[Triage] Cleanup: reduce runtime dependency on 'packaging' to {gevent, eventlet, tests} contexts

[jayaddison]

Type

Feature Request

Description

Reviewing some dependencies, I found packaging as a transitive dependency of gunicorn; this is configured in the pyproject.toml file:

gunicorn/pyproject.toml

Lines 37 to 39 in 4bcda32

	dependencies = [
	"packaging",
	]

Unless the eventlet or gevent extras are specified when installing gunicorn (e.g. pip install gunicorn[eventlet]), the packaging package does not appear to be a required runtime dependency.

It is used by each of the two worker types mentioned:

• eventlet:

  gunicorn/gunicorn/workers/geventlet.py

  Lines 20 to 29 in 4bcda32

  	# NOTE: eventlet import and monkey_patch() must happen before any other imports
  	# to ensure all standard library modules are properly patched.
  	try:
  	import eventlet
  	except ImportError:
  	raise RuntimeError("eventlet worker requires eventlet 0.40.3 or higher")
  	else:
  	from packaging.version import parse as parse_version
  	if parse_version(eventlet.__version__) < parse_version('0.40.3'):
  	raise RuntimeError("eventlet worker requires eventlet 0.40.3 or higher")

• gevent:

  gunicorn/gunicorn/workers/ggevent.py

  Lines 11 to 18 in 4bcda32

  	try:
  	import gevent
  	except ImportError:
  	raise RuntimeError("gevent worker requires gevent 24.10.1 or higher")
  	else:
  	from packaging.version import parse as parse_version
  	if parse_version(gevent.__version__) < parse_version('24.10.1'):
  	raise RuntimeError("gevent worker requires gevent 24.10.1 or higher")

...and it is required by the gunicorn test suite:

• test_gevent:

  gunicorn/tests/workers/test_ggevent.py

  Lines 22 to 26 in 4bcda32

  	def test_version_requirement():
  	"""Test that gevent 24.10.1+ is required."""
  	from gunicorn.workers import ggevent
  	from packaging.version import parse as parse_version
  	assert parse_version(gevent.__version__) >= parse_version('24.10.1')

Steps to Reproduce (for bugs)

Either:

Inspect the METADATA file of a recent installed copy of gunicorn (e.g. v25.3.0):

...
Classifier: Topic :: Internet :: WWW/HTTP
Classifier: Topic :: Internet :: WWW/HTTP :: WSGI
Classifier: Topic :: Internet :: WWW/HTTP :: WSGI :: Server
Classifier: Topic :: Internet :: WWW/HTTP :: Dynamic Content
Requires-Python: >=3.10
Description-Content-Type: text/markdown
License-File: LICENSE
Requires-Dist: packaging
Provides-Extra: gevent
Requires-Dist: gevent>=24.10.1; extra == "gevent"
Provides-Extra: eventlet
Requires-Dist: eventlet>=0.40.3; extra == "eventlet"
...

Or:

Locate imports of the packaging package in a checkout of the gunicorn git repository:

$ git clone https://github.com/benoitc/gunicorn/
$ cd gunicorn
$ git checkout 25.3.0
$ find . -type f -name '*.py' -exec grep -w packaging {} +

Configuration

N/A

Logs / Error Output

N/A

Gunicorn Version

gunicorn 25.3.0

Python Version

N/A

Worker Class

N/A (feature request)

Operating System

N/A

Additional Context

Proposed solution:

1. Add packaging to the requirements_test.txt file to ensure that the dependency is installed for testing.
2. Add packaging to the relevant worker extras in pyproject.toml.
3. Remove packaging from the base runtime requirements for gunicorn (also in pyproject.toml).

For example:

diff --git a/pyproject.toml b/pyproject.toml
index f6c26b4f..298b4603 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,9 +34,6 @@ classifiers = [
     "Topic :: Internet :: WWW/HTTP :: Dynamic Content",
 ]
 requires-python = ">=3.10"
-dependencies = [
-    "packaging",
-]
 dynamic = ["version"]
 
 [project.urls]
@@ -47,8 +44,14 @@ Documentation = "https://gunicorn.org"
 Changelog = "https://gunicorn.org/news/"
 
 [project.optional-dependencies]
-gevent = ["gevent>=24.10.1"]
-eventlet = ["eventlet>=0.40.3"]
+gevent = [
+    "gevent>=24.10.1",
+    "packaging",
+]
+eventlet = [
+    "eventlet>=0.40.3",
+    "packaging",
+]
 tornado = ["tornado>=6.5.0"]
 gthread = []
 setproctitle = ["setproctitle"]
diff --git a/requirements_test.txt b/requirements_test.txt
index b1abc181..7ccc0a3e 100644
--- a/requirements_test.txt
+++ b/requirements_test.txt
@@ -1,5 +1,6 @@
 gevent
 coverage
+packaging
 pytest>=7.2.0
 pytest-cov
 pytest-asyncio

Checklist

• I have searched existing discussions and issues for duplicates
• I have checked the documentation and FAQ

[jayaddison]

NB: with the eventlet engine removed in v26.0.0 I think that gevent is the only remaining dependee of packaging in gunicorn.