Migrate from pkg_resources to importlib (#3232)

src/pretix/base/plugins.py

@@ -24,9 +24,11 @@ import sys
 from enum import Enum
 from typing import List
 
+import importlib_metadata as metadata
 from django.apps import AppConfig, apps
 from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured
+from packaging.requirements import Requirement
 
 
 class PluginType(Enum):
@@ -81,12 +83,11 @@ class PluginConfig(AppConfig, metaclass=PluginConfigMeta):
             raise ImproperlyConfigured("A pretix plugin config should have a PretixPluginMeta inner class.")
 
         if hasattr(self.PretixPluginMeta, 'compatibility') and not os.environ.get("PRETIX_IGNORE_CONFLICTS") == "True":
-            import pkg_resources
+            req = Requirement(self.PretixPluginMeta.compatibility)
-            try:
+            requirement_version = metadata.version(req.name)
-                pkg_resources.require(self.PretixPluginMeta.compatibility)
+            if not req.specifier.contains(requirement_version, prereleases=True):
-            except pkg_resources.VersionConflict as e:
                 print("Incompatible plugins found!")
                 print("Plugin {} requires you to have {}, but you installed {}.".format(
-                    self.name, e.req, e.dist
+                    self.name, req, requirement_version
                 ))
                 sys.exit(1)

src/pretix/control/views/global_settings.py

@@ -31,8 +31,7 @@
 # Unless required by applicable law or agreed to in writing, software distributed under the Apache License 2.0 is
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under the License.
-
+import importlib_metadata as metadata
-import pkg_resources
 from django.contrib import messages
 from django.http import JsonResponse
 from django.shortcuts import get_object_or_404, redirect, reverse
@@ -132,14 +131,14 @@ class LicenseCheckView(StaffMemberRequiredMixin, FormView):
         if not d:
             d['source_notice'] = 'pretix (AGPLv3 with additional terms): https://github.com/pretix/pretix'
             seen = set()
-            for entry_point in pkg_resources.iter_entry_points(group='pretix.plugin', name=None):
+            for entry_point in metadata.entry_points(group='pretix.plugin'):
-                if entry_point.dist.key not in seen:
+                if entry_point.dist.name not in seen:
                     try:
-                        license, url = self._get_license_for_pkg(entry_point.dist.key)
+                        license, url = self._get_license_for_pkg(entry_point.dist.name)
                     except FileNotFoundError:
                         license, url = '?', '?'
-                    d['source_notice'] += f'\n{entry_point.dist.key} ({license}): {url}'
+                    d['source_notice'] += f'\n{entry_point.dist.name} ({license}): {url}'
-                    seen.add(entry_point.dist.key)
+                    seen.add(entry_point.dist.name)
 
         return d
 
@@ -168,17 +167,15 @@ class LicenseCheckView(StaffMemberRequiredMixin, FormView):
     def _get_license_for_pkg(self, pkg):
         license, url = None, None
         try:
-            pkg = pkg_resources.get_distribution(pkg)
+            pkg = metadata.distribution(pkg)
         except:
             return None, None
         try:
-            for line in pkg.get_metadata_lines(pkg.PKG_INFO):
+            for k, v in pkg.metadata.items():
-                if ': ' in line:
+                if k == "License":
-                    (k, v) = line.split(': ', 1)
+                    license = v
-                    if k == "License":
+                if k == "Home-page":
-                        license = v
+                    url = v
-                    if k == "Home-page":
-                        url = v
         except FileNotFoundError:
             license = '?'
             url = '?'
@@ -232,14 +229,14 @@ class LicenseCheckView(StaffMemberRequiredMixin, FormView):
                       'restrictions). Make sure to keep it up to date!')
                 ))
 
-        for entry_point in pkg_resources.iter_entry_points(group='pretix.plugin', name=None):
+        for entry_point in metadata.entry_points(group='pretix.plugin'):
-            license, url = self._get_license_for_pkg(entry_point.dist.key)
+            license, url = self._get_license_for_pkg(entry_point.dist.name)
 
             if not license or not any(l in license for l in ('Apache', 'MIT', 'BSD', 'pretix Enterprise', 'GPL')):
                 res.append((
                     'muted', 'warning',
                     _('We found the plugin "{plugin}" with license "{license}" which this tool does not know about and '
-                      'therefore cannot give any recommendations.').format(plugin=entry_point.dist.key, license=license)
+                      'therefore cannot give any recommendations.').format(plugin=entry_point.dist.name, license=license)
                 ))
                 continue
 
@@ -247,21 +244,21 @@ class LicenseCheckView(StaffMemberRequiredMixin, FormView):
                 res.append((
                     'danger', 'exclamation-circle',
                     _('You selected that you have no active pretix Enterprise licenses, but we found the following '
-                      'Enterprise plugin: {plugin}').format(plugin=entry_point.dist.key)
+                      'Enterprise plugin: {plugin}').format(plugin=entry_point.dist.name)
                 ))
 
             if not input.get('plugins_copyleft') and any(l in license for l in ('GPL',)):
                 res.append((
                     'danger', 'exclamation-circle',
                     _('You selected that you have no copyleft-licensed plugins installed, but we found the '
-                      'plugin "{plugin}" with license "{license}".').format(plugin=entry_point.dist.key, license=license)
+                      'plugin "{plugin}" with license "{license}".').format(plugin=entry_point.dist.name, license=license)
                 ))
 
             if not input.get('plugins_free') and any(l in license for l in ('Apache', 'MIT', 'BSD')):
                 res.append((
                     'danger', 'exclamation-circle',
                     _('You selected that you have no free plugins installed, but we found the '
-                      'plugin "{plugin}" with license "{license}".').format(plugin=entry_point.dist.key, license=license)
+                      'plugin "{plugin}" with license "{license}".').format(plugin=entry_point.dist.name, license=license)
                 ))
 
         return res

src/pretix/settings.py

@@ -41,9 +41,9 @@ from urllib.parse import urlparse
 from json import loads
 
 import django.conf.locale
+import importlib_metadata as metadata
 from django.utils.crypto import get_random_string
 from kombu import Queue
-from pkg_resources import iter_entry_points
 from pycountry import currencies
 
 from . import __version__
@@ -401,11 +401,11 @@ except ImportError:
     pass
 
 PLUGINS = []
-for entry_point in iter_entry_points(group='pretix.plugin', name=None):
+for entry_point in metadata.entry_points(group='pretix.plugin'):
-    if entry_point.module_name in PRETIX_PLUGINS_EXCLUDE:
+    if entry_point.module in PRETIX_PLUGINS_EXCLUDE:
         continue
-    PLUGINS.append(entry_point.module_name)
+    PLUGINS.append(entry_point.module)
-    INSTALLED_APPS.append(entry_point.module_name)
+    INSTALLED_APPS.append(entry_point.module)
 
 HIJACK_PERMISSION_CHECK = "hijack.permissions.superusers_and_staff"
 HIJACK_INSERT_BEFORE = None

src/setup.py

@@ -192,6 +192,7 @@ setup(
         'dnspython==2.2.*',
         'drf_ujson2==1.7.*',
         'geoip2==4.*',
+        'importlib-metadata==6.4.*',  # Polyfill, we can probably drop this once we require Python 3.10+
         'isoweek',
         'jsonschema',
         'kombu==5.2.*',