CFINSPEC-533: Fix undefined method 'summary' for Gem::SourceFetchProblem (NoMethodError) when airgapped (#6337) (#6434)

* This fixes the undefined method 'summary' for #<Gem::SourceFetchProblem:0x000000000139dc70> (NoMethodError) while invoking any inspec command if the custom plugin is installed and if inspec commands are run in an air gap environment.
This fix removes an earlier call for getting gem specification from rubygems.org which is the cause for above error and replaces it with fetching the summary from a locally saved gemspec file. This will work in both airgap and non-airgap environments.



* Adds test for reading description from local gemspec file.

Signed-off-by: Vasu1105 <vasundhara.jagdale@chef.io>

lib/inspec/plugin/v2/loader.rb

@@ -290,7 +290,12 @@ module Inspec::Plugin::V2
         when :user_gem
           status.entry_point = status.name.to_s
           status.version = plugin_entry[:version]
-          status.description = fetch_plugin_specs(status.name.to_s)&.summary
+          # Fetch the summary of the gem from local gemspec file instead of remote call using Gem::SpecFetcher.fetcher.
+          unless plugin_entry[:version].nil? # safe check very rare case.
+            version_string = plugin_entry[:version].gsub(/[=,~,>,<]/, "").strip
+            plugin_name_with_version = "#{status.name}-#{version_string}"
+            status.description = fetch_gemspec(File.join(plugin_gem_path, "gems", plugin_name_with_version, "/", status.name.to_s + ".gemspec"))&.summary
+          end
         when :path
           status.entry_point = plugin_entry[:installation_path]
         end
@@ -299,12 +304,6 @@ module Inspec::Plugin::V2
       end
     end
 
-    def fetch_plugin_specs(plugin_name)
-      fetcher = Gem::SpecFetcher.fetcher
-      plugin_dependency = Gem::Dependency.new(plugin_name)
-      fetcher.spec_for_dependency(plugin_dependency).flatten.first
-    end
-
     def fixup_train_plugin_status(status)
       status.api_generation = :'train-1'
       if status.installation_type == :user_gem

test/artifact/inspec_plugin_test.rb

@@ -5,7 +5,6 @@ class TestInspecPlugin < ArtifactTest
     # This one is custom because it emits a special warning to stderr
     inspec_command = "plugin list"
     stdout, stderr, status = run_cmd "inspec #{inspec_command} #{TEST_CLI_OPTS}"
-
     assert_empty stderr.sub(/#< CLIXML\n/, "").sub(/The table size exceeds the currently set width\.Defaulting to vertical orientation\.\n/, "")
     assert stdout
     assert status

test/fixtures/config_dirs/train-test-fixture/plugins.json

@@ -3,7 +3,7 @@
   "plugins": [
     {
       "name": "train-test-fixture",
-      "version": "0.1.0"
+      "version": ">= 0.1.0"
     }
   ]
 }

test/unit/plugin/v2/loader_test.rb

@@ -333,4 +333,14 @@ class PluginLoaderTests < Minitest::Test
       end
     end
   end
+
+  def test_read_conf_file_into_registry
+    ENV["INSPEC_CONFIG_DIR"] = File.join(@config_dir_path, "train-test-fixture")
+    loader = Inspec::Plugin::V2::Loader.new(omit_bundles: true)
+    registry = loader.send(:read_conf_file_into_registry)
+    assert_includes registry, { :name => :"train-test-fixture", :version => ">= 0.1.0" }
+    reg = Inspec::Plugin::V2::Registry.instance
+    status = reg[registry.first[:name]]
+    assert_equal("Test train plugin. Not intended for use as an example.", status.description, "Reads the description of the plugin from local gemspec file.")
+  end
 end