1 files changed, 36 insertions, 0 deletions
diff --git a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/http/HttpHandlerBase.java b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/http/HttpHandlerBase.java
index d3643bd8e61..d582abdba57 100644
--- a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/http/HttpHandlerBase.java
+++ b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/http/HttpHandlerBase.java
@@ -11,14 +11,21 @@ import com.yahoo.container.jdisc.HttpRequest;
 import com.yahoo.container.jdisc.HttpResponse;
 import com.yahoo.container.jdisc.ThreadedHttpRequestHandler;
 import com.yahoo.restapi.Path;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
 
 import java.net.URI;
+import java.util.List;
 import java.util.Optional;
 import java.util.concurrent.Executor;
 
+import static com.yahoo.jdisc.Response.Status.INTERNAL_SERVER_ERROR;
 import static com.yahoo.jdisc.Response.Status.METHOD_NOT_ALLOWED;
 import static com.yahoo.jdisc.Response.Status.NOT_FOUND;
+import static com.yahoo.jdisc.Response.Status.OK;
 import static com.yahoo.jdisc.http.HttpRequest.Method.GET;
+import static java.util.logging.Level.WARNING;
 
 /**
  * @author gjoranv
@@ -51,4 +58,33 @@ public abstract class HttpHandlerBase extends ThreadedHttpRequestHandler {
         return request.getProperty("consumer");
     }
 
+    protected JsonResponse resourceListResponse(URI requestUri, List<String> resources) {
+        try {
+            return new JsonResponse(OK, resourceList(requestUri, resources));
+        } catch (JSONException e) {
+            log.log(WARNING, "Bad JSON construction in generated resource list for " + requestUri.getPath(), e);
+            return new ErrorResponse(INTERNAL_SERVER_ERROR,
+                                     "An error occurred when generating the list of api resources.");
+        }
+    }
+
+    // TODO: Use jackson with a "Resources" class instead of JSONObject
+    private static String resourceList(URI requestUri, List<String> resources) throws JSONException {
+        int port = requestUri.getPort();
+        String host = requestUri.getHost();
+        StringBuilder base = new StringBuilder("http://");
+        base.append(host);
+        if (port >= 0) {
+            base.append(":").append(port);
+        }
+        String uriBase = base.toString();
+        JSONArray linkList = new JSONArray();
+        for (String api : resources) {
+            JSONObject resource = new JSONObject();
+            resource.put("url", uriBase + api);
+            linkList.put(resource);
+        }
+        return new JSONObject().put("resources", linkList).toString(4);
+    }
+
 }