replacing pkg_resources with importlib (#3749)

Fixes #3743

nikola/nikola.py

@@ -46,7 +46,6 @@
 import lxml.html
 import natsort
 import PyRSS2Gen as rss
-from pkg_resources import resource_filename
 from blinker import signal
 
 from . import DEBUG, SHOW_TRACEBACKS, filters, utils, hierarchy_utils, shortcodes
@@ -1031,7 +1030,7 @@ def init_plugins(self, commands_only=False, load_all=False):
         extra_plugins_dirs = self.config['EXTRA_PLUGINS_DIRS']
         self._loading_commands_only = commands_only
         self._plugin_places = [
-            resource_filename('nikola', 'plugins'),
+            utils.pkg_resources_path('nikola', 'plugins'),
             os.path.expanduser(os.path.join('~', '.nikola', 'plugins')),
             os.path.join(os.getcwd(), 'plugins'),
         ] + [path for path in extra_plugins_dirs if path]
@@ -1694,7 +1693,7 @@ def _register_templated_shortcodes(self):
         """
         self.register_shortcode('template', self._template_shortcode_handler)
 
-        builtin_sc_dir = resource_filename(
+        builtin_sc_dir = utils.pkg_resources_path(
             'nikola',
             os.path.join('data', 'shortcodes', utils.get_template_engine(self.THEMES)))
 

nikola/plugins/basic_import.py

@@ -34,7 +34,6 @@
 
 from lxml import etree, html
 from mako.template import Template
-from pkg_resources import resource_filename
 
 from nikola import utils
 
@@ -98,7 +97,7 @@ def generate_base_site(self):
             utils.LOGGER.warning('The folder {0} already exists - assuming that this is a '
                                  'already existing Nikola site.'.format(self.output_folder))
 
-        filename = resource_filename('nikola', 'conf.py.in')
+        filename = utils.pkg_resources_path('nikola', 'conf.py.in')
         # The 'strict_undefined=True' will give the missing symbol name if any,
         # (ex: NameError: 'THEME' is not defined )
         # for other errors from mako/runtime.py, you can add format_extensions=True ,

nikola/plugins/command/auto/__init__.py

@@ -40,10 +40,9 @@
 from pathlib import Path
 
 import blinker
-import pkg_resources
 
 from nikola.plugin_categories import Command
-from nikola.utils import dns_sd, req_missing, get_theme_path, makedirs
+from nikola.utils import dns_sd, req_missing, get_theme_path, makedirs, pkg_resources_path
 
 try:
     import aiohttp
@@ -221,7 +220,7 @@ def _execute(self, options, args):
             watched.add(item)
         watched |= self.site.registered_auto_watched_folders
         # Nikola itself (useful for developers)
-        watched.add(pkg_resources.resource_filename('nikola', ''))
+        watched.add(pkg_resources_path('nikola', ''))
 
         out_folder = self.site.config['OUTPUT_FOLDER']
         if not os.path.exists(out_folder):

nikola/plugins/command/init.py

@@ -38,12 +38,11 @@
 import dateutil.tz
 import dateutil.zoneinfo
 from mako.template import Template
-from pkg_resources import resource_filename
 
 import nikola
 from nikola.nikola import DEFAULT_INDEX_READ_MORE_LINK, DEFAULT_FEED_READ_MORE_LINK, LEGAL_VALUES
 from nikola.plugin_categories import Command
-from nikola.utils import ask, ask_yesno, get_logger, makedirs, load_messages
+from nikola.utils import ask, ask_yesno, get_logger, makedirs, load_messages, pkg_resources_path
 from nikola.packages.tzlocal import get_localzone
 
 
@@ -273,13 +272,13 @@ class CommandInit(Command):
     @classmethod
     def copy_sample_site(cls, target):
         """Copy sample site data to target directory."""
-        src = resource_filename('nikola', os.path.join('data', 'samplesite'))
+        src = pkg_resources_path('nikola', os.path.join('data', 'samplesite'))
         shutil.copytree(src, target)
 
