Add methods to clear PluginMetadata repositories

robbavey · robbavey · commit 2e2a00270e9d · 2019-04-26T13:15:46.000Z
Fixes #10691
diff --git a/logstash-core/lib/logstash/plugin_metadata.rb b/logstash-core/lib/logstash/plugin_metadata.rb
@@ -21,13 +21,14 @@ module LogStash
   # that doesn't break when installed onto a Logstash that doesn't have those features, e.g.:
   #
   # ~~~
-  # if defined?(LogStash::PluginMetadata)
-  #   LogStash::PluginMetadata.set(id, :foo, bar)
-  # end
+  #
+  # plugin_metadata.set(:foo, bar) if defined?(plugin_metadata?)
+  #
   # ~~~
   #
   # @since 7.1
   class PluginMetadata
+
     Thread.exclusive do
       @registry = ThreadSafe::Cache.new unless defined?(@registry)
     end
@@ -55,6 +56,17 @@ def exists?(plugin_id)
         @registry.key?(plugin_id)
       end
 
+      ##
+      # Deletes, and then clears the contents of an existing PluginMetadata object for the given plugin id if one exists
+      #
+      # @param plugin_id [String]
+      #
+      # @return [Boolean]
+      def delete_for_plugin(plugin_id)
+        old_registry = @registry.delete(plugin_id)
+        old_registry.clear unless old_registry.nil?
+      end
+
       ##
       # @api private
       def reset!
@@ -104,5 +116,23 @@ def get(key)
     def set?(key)
       @datastore.key?(key)
     end
+
+    ##
+    # Delete the metadata key for this plugin, returning the previous value (if any)
+    #
+    # @param key [Symbol]
+    #
+    # @return [Object]
+    def delete(key)
+      @datastore.delete(key)
+    end
+
+    ##
+    # Clear all metadata keys for this plugin
+    #
+    # @return [Object]
+    def clear
+      @datastore.clear
+    end
   end
 end
diff --git a/logstash-core/spec/logstash/plugin_spec.rb b/logstash-core/spec/logstash/plugin_spec.rb
@@ -312,6 +312,10 @@ def register; end
               expect(plugin_instance.plugin_metadata).to be_a_kind_of(LogStash::PluginMetadata)
             end
 
+            it "PluginMetadata is defined" do
+              expect(defined?(plugin_instance.plugin_metadata)).to be_truthy
+            end
+
             if config_override.include?('id')
               it "will be shared between instance of plugins" do
                 expect(plugin_instance.plugin_metadata).to equal(plugin.new(config).plugin_metadata)
diff --git a/logstash-core/spec/plugin_metadata_spec.rb b/logstash-core/spec/plugin_metadata_spec.rb
@@ -33,6 +33,20 @@
         end
       end
     end
+    describe '#delete_for_plugin' do
+      before(:each) { registry.for_plugin(plugin_id).set(:foo, 'bar') }
+      it 'deletes the registry' do
+        expect(registry.exists?(plugin_id)).to be true
+        registry.delete_for_plugin(plugin_id)
+        expect(registry.exists?(plugin_id)).to be false
+      end
+      it 'deletes the data inside the registry' do
+        plugin_registry = registry.for_plugin(plugin_id)
+        registry.delete_for_plugin(plugin_id)
+        expect(plugin_registry.set?(:foo)).to be false
+      end
+    end
+
   end
 
   describe 'instance' do
@@ -49,14 +63,15 @@
         end
       end
       context 'when the key is set' do
-        before(:each) { instance.set(:foo, 'bananas') }
+        let (:val) { 'bananas'}
+        before(:each) { instance.set(:foo, val) }
 
         it 'sets the new value' do
           instance.set(:foo, 'bar')
           expect(instance.get(:foo)).to eq('bar')
         end
         it 'returns the previous associated value' do
-          expect(instance.set(:foo, 'bar')).to eq('bananas')
+          expect(instance.set(:foo, 'bar')).to eq(val)
         end
         context 'when the new value is nil' do
           it 'unsets the value' do
@@ -94,5 +109,43 @@
         end
       end
     end
+
+    describe '#delete' do
+      context 'when the key is set' do
+        let (:val) { 'bananas' }
+        before(:each) { instance.set(:foo, val)}
+        it 'returns the value' do
+          expect(instance.delete(:foo)).to be val
+        end
+        it 'removes the key' do
+          instance.delete(:foo)
+          expect(instance.set?(:foo)).to be false
+        end
+      end
+      context 'when the key is not set' do
+        it 'returns nil' do
+          expect(instance.delete(:foo)).to be nil
+        end
+
+        it 'should not be set' do
+          instance.delete(:foo)
+          expect(instance.set?(:foo)).to be false
+        end
+      end
+    end
+
+    describe '#clear' do
+      context 'when the key is set' do
+        before(:each) do
+          instance.set(:foo, 'bananas')
+          instance.set(:bar, 'more bananas')
+        end
+        it 'removes all keys' do
+          instance.clear
+          expect(instance.set?(:foo)).to be false
+          expect(instance.set?(:bar)).to be false
+        end
+      end
+    end
   end
 end
