        python-version: ['3.9']
+        python-version: ['3.11']
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}
 
     steps:
     - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
+    - uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install other dependencies

.github/workflows/lints.yml

@@ -12,6 +12,8 @@ jobs:
     steps:
     - uses: actions/checkout@v3
     - uses: actions/setup-python@v4
+      with:
+          python-version: '3.11'
     - name: Install tools
       run: pip install "ruff==0.2.2" "docformatter[tomli]==1.5.0"
     - name: Ruff (Flake8)

.github/workflows/pypi.yml

@@ -12,10 +12,9 @@ jobs:
     - uses: actions/checkout@v4
     - name: Get tags
       run: git fetch --tags origin
-    - name: Set up Python 3.8
-      uses: actions/setup-python@v4
+    - uses: actions/setup-python@v4
       with:
-        python-version: '3.8'
+        python-version: '3.11'
     - name: Install dependencies
       run: |
         python -m pip install -U pip

.github/workflows/style_type_checks.yml

@@ -10,6 +10,8 @@ jobs:
     - uses: actions/checkout@v3
     - uses: extractions/setup-just@v1
     - uses: actions/setup-python@v4
+      with:
+          python-version: '3.11'
     - name: Install dependencies
       run: |
         pip install .

.github/workflows/tests-nixtla.yaml

@@ -8,15 +8,14 @@ jobs:
       max-parallel: 4
       fail-fast: false
       matrix:
-        python-version: ['3.8']
+        python-version: ['3.11']
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}
 
     steps:
     - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
+    - uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install other dependencies

.github/workflows/tests-nursery.yml

@@ -8,7 +8,7 @@ jobs:
       max-parallel: 1
       fail-fast: false
       matrix:
-        python-version: ['3.8']
+        python-version: ['3.11']
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}
@@ -17,8 +17,7 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
+    - uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install MXNet (Linux)

.github/workflows/tests-prophet.yaml

@@ -8,15 +8,14 @@ jobs:
       max-parallel: 4
       fail-fast: false
       matrix:
-        python-version: ['3.8']
+        python-version: ['3.11']
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}
 
     steps:
     - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
+    - uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install other dependencies

.github/workflows/tests-r.yml

@@ -8,7 +8,7 @@ jobs:
       max-parallel: 4
       fail-fast: false
       matrix:
-        python-version: ['3.9']
+        python-version: ['3.11']
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}
@@ -32,8 +32,7 @@ jobs:
           libxml2-dev \
           libcurl4-openssl-dev
         Rscript -e 'install.packages(c("forecast", "nnfor", "hts"), repos="https://cloud.r-project.org")'
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
+    - uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install Python dependencies

.github/workflows/tests-torch.yml

@@ -8,7 +8,7 @@ jobs:
       max-parallel: 4
       fail-fast: false
       matrix:
-        python-version: ['3.8', '3.9', '3.10']
+        python-version: ['3.9', '3.10', '3.11']
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}

.github/workflows/tests-xgboost.yaml

@@ -8,7 +8,7 @@ jobs:
       max-parallel: 4
       fail-fast: false
       matrix:
-        python-version: ['3.8', '3.9', '3.10']
+        python-version: ['3.11']
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}

.github/workflows/tests.yml

@@ -8,15 +8,14 @@ jobs:
       max-parallel: 4
       fail-fast: false
       matrix:
-        python-version: ['3.8', '3.9', '3.10']
+        python-version: ['3.9', '3.10', '3.11']
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}
 
     steps:
     - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
+    - uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install other dependencies

requirements/requirements-docs.txt

@@ -6,7 +6,7 @@ notedown
 lxml~=5.1.0
 pytest-runner~=2.11
 recommonmark
-sphinx~=4.0
+sphinx~=5.0
 docutils<=0.16
 optuna~=2.10
 furo==2022.6.4.1

src/gluonts/testutil/shell.py

@@ -21,7 +21,7 @@
 import typing
 import waitress
 from contextlib import closing, contextmanager
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from multiprocessing.context import ForkContext
 from pathlib import Path
 from typing import Any, ContextManager, Dict, Iterable, List, Optional, Type
@@ -119,7 +119,7 @@ def free_port() -> int:
 class Server:
     env: ServeEnv
     forecaster_type: Optional[Type[Predictor]]
-    settings: Settings = Settings()
+    settings: Settings = field(default_factory=Settings)
 
     def run(self):
         flask_app = make_flask_app(

test/conftest.py

@@ -30,7 +30,7 @@
 
 try:
     import mxnet as mx
-except ImportError:
+except (ImportError, OSError):
     mx = None
 
 try:

test/core/test_serde_dataclass.py

@@ -20,14 +20,13 @@
 @serde.dataclass
 class Estimator:
     prediction_length: int
-    context_length: int = serde.OrElse(
-        lambda prediction_length: prediction_length * 2
-    )
+    context_length: int = serde.EVENTUAL
 
     use_feat_static_cat: bool = True
     cardinality: List[int] = serde.EVENTUAL
 
-    def __eventually__(self, cardinality):
+    def __eventually__(self, context_length, cardinality):
+        context_length.set_default(self.prediction_length * 2)
         if not self.use_feat_static_cat:
             cardinality.set([1])
         else: