Add a 'limnoria.plugins entrypoint, to discover plugins installed via pip/setuptools.

requirements.txt

@@ -1,3 +1,4 @@
+setuptools
 chardet
 pytz
 python-dateutil

src/plugin.py

@@ -34,23 +34,42 @@ import os.path
 import linecache
 import importlib.util
 
+try:
+    import pkg_resources
+except ImportError:
+    pkg_resources = None
+
 if not hasattr(importlib.util, 'module_from_spec'):
     # Python < 3.5
     import imp
 
 from . import callbacks, conf, log, registry
 
+ENTRYPOINT_GROUPS = [
+    'limnoria.plugins',
+]
+
 installDir = os.path.dirname(sys.modules[__name__].__file__)
 _pluginsDir = os.path.join(installDir, 'plugins')
 
 class Deprecated(ImportError):
     pass
 
+def loadPluginFromEntrypoint(name):
+    if pkg_resources:
+        for entrypoint_group in ENTRYPOINT_GROUPS:
+            for entrypoint in pkg_resources.iter_entry_points(entrypoint_group):
+                if entrypoint.name.lower() == name.lower():
+                    return entrypoint.load()
+
+    return None
+
 def loadPluginModule(name, ignoreDeprecation=False):
     """Loads (and returns) the module for the plugin with the given name."""
     files = []
     pluginDirs = conf.supybot.directories.plugins()[:]
     pluginDirs.append(_pluginsDir)
+    module = None
     for dir in pluginDirs:
         try:
             files.extend(os.listdir(dir))
@@ -63,31 +82,36 @@ def loadPluginModule(name, ignoreDeprecation=False):
         if len(matched_names) >= 1:
             name = matched_names[0]
         else:
-            raise ImportError(name)
-
-    try:
-        if hasattr(importlib.util, 'module_from_spec'):
-            # Python >= 3.5
-            spec = importlib.machinery.PathFinder.find_spec(name, pluginDirs)
-            if spec is None or spec.loader is None:
-                # spec is None if 'name' can't be found; and
-                # spec.loader might be None in some rare occasions as well
-                # (eg. for namespace packages)
+            module = loadPluginFromEntrypoint(name)
+            if module is None:
                 raise ImportError(name)
-            module = importlib.util.module_from_spec(spec)
-            sys.modules[module.__name__] = module
-            spec.loader.exec_module(module)
-        else:
-            # Python < 3.5
-            moduleInfo = imp.find_module(name, pluginDirs)
-            module = imp.load_module(name, *moduleInfo)
-    except:
-        sys.modules.pop(name, None)
-        keys = list(sys.modules.keys())
-        for key in keys:
-            if key.startswith(name + '.'):
-                sys.modules.pop(key)
-        raise
+
+    if module is None:
+        # Found by listing files; must now import it
+        try:
+            if hasattr(importlib.util, 'module_from_spec'):
+                # Python >= 3.5
+                spec = importlib.machinery.PathFinder.find_spec(name, pluginDirs)
+                if spec is None or spec.loader is None:
+                    # spec is None if 'name' can't be found; and
+                    # spec.loader might be None in some rare occasions as well
+                    # (eg. for namespace packages)
+                    raise ImportError(name)
+                module = importlib.util.module_from_spec(spec)
+                sys.modules[module.__name__] = module
+                spec.loader.exec_module(module)
+            else:
+                # Python < 3.5
+                moduleInfo = imp.find_module(name, pluginDirs)
+                module = imp.load_module(name, *moduleInfo)
+        except:
+            sys.modules.pop(name, None)
+            keys = list(sys.modules.keys())
+            for key in keys:
+                if key.startswith(name + '.'):
+                    sys.modules.pop(key)
+            raise
+
     if 'deprecated' in module.__dict__ and module.deprecated:
         if ignoreDeprecation:
             log.warning('Deprecated plugin loaded: %s', name)

src/setup.py

@@ -0,0 +1,99 @@
+###
+# Copyright (c) 2020, Valentin Lorentz
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+#   * Redistributions of source code must retain the above copyright notice,
+#     this list of conditions, and the following disclaimer.
+#   * Redistributions in binary form must reproduce the above copyright notice,
+#     this list of conditions, and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#   * Neither the name of the author of this software nor the name of
+#     contributors to this software may be used to endorse or promote products
+#     derived from this software without specific prior written consent.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+###
+
+import os
+import sys
+
+try:
+    import setuptools
+except ImportError:
+    setuptools = None
+
+from . import authors
+
+if setuptools:
+    def plugin_setup(plugin, **kwargs):
+        """Wrapper of setuptools.setup that auto-fills some fields for
+        Limnoria plugins."""
+        if isinstance(plugin, str):
+            if plugin in sys.modules:
+                plugin = sys.modules[plugin]
+            else:
+                setup_path = sys.modules['__main__'].__file__
+                sys.path.insert(0, os.path.join(os.path.dirname(setup_path), '..'))
+                plugin = __import__(plugin)
+
+        author = plugin.__author__
+        version = plugin.__version__
+        url = plugin.__url__
+        maintainer = getattr(plugin, '__maintainer__', authors.unknown)
+
+        kwargs.setdefault('package_data', {}).setdefault('', []).append('*.po')
+
+        capitalized_name = plugin.Class.__name__
+        kwargs.setdefault(
+            'name', 'limnoria-%s' % capitalized_name.lower())
+        if version:
+            kwargs.setdefault('version', version)
+        if url:
+            kwargs.setdefault('url', url)
+
+        module_name = kwargs['name'].replace('-', '_')
+        kwargs.setdefault('packages', [module_name])
+        kwargs.setdefault('package_dir', {module_name: '.'})
+        kwargs.setdefault('entry_points', {
+            'limnoria.plugins': '%s = %s' % (capitalized_name, module_name)})
+
+        kwargs.setdefault('install_requires', []).append('limnoria')
+
+        kwargs.setdefault('classifiers', []).extend([
+            'Environment :: Plugins',
+            'Programming Language :: Python :: 3',
+            'Topic :: Communications :: Chat',
+        ])
+
+        if author is not authors.unknown:
+            if author.name or author.nick:
+                kwargs.setdefault('author', author.name or author.nick)
+            if author.email:
+                kwargs.setdefault('author_email', author.email)
+
+        if maintainer is not authors.unknown:
+            if maintainer.name or maintainer.nick:
+                kwargs.setdefault(
+                    'maintainer', maintainer.name or maintainer.nick)
+            if maintainer.email:
+                kwargs.setdefault('maintainer_email', maintainer.email)
+
+        setuptools.setup(
+            **kwargs)
+
+else:
+    def plugin_setup(plugin, **kwargs):
+        raise ImportError('setuptools')