Create set-based interface for NodesInfoRequest (#53410)

This commit begins the work of removing the "hard-coded" metric getters
and setters from the NodesInfoRequest classes. We start by providing new
flexible getters and setters. We then update the test classes to remove
the old getters, and then remove those getters.

Author: williamrandolph

server/src/main/java/org/elasticsearch/action/admin/cluster/node/info/NodesInfoRequest.java

@@ -27,14 +27,16 @@
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Set;
+import java.util.SortedSet;
+import java.util.TreeSet;
 import java.util.stream.Collectors;
 
 /**
  * A request to get node (cluster) level information.
  */
 public class NodesInfoRequest extends BaseNodesRequest<NodesInfoRequest> {
 
-    private Set<String> requestedMetrics = Metrics.allMetrics();
+    private Set<String> requestedMetrics = Metric.allMetrics();
 
     /**
      * Create a new NodeInfoRequest from a {@link StreamInput} object.
@@ -48,16 +50,16 @@ public NodesInfoRequest(StreamInput in) throws IOException {
         if (in.getVersion().before(Version.V_7_7_0)){
             // prior to version 8.x, a NodesInfoRequest was serialized as a list
             // of booleans in a fixed order
-            addOrRemoveMetric(in.readBoolean(), Metrics.SETTINGS.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.OS.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.PROCESS.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.JVM.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.THREAD_POOL.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.TRANSPORT.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.HTTP.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.PLUGINS.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.INGEST.metricName());
-            addOrRemoveMetric(in.readBoolean(), Metrics.INDICES.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.SETTINGS.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.OS.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.PROCESS.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.JVM.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.THREAD_POOL.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.TRANSPORT.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.HTTP.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.PLUGINS.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.INGEST.metricName());
+            optionallyAddMetric(in.readBoolean(), Metric.INDICES.metricName());
         } else {
             requestedMetrics.addAll(Arrays.asList(in.readStringArray()));
         }
@@ -84,174 +86,63 @@ public NodesInfoRequest clear() {
      * Sets to return all the data.
      */
     public NodesInfoRequest all() {
-        requestedMetrics.addAll(Metrics.allMetrics());
+        requestedMetrics.addAll(Metric.allMetrics());
         return this;
     }
 
     /**
-     * Should the node settings be returned.
+     * Get the names of requested metrics
      */
-    public boolean settings() {
-        return Metrics.SETTINGS.containedIn(requestedMetrics);
+    public Set<String> requestedMetrics() {
+        return Set.copyOf(requestedMetrics);
     }
 
     /**
-     * Should the node settings be returned.
+     * Add metric
      */
-    public NodesInfoRequest settings(boolean settings) {
-        addOrRemoveMetric(settings, Metrics.SETTINGS.metricName());
-        return this;
-    }
-
-    /**
-     * Should the node OS be returned.
-     */
-    public boolean os() {
-        return Metrics.OS.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Should the node OS be returned.
-     */
-    public NodesInfoRequest os(boolean os) {
-        addOrRemoveMetric(os, Metrics.OS.metricName());
-        return this;
-    }
-
-    /**
-     * Should the node Process be returned.
-     */
-    public boolean process() {
-        return Metrics.PROCESS.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Should the node Process be returned.
-     */
-    public NodesInfoRequest process(boolean process) {
-        addOrRemoveMetric(process, Metrics.PROCESS.metricName());
-        return this;
-    }
-
-    /**
-     * Should the node JVM be returned.
-     */
-    public boolean jvm() {
-        return Metrics.JVM.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Should the node JVM be returned.
-     */
-    public NodesInfoRequest jvm(boolean jvm) {
-        addOrRemoveMetric(jvm, Metrics.JVM.metricName());
-        return this;
-    }
-
-    /**
-     * Should the node Thread Pool info be returned.
-     */
-    public boolean threadPool() {
-        return Metrics.THREAD_POOL.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Should the node Thread Pool info be returned.
-     */
-    public NodesInfoRequest threadPool(boolean threadPool) {
-        addOrRemoveMetric(threadPool, Metrics.THREAD_POOL.metricName());
-        return this;
-    }
-
-    /**
-     * Should the node Transport be returned.
-     */
-    public boolean transport() {
-        return Metrics.TRANSPORT.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Should the node Transport be returned.
-     */
-    public NodesInfoRequest transport(boolean transport) {
-        addOrRemoveMetric(transport, Metrics.TRANSPORT.metricName());
-        return this;
-    }
-
-    /**
-     * Should the node HTTP be returned.
-     */
-    public boolean http() {
-        return Metrics.HTTP.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Should the node HTTP be returned.
-     */
-    public NodesInfoRequest http(boolean http) {
-        addOrRemoveMetric(http, Metrics.HTTP.metricName());
-        return this;
-    }
-
-    /**
-     * Should information about plugins be returned
-     * @param plugins true if you want info
-     * @return The request
-     */
-    public NodesInfoRequest plugins(boolean plugins) {
-        addOrRemoveMetric(plugins, Metrics.PLUGINS.metricName());
+    public NodesInfoRequest addMetric(String metric) {
+        if (Metric.allMetrics().contains(metric) == false) {
+            throw new IllegalStateException("Used an illegal metric: " + metric);
+        }
+        requestedMetrics.add(metric);
         return this;
     }
 
