Remove the suggest metric from stats APIs

docs/CHANGELOG.asciidoc

@@ -12,6 +12,8 @@
 <<write-thread-pool-fallback, Removed `thread_pool.bulk.*` settings and
 `es.thread_pool.write.use_bulk_as_display_name` system property>> ({pull}29609[#29609])
 
+<<remove-suggest-metric, Removed `suggest` metric on stats APIs>> ({pull}29635[#29635])
+
 === Breaking Java Changes
 
 === Deprecations

docs/reference/migration/migrate_7_0/api.asciidoc

@@ -22,7 +22,14 @@ The following parameters starting with underscore have been removed:
 Instead of these removed parameters, use their non camel case equivalents without
 starting underscore, e.g. use `version_type` instead of `_version_type` or `versionType`.
 
-
 ==== The parameter `fields` deprecated in 6.x has been removed from Bulk request 
 and Update request. The Update API returns `400 - Bad request` if request contains 
 unknown parameters (instead of ignored in the previous version).
+
+[[remove-suggest-metric]]
+==== Remove support for `suggest` metric/index metric in indices stats and nodes stats APIs
+
+Previously, `suggest` stats were folded into `search` stats. Support for the
+`suggest` metric on the indices stats and nodes stats APIs remained for
+backwards compatibility. Backwards support for the `suggest` metric was
+deprecated in 6.3.0 and now removed in 7.0.0.

server/src/main/java/org/elasticsearch/action/admin/indices/stats/CommonStats.java

@@ -152,9 +152,6 @@ public CommonStats(CommonStatsFlags flags) {
                 case Translog:
                     translog = new TranslogStats();
                     break;
-                case Suggest:
-                    // skip
-                    break;
                 case RequestCache:
                     requestCache = new RequestCacheStats();
                     break;
@@ -213,9 +210,6 @@ public CommonStats(IndicesQueryCache indicesQueryCache, IndexShard indexShard, C
                 case Translog:
                     translog = indexShard.translogStats();
                     break;
-                case Suggest:
-                    // skip
-                    break;
                 case RequestCache:
                     requestCache = indexShard.requestCache().stats();
                     break;

server/src/main/java/org/elasticsearch/action/admin/indices/stats/CommonStatsFlags.java

@@ -221,7 +221,7 @@ public enum Flag {
         Completion("completion", 11),
         Segments("segments", 12),
         Translog("translog", 13),
-        Suggest("suggest", 14), // unused
+        // 14 was previously used for Suggest
         RequestCache("request_cache", 15),
         Recovery("recovery", 16);
 

server/src/main/java/org/elasticsearch/action/admin/indices/stats/IndicesStatsRequest.java

@@ -229,15 +229,6 @@ public boolean translog() {
         return flags.isSet(Flag.Translog);
     }
 
-    public IndicesStatsRequest suggest(boolean suggest) {
-        flags.set(Flag.Suggest, suggest);
-        return this;
-    }
-
-    public boolean suggest() {
-        return flags.isSet(Flag.Suggest);
-    }
-
     public IndicesStatsRequest requestCache(boolean requestCache) {
         flags.set(Flag.RequestCache, requestCache);
         return this;

server/src/main/java/org/elasticsearch/action/admin/indices/stats/TransportIndicesStatsAction.java

@@ -148,9 +148,6 @@ protected ShardStats shardOperation(IndicesStatsRequest request, ShardRouting sh
         if (request.translog()) {
             flags.set(CommonStatsFlags.Flag.Translog);
         }
-        if (request.suggest()) {
-            flags.set(CommonStatsFlags.Flag.Suggest);
-        }
         if (request.requestCache()) {
             flags.set(CommonStatsFlags.Flag.RequestCache);
         }

server/src/main/java/org/elasticsearch/rest/action/admin/cluster/RestNodesStatsAction.java

@@ -146,10 +146,6 @@ public RestChannelConsumer prepareRequest(final RestRequest request, final NodeC
                     for (final String indexMetric : indexMetrics) {
                         final Consumer<CommonStatsFlags> handler = FLAGS.get(indexMetric);
                         if (handler != null) {
-                            if ("suggest".equals(indexMetric)) {
-                                deprecationLogger.deprecated(
-                                        "the suggest index metric is deprecated on the nodes stats API [" + request.uri() + "]");
-                            }
                             handler.accept(flags);
                         } else {
                             invalidIndexMetrics.add(indexMetric);

server/src/main/java/org/elasticsearch/rest/action/admin/indices/RestIndicesStatsAction.java

@@ -62,7 +62,6 @@ public String getName() {
         metrics.put("store", r -> r.store(true));
         metrics.put("indexing", r -> r.indexing(true));
         metrics.put("search", r -> r.search(true));
-        metrics.put("suggest", r -> r.search(true));
         metrics.put("get", r -> r.get(true));
         metrics.put("merge", r -> r.merge(true));
         metrics.put("refresh", r -> r.refresh(true));
@@ -102,9 +101,6 @@ public RestChannelConsumer prepareRequest(final RestRequest request, final NodeC
             for (final String metric : metrics) {
                 final Consumer<IndicesStatsRequest> consumer = METRICS.get(metric);
                 if (consumer != null) {
-                    if ("suggest".equals(metric)) {
-                        deprecationLogger.deprecated("the suggest metric is deprecated on the indices stats API [" + request.uri() + "]");
-                    }
                     consumer