Merge pull request 'feat(ext-openapi): a route can say it is not part of the API' (#23) from feat/openapi/undocumented into master

flash-extensions/flash-ext-openapi/README.md

@@ -33,6 +33,18 @@ Every class-based route is documented, annotated or not. Read off the code:
 
 Annotations add what the code cannot say: prose, extra statuses, examples. They never repeat it.
 
+## Leaving a route out
+
+```java
+@GET("/healthz")
+@Undocumented
+public final class Health extends RequestHandler { ... }
+```
+
+Every route is documented, so a document never lies by omission. `@Undocumented` says a route is
+not part of the API — a health check, an internal callback, something on its way out. On a base
+class it leaves out every handler written against it.
+
 ## Request bodies
 
 A handler that extends `BodyHandler` — `JsonHandler` and `XmlHandler`, and anything else that

flash-extensions/flash-ext-openapi/src/main/java/dev/relism/flash/ext/openapi/OpenApiBuilder.java

@@ -65,8 +65,13 @@ public final class OpenApiBuilder {
     public OpenApiBuilder description(String description) { this.description = description; return this; }
     void setContributorRegistry(OpenApiContributorRegistry registry) { this.contributorRegistry = registry; }
 
-    /** Documents one route. {@code op} is optional: a route without it is still an operation. */
+    /**
+     * Documents one route. {@code op} is optional: a route without it is still an operation.
+     * A handler marked {@link Undocumented} is left out entirely.
+     */
     public void addOperation(Route route, ApiOperation op, Class<?> handlerClass) {
+        if (handlerClass.isAnnotationPresent(Undocumented.class)) return;
+
         String path = normalizePath(route.path());
         String method = route.method().name().toLowerCase(Locale.ROOT);
 

flash-extensions/flash-ext-openapi/src/main/java/dev/relism/flash/ext/openapi/Undocumented.java

@@ -0,0 +1,21 @@
+package dev.relism.flash.ext.openapi;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Inherited;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Keeps a route out of the published document.
+ *
+ * <p>Every class-based route is documented, which is what stops a document from lying by
+ * omission. Some routes are not part of the API anyway — a health check, an internal callback,
+ * something on its way out — and this says so, once, where the handler is.
+ *
+ * <p>Inherited: on a base class it leaves out every handler written against it.
+ */
+@Inherited
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.TYPE)
+public @interface Undocumented {}

flash-extensions/flash-ext-openapi/src/test/java/dev/relism/flash/ext/openapi/OpenApiBuilderTest.java

@@ -220,6 +220,24 @@ class OpenApiBuilderTest {
         assertEquals("array", schema.get("type"));
     }
 
+    @GET("/internal")
+    @Undocumented
+    static class InternalHandler extends RequestHandler {
+        @Override public Object handle(Request request, Response response) { return null; }
+    }
+
+    @Test
+    void a_route_that_says_it_is_not_part_of_the_api_is_left_out() {
+        OpenApiBuilder b = new OpenApiBuilder();
+        b.addOperation(OpenApiBuilder.routeOf(InternalHandler.class), null, InternalHandler.class);
+        b.addOperation(OpenApiBuilder.routeOf(BareHandler.class), null, BareHandler.class);
+
+        Map<String, Object> paths = cast(b.build().get("paths"));
+
+        assertFalse(paths.containsKey("/internal"));
+        assertTrue(paths.containsKey("/bare"), "the others are still documented");
+    }
+
     @Test
     void a_route_with_no_annotations_is_still_documented() {
         OpenApiBuilder b = new OpenApiBuilder();