Add a separate construct in ModelContext.Properties for feature flags

2 files changed, 52 insertions, 0 deletions

diff --git a/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java b/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
index 2e78da0dc91..ab6a6660ebe 100644
--- a/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
+++ b/config-model-api/src/main/java/com/yahoo/config/model/api/ModelContext.java
@@ -12,6 +12,10 @@ import com.yahoo.config.provision.HostName;
 import com.yahoo.config.provision.Zone;
 
 import java.io.File;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 import java.net.URI;
 import java.time.Duration;
 import java.util.List;
@@ -45,8 +49,13 @@ public interface ModelContext {
     /** The Vespa version we want nodes to become */
     Version wantedNodeVespaVersion();
 
+    interface FeatureFlags {
+
+    }
+
     /** Warning: As elsewhere in this package, do not make backwards incompatible changes that will break old config models! */
     interface Properties {
+        FeatureFlags featureFlags();
         boolean multitenant();
         ApplicationId applicationId();
         List<ConfigServerSpec> configServerSpecs();
@@ -135,4 +144,11 @@ public interface ModelContext {
 
     }
 
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(ElementType.METHOD)
+    @interface ModelFeatureFlag {
+        String owner();
+        String comment() default "";
+    }
+
 }
diff --git a/config-model-api/src/test/java/com/yahoo/config/model/api/ModelContextTest.java b/config-model-api/src/test/java/com/yahoo/config/model/api/ModelContextTest.java
new file mode 100644
index 00000000000..68b6b9f814f
--- /dev/null
+++ b/config-model-api/src/test/java/com/yahoo/config/model/api/ModelContextTest.java
@@ -0,0 +1,36 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.model.api;
+
+import org.junit.Test;
+
+import java.lang.reflect.Method;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author bjorncs
+ */
+public class ModelContextTest {
+
+    @Test
+    public void verify_all_feature_flag_methods_have_annotation() {
+        for (Method method : ModelContext.FeatureFlags.class.getDeclaredMethods()) {
+            assertNotNull(
+                    String.format(
+                            "Method '%s' is not annotated with '%s'",
+                            method.getName(), ModelContext.ModelFeatureFlag.class.getSimpleName()),
+                    method.getDeclaredAnnotation(ModelContext.ModelFeatureFlag.class));
+        }
+    }
+
+    @Test
+    public void verify_all_feature_flag_methods_have_default_implementation() {
+        for (Method method : ModelContext.FeatureFlags.class.getDeclaredMethods()) {
+            assertTrue(
+                    String.format("Method '%s' has no default implementation", method.getName()),
+                    method.isDefault());
+        }
+    }
+
+}
\ No newline at end of file