Filtering always uses the "name" field

README.md

@@ -10,7 +10,9 @@ Metrics are selected using a [YAML configuration file](#Configuration).
 The exporter is available in two forms:
  - A [web application](#web-application) that you deploy to the server from which metrics are to be extracted.
  You may include a configuration file directly in the WAR file, and you may temporarily modify the configuration in a
- running system by using a web form. If a [coordination configurator](config_coordinator/README.md) is running and configured,
+ running system by using a web form, either by selecting a replacement configuration or one to append to the current one,
+ with the caveat that if both the original and appended configurations have filters, the update will be rejected. 
+ If a [coordination configurator](config_coordinator/README.md) is running and configured,
  that temporary configuration will be sent to all servers configured to use it.
 
  - A [separate process](#sidecar) that is run alongside a server instance. You supply the configuration to such a
@@ -288,7 +290,7 @@ vulnerability disclosure process.
 
 ## License
 
-Copyright (c) 2019, 2022 Oracle and/or its affiliates.
+Copyright (c) 2019, 2023, Oracle and/or its affiliates.
 
 Released under the Universal Permissive License v1.0 as shown at
 <https://oss.oracle.com/licenses/upl/>.

wls-exporter-core/src/main/java/com/oracle/wls/exporter/WlsRestExchanges.java

@@ -1,4 +1,4 @@
-// Copyright (c) 2021, 2022 Oracle and/or its affiliates.
+// Copyright (c) 2021, 2023, Oracle and/or its affiliates.
 // Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl.
 
 package com.oracle.wls.exporter;
@@ -8,13 +8,15 @@
 import java.util.Queue;
 import java.util.concurrent.ConcurrentLinkedDeque;
 
+import static java.time.format.DateTimeFormatter.ISO_LOCAL_TIME;
+
 /**
  * A diagnostic class that records requests sent to WLS and the replies received.
  */
 public class WlsRestExchanges {
 
   public static final int MAX_EXCHANGES = 5;
-  private static final String TEMPLATE = "REQUEST to %s:%n%s%nREPLY:%n%s%n";
+  private static final String TEMPLATE = "At %s, REQUEST to %s:%n%s%nREPLY:%n%s%n";
 
   private static final Queue<String> exchanges = new ConcurrentLinkedDeque<>();
 
@@ -35,10 +37,14 @@ public static List<String> getExchanges() {
    * @param response the returned JSON string
    */
   public static void addExchange(String url, String request, String response) {
-      exchanges.add(String.format(TEMPLATE, url, request, response));
+      exchanges.add(String.format(TEMPLATE, getCurrentTime(), url, request, response));
       if (exchanges.size() > MAX_EXCHANGES) exchanges.remove();
   }
 
+  private static String getCurrentTime() {
+    return ISO_LOCAL_TIME.format(SystemClock.now());
+  }
+
   /**
    * Clears the set of recorded exchanges. Intended for unit testing.
    */

wls-exporter-core/src/main/java/com/oracle/wls/exporter/domain/JsonQuerySpec.java

@@ -8,7 +8,6 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Objects;
 import java.util.Set;
 
 import com.google.gson.Gson;
@@ -30,13 +29,18 @@ class JsonQuerySpec {
     private List<String> selectedKeys = null;
     private List<String> excludeFields = null;
 
+    JsonQuerySpec asTopLevel() {
+        addFields();
+        return this;
+    }
+
     /**
      * Specifies the name of any mbean values which should be retrieved.
      * @param newFields the field names to add to any previous defined
      */
     void addFields(String... newFields) {
         if (fields == null) fields = new ArrayList<>();
-        Arrays.stream(newFields).filter(Objects::nonNull).forEach(fields::add);
+        fields.addAll(Arrays.asList(newFields));
     }
 
     /**
@@ -50,8 +54,8 @@ void addChild(String name, JsonQuerySpec child) {
         children.put(name, child);
     }
 