     @staticmethod
     def create_configuration(target):
         """Create configuration file."""
-        template_path = resource_filename('nikola', 'conf.py.in')
+        template_path = pkg_resources_path('nikola', 'conf.py.in')
         conf_template = Template(filename=template_path)
         conf_path = os.path.join(target, 'conf.py')
         with io.open(conf_path, 'w+', encoding='utf8') as fd:
@@ -288,7 +287,7 @@ def create_configuration(target):
     @staticmethod
     def create_configuration_to_string():
         """Return configuration file as a string."""
-        template_path = resource_filename('nikola', 'conf.py.in')
+        template_path = pkg_resources_path('nikola', 'conf.py.in')
         conf_template = Template(filename=template_path)
         return conf_template.render(**prepare_config(SAMPLE_CONF))
 

nikola/plugins/command/rst2html/__init__.py

@@ -29,9 +29,9 @@
 
 import io
 import lxml.html
-from pkg_resources import resource_filename
 from mako.template import Template
 from nikola.plugin_categories import Command
+from nikola.utils import pkg_resources_path
 
 
 class CommandRst2Html(Command):
@@ -53,11 +53,11 @@ def _execute(self, options, args):
             data = in_file.read()
             output, error_level, deps, shortcode_deps = compiler.compile_string(data, source, True)
 
-        rstcss_path = resource_filename('nikola', 'data/themes/base/assets/css/rst_base.css')
+        rstcss_path = pkg_resources_path('nikola', 'data/themes/base/assets/css/rst_base.css')
         with io.open(rstcss_path, "r", encoding="utf-8-sig") as fh:
             rstcss = fh.read()
 
-        template_path = resource_filename('nikola', 'plugins/command/rst2html/rst2html.tmpl')
+        template_path = pkg_resources_path('nikola', 'plugins/command/rst2html/rst2html.tmpl')
         template = Template(filename=template_path)
         template_output = template.render(rstcss=rstcss, output=output)
         parser = lxml.html.HTMLParser(remove_blank_text=True)

nikola/plugins/command/theme.py

@@ -38,7 +38,6 @@
 import pygments
 from pygments.lexers import PythonLexer
 from pygments.formatters import TerminalFormatter
-from pkg_resources import resource_filename
 
 from nikola.plugin_categories import Command
 from nikola import utils
@@ -287,7 +286,7 @@ def list_installed(self):
         print("Installed Themes:")
         print("-----------------")
         themes = []
-        themes_dirs = self.site.themes_dirs + [resource_filename('nikola', os.path.join('data', 'themes'))]
+        themes_dirs = self.site.themes_dirs + [utils.pkg_resources_path('nikola', os.path.join('data', 'themes'))]
         for tdir in themes_dirs:
             if os.path.isdir(tdir):
                 themes += [(i, os.path.join(tdir, i)) for i in os.listdir(tdir)]

nikola/utils.py

@@ -60,7 +60,6 @@
 from blinker import signal
 from doit import tools
 from doit.cmdparse import CmdParse
-from pkg_resources import resource_filename
 from nikola.packages.pygments_better_html import BetterHtmlFormatter
 from typing import List
 from unidecode import unidecode
@@ -71,6 +70,11 @@
 from .hierarchy_utils import TreeNode, clone_treenode, flatten_tree_structure, sort_classifications
 from .hierarchy_utils import join_hierarchical_category_path, parse_escaped_hierarchical_category_name
 
+if sys.version_info.minor <= 8:
+    from pkg_resources import resource_filename
+else:
+    from importlib import resources
+
 try:
     import toml
 except ImportError:
@@ -577,6 +581,14 @@ def __repr__(self):
                                                            sort_keys=True))
 
 
+def pkg_resources_path(package, resource):
+    """Return path to a resource from the package with the given name."""
+    if sys.version_info.minor <= 8:
+        return resource_filename(package, resource)
+    else:
+        return str(resources.files(package).joinpath(resource))
+
+
 def get_theme_path_real(theme, themes_dirs):
     """Return the path where the given theme's files are located.
 
@@ -586,7 +598,7 @@ def get_theme_path_real(theme, themes_dirs):
         dir_name = os.path.join(themes_dir, theme)
         if os.path.isdir(dir_name):
             return dir_name
-    dir_name = resource_filename('nikola', os.path.join('data', 'themes', theme))
+    dir_name = pkg_resources_path('nikola', os.path.join('data', 'themes', theme))
     if os.path.isdir(dir_name):
         return dir_name
     raise Exception("Can't find theme '{0}'".format(theme))