Add Python 3.14 support by forcing parallelism to use fork (#434)

* Add Python 3.14 support

* Address review comments

* Force fork start method for multiprocessing (Python 3.14+)

Co-authored-by: forsyth2 <30700190+forsyth2@users.noreply.github.com>

* Fix tar.extract filter for Python 3.12+ to allow absolute symlinks

Co-authored-by: forsyth2 <30700190+forsyth2@users.noreply.github.com>

* Fix pre-commit checks

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

Author: forsyth2

.github/workflows/build_workflow.yml

@@ -19,10 +19,10 @@ jobs:
       - name: Checkout Code Repository
         uses: actions/checkout@v3
 
-      - name: Set up Python 3.13
+      - name: Set up Python 3.14
         uses: actions/setup-python@v4
         with:
-          python-version: "3.13"
+          python-version: "3.14"
 
       # Run all pre-commit hooks on all the files.
       # Getting only staged files can be tricky in case a new PR is opened
@@ -36,7 +36,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.11", "3.12", "3.13"]
+        python-version: ["3.11", "3.12", "3.13", "3.14"]
     defaults:
       run:
         shell: bash -l {0}
@@ -72,11 +72,6 @@ jobs:
           conda list
           # Ensure we have the right Python version
           python --version
-          # Fix pip issues for Python 3.12+
-          if [[ "${{ matrix.python-version }}" == "3.12" ]] || [[ "${{ matrix.python-version }}" == "3.13" ]]; then
-            python -m ensurepip --upgrade || true
-            python -m pip install --upgrade --force-reinstall pip setuptools wheel
-          fi
 
       - name: Install `zstash` Package
         run: |
@@ -121,7 +116,7 @@ jobs:
           environment-file: conda/dev.yml
           channel-priority: flexible  # Changed from strict to flexible
           auto-update-conda: true
-          python-version: "3.13"  # Use stable Python version for docs
+          python-version: "3.14"  # Use stable Python version for docs
 
       # sphinx-multiversion allows for version docs.
       - name: Build Sphinx Docs

conda/dev.yml

@@ -5,7 +5,8 @@ dependencies:
   # Base
   # =================
   - pip
-  - python >=3.11,<3.14
+  - python >=3.11,<3.15
+  - setuptools
   - sqlite
   - six >=1.16.0
   - globus-sdk >=3.15.0,<4.0

setup.cfg

@@ -46,7 +46,7 @@ exclude =
     venv
 
 [mypy]
-python_version = 3.13
+python_version = 3.14
 check_untyped_defs = True
 ignore_missing_imports = True
 warn_unused_ignores = True

setup.py

@@ -7,6 +7,6 @@
     author_email="forsyth2@llnl.gov, golaz1@llnl.gov, shaheen2@llnl.gov",
     description="Long term HPSS archiving software for E3SM",
     packages=find_packages(include=["zstash", "zstash.*"]),
-    python_requires=">=3.11,<3.14",
+    python_requires=">=3.11,<3.15",
     entry_points={"console_scripts": ["zstash=zstash.main:main"]},
 )

zstash/extract.py

@@ -659,7 +659,12 @@ def extractFiles(  # noqa: C901
                     logger.debug("Valid md5: {} {}".format(md5, fname))
 
             elif extract_this_file:
-                tar.extract(tarinfo)
+                if sys.version_info >= (3, 12):
+                    tar.extract(
+                        tarinfo, filter="tar"
+                    )  # "data" is too restrictive, "fully_trusted" is too permissive.
+                else:
+                    tar.extract(tarinfo)
                 # Note: tar.extract() will not restore time stamps of symbolic
                 # links. Could not find a Python-way to restore it either, so
                 # relying here on 'touch'. This is not the prettiest solution.

zstash/main.py

@@ -2,6 +2,7 @@
 from __future__ import absolute_import, print_function
 
 import argparse
+import multiprocessing
 import os
 import os.path
 import sys
@@ -27,6 +28,12 @@ def handler(signal_received, frame):
 # -----------------------------------------------------------------------------
 def main():
 
+    # Force the use of 'fork' for multiprocessing to ensure consistent behavior
+    # across Python versions (Python 3.14+ changed the default to 'spawn').
+    # 'fork' is only available on POSIX systems (Linux, macOS).
+    if sys.platform != "win32":
+        multiprocessing.set_start_method("fork", force=True)
+
     # Run the handler() function when SIGINT is received
     signal(SIGINT, handler)