-    void setFilter(String keyName, Set<String> selectedKeys) {
-        this.keyName = keyName;
+    void setFilter(Set<String> selectedKeys) {
+        this.keyName = MBeanSelector.FILTER_KEY;
         this.selectedKeys = new ArrayList<>(selectedKeys);
     }
 

wls-exporter-core/src/main/java/com/oracle/wls/exporter/domain/MBeanSelector.java

@@ -44,6 +44,9 @@ public class MBeanSelector {
     static final String EXCLUDED_KEYS_KEY = "excludedKeyValues";
     static final String VALUES_KEY = "values";
     static final String STRING_VALUES_KEY = "stringValues";
+
+    /** The name of the field on which all runtime mbeans are filtered. **/
+    static final String FILTER_KEY = "name";
     static final String TYPE_FIELD_NAME = "type";
     static final MBeanSelector DOMAIN_NAME_SELECTOR = createDomainNameSelector();
     static final String NESTING = "  ";
@@ -105,7 +108,6 @@ private MBeanSelector(Map<String, Object> map) {
                     break;
             }
         }
-        validate();
     }
 
     private void addNestedSelector(String key, Object selectorValue) {
@@ -160,13 +162,6 @@ private void addStringValues(Object value) {
         }
     }
 
-    private void validate() {
-        if (getKey() == null && includedKeys != null)
-            throw new ConfigurationException("Included key values specified without key field");
-        if (getKey() == null && excludedKeys != null)
-            throw new ConfigurationException("Excluded key values specified without key field");
-    }
-
     /**
      * Appends a readable form of this selector as a YAML query to the specified string builder.
      * @param sb the string builder into which the selector should be added
@@ -361,7 +356,7 @@ JsonQuerySpec toQuerySpec() {
             selectQueryFields(spec, getQueryValues());
         }
         if (currentSelectorHasFilter() && !filter.isEmpty())
-            spec.setFilter(key, filter);
+            spec.setFilter(filter);
 
         for (Map.Entry<String, MBeanSelector> entry : nestedSelectors.entrySet())
             if (entry.getValue().isEnabled())
@@ -400,13 +395,13 @@ private void selectQueryFields(JsonQuerySpec spec, String[] fields) {
      * @return a JSON string
      */
     public String getKeyRequest() {
-        return toKeyQuerySpec().toJson(new Gson());
+        return toKeyQuerySpec().asTopLevel().toJson(new Gson());
     }
 
     JsonQuerySpec toKeyQuerySpec() {
         JsonQuerySpec spec = new JsonQuerySpec();
         if (currentSelectorHasFilter())
-            spec.addFields(key);
+            spec.addFields(FILTER_KEY);
         else
             spec.addFields();
 
@@ -480,8 +475,10 @@ private Stream<JsonElement> getItemsAsStream(JsonObject keyResponse, String subE
 
 
     private void acceptItem(JsonObject entry) {
-        final JsonElement keyElement = entry.get(key);
-        if (keyElement.isJsonPrimitive() && keyElement.getAsJsonPrimitive().isString()) {
+        final JsonElement keyElement = entry.get(FILTER_KEY);
+        if (keyElement == null)
+            offerKeys(entry);
+        else if (keyElement.isJsonPrimitive() && keyElement.getAsJsonPrimitive().isString()) {
             final String offeredKey = keyElement.getAsJsonPrimitive().getAsString();
             if (isSelectedKey(offeredKey)) {
                 filter.add(offeredKey);
@@ -512,12 +509,18 @@ MBeanSelector merge(MBeanSelector selector) {
     }
 
     private MBeanSelector(MBeanSelector first, MBeanSelector second) {
+        rejectConflicts(first, second);
         copyScalars(first);
         combineValues(first, second);
         combineStringValues(first, second);
         combineNestedSelectors(first, second);
     }
 
+    private void rejectConflicts(MBeanSelector first, MBeanSelector second) {
+        if (first.hasFilter() && second.hasFilter())
+            throw new ConfigurationException("May not merge configurations when both have filters.");
+    }
+
     private void copyScalars(MBeanSelector first) {
         this.type = first.type;
         this.prefix = first.prefix;