Remove CLI pkg_resources dependency

requirements.txt

@@ -4,4 +4,5 @@ colorama
 requests>=2.2.1
 XlsxWriter
 ipaddress;python_version<='2.7'
-tldextract
+importlib-metadata;python_version<'3.8'
+tldextract

shodan/__main__.py

@@ -30,14 +30,18 @@
 import csv
 import os
 import os.path
-import pkg_resources
 import shodan
 import shodan.helpers as helpers
 import threading
 import requests
 import time
 import json
 
+try:
+    from importlib.metadata import entry_points, version as package_version
+except ImportError:
+    from importlib_metadata import entry_points, version as package_version
+
 # The file converters that are used to go from .json.gz to various other formats
 from shodan.cli.converter import CsvConverter, KmlConverter, GeoJsonConverter, ExcelConverter, ImagesConverter
 
@@ -50,7 +54,6 @@
 
 # Allow 3rd-parties to develop custom commands
 from click_plugins import with_plugins
-from pkg_resources import iter_entry_points
 
 # Large subcommands are stored in separate modules
 from shodan.cli.alert import alert
@@ -76,9 +79,16 @@
     basestring = str
 
 
+def iter_plugin_entry_points(group):
+    discovered = entry_points()
+    if isinstance(discovered, dict):
+        return discovered.get(group, ())
+    return discovered.select(group=group)
+
+
 # Define the main entry point for all of our commands
 # and expose a way for 3rd-party plugins to tie into the Shodan CLI.
-@with_plugins(iter_entry_points('shodan.cli.plugins'))
+@with_plugins(iter_plugin_entry_points('shodan.cli.plugins'))
 @click.group(context_settings=CONTEXT_SETTINGS)
 def main():
     pass
@@ -942,7 +952,7 @@ def radar():
 @main.command()
 def version():
     """Print version of this tool."""
-    print(pkg_resources.get_distribution("shodan").version)
+    print(package_version('shodan'))
 
 
 if __name__ == '__main__':

tests/test_cli.py

@@ -0,0 +1,61 @@
+import importlib
+import sys
+import unittest
+from types import ModuleType
+from unittest import mock
+
+from click.testing import CliRunner
+
+
+class CliTests(unittest.TestCase):
+
+    def test_plugins_load_from_legacy_entry_point_mapping(self):
+        # Given the mapping returned by older importlib-metadata releases
+        cli = importlib.import_module('shodan.__main__')
+        plugin = object()
+
+        with mock.patch('shodan.__main__.entry_points', return_value={'shodan.cli.plugins': (plugin,)}):
+            # When the CLI discovers third-party plugins
+            plugins = tuple(cli.iter_plugin_entry_points('shodan.cli.plugins'))
+
+        # Then it returns the entries for the requested group
+        self.assertEqual((plugin,), plugins)
+
+    def test_version_reports_installed_distribution(self):
+        # Given the installed Shodan CLI
+        cli = importlib.import_module('shodan.__main__')
+
+        # When its version command is invoked
+        result = CliRunner().invoke(cli.main, ['version'])
+
+        # Then it reports the installed distribution version
+        self.assertEqual(0, result.exit_code, result.output)
+        self.assertRegex(result.output.strip(), r'^\d+\.\d+\.\d+$')
+
+    def test_help_renders_without_pkg_resources(self):
+        # Given an isolated runtime where pkg_resources is unavailable
+        previous = sys.modules.get('pkg_resources')
+        sys.modules['pkg_resources'] = ModuleType('pkg_resources')
+        sys.modules.pop('shodan.__main__', None)
+
+        try:
+            # When the CLI is imported and asked to render help
+            try:
+                cli = importlib.import_module('shodan.__main__')
+            except ImportError as exc:
+                self.fail('CLI import should not require pkg_resources: {}'.format(exc))
+            result = CliRunner().invoke(cli.main, ['--help'])
+        finally:
+            sys.modules.pop('shodan.__main__', None)
+            if previous is not None:
+                sys.modules['pkg_resources'] = previous
+            else:
+                sys.modules.pop('pkg_resources', None)
+
+        # Then help renders successfully through the real Click command
+        self.assertEqual(0, result.exit_code, result.output)
+        self.assertIn('Usage:', result.output)
+
+
+if __name__ == '__main__':
+    unittest.main()