     /**
-     * @return true if information about plugins is requested
-     */
-    public boolean plugins() {
-        return Metrics.PLUGINS.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Should information about ingest be returned
-     * @param ingest true if you want info
+     * Add multiple metrics
      */
-    public NodesInfoRequest ingest(boolean ingest) {
-        addOrRemoveMetric(ingest, Metrics.INGEST.metricName());
+    public NodesInfoRequest addMetrics(String... metrics) {
+        SortedSet<String> metricsSet = new TreeSet<>(Set.of(metrics));
+        if (Metric.allMetrics().containsAll(metricsSet) == false) {
+            metricsSet.removeAll(Metric.allMetrics());
+            String plural = metricsSet.size() == 1 ? "" : "s";
+            throw new IllegalStateException("Used illegal metric" + plural + ": " + metricsSet);
+        }
+        requestedMetrics.addAll(metricsSet);
         return this;
     }
 
     /**
-     * @return true if information about ingest is requested
+     * Remove metric
      */
-    public boolean ingest() {
-        return Metrics.INGEST.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Should information about indices (currently just indexing buffers) be returned
-     * @param indices true if you want info
-     */
-    public NodesInfoRequest indices(boolean indices) {
-        addOrRemoveMetric(indices, Metrics.INDICES.metricName());
+    public NodesInfoRequest removeMetric(String metric) {
+        if (Metric.allMetrics().contains(metric) == false) {
+            throw new IllegalStateException("Used an illegal metric: " + metric);
+        }
+        requestedMetrics.remove(metric);
         return this;
     }
 
     /**
-     * @return true if information about indices (currently just indexing buffers)
-     */
-    public boolean indices() {
-        return Metrics.INDICES.containedIn(requestedMetrics);
-    }
-
-    /**
-     * Helper method for adding and removing metrics.
-     * @param includeMetric Whether or not to include a metric.
+     * Helper method for adding and removing metrics. Used when deserializing
+     * a NodesInfoRequest from an ordered list of booleans.
+     *
+     * @param addMetric Whether or not to include a metric.
      * @param metricName Name of the metric to include or remove.
      */
-    private void addOrRemoveMetric(boolean includeMetric, String metricName) {
-        if (includeMetric) {
+    private void optionallyAddMetric(boolean addMetric, String metricName) {
+        if (addMetric) {
             requestedMetrics.add(metricName);
-        } else {
-            requestedMetrics.remove(metricName);
         }
     }
 
@@ -261,16 +152,16 @@ public void writeTo(StreamOutput out) throws IOException {
         if (out.getVersion().before(Version.V_7_7_0)){
             // prior to version 8.x, a NodesInfoRequest was serialized as a list
             // of booleans in a fixed order
-            out.writeBoolean(Metrics.SETTINGS.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.OS.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.PROCESS.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.JVM.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.THREAD_POOL.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.TRANSPORT.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.HTTP.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.PLUGINS.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.INGEST.containedIn(requestedMetrics));
-            out.writeBoolean(Metrics.INDICES.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.SETTINGS.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.OS.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.PROCESS.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.JVM.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.THREAD_POOL.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.TRANSPORT.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.HTTP.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.PLUGINS.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.INGEST.containedIn(requestedMetrics));
+            out.writeBoolean(Metric.INDICES.containedIn(requestedMetrics));
         } else {
             out.writeStringArray(requestedMetrics.toArray(String[]::new));
         }
@@ -281,7 +172,7 @@ public void writeTo(StreamOutput out) throws IOException {
      * from the nodes information endpoint. Eventually this list list will be
      * pluggable.
      */
-    enum Metrics {
+    public enum Metric {
         SETTINGS("settings"),
         OS("os"),
         PROCESS("process"),
@@ -295,20 +186,20 @@ enum Metrics {
 
         private String metricName;
 
-        Metrics(String name) {
+        Metric(String name) {
             this.metricName = name;
         }
 
-        String metricName() {
+        public String metricName() {
             return this.metricName;
         }
 
         boolean containedIn(Set<String> metricNames) {
             return metricNames.contains(this.metricName());
         }
 
-        static Set<String> allMetrics() {
-            return Arrays.stream(values()).map(Metrics::metricName).collect(Collectors.toSet());
+        public static Set<String> allMetrics() {
+            return Arrays.stream(values()).map(Metric::metricName).collect(Collectors.toSet());
         }
     }
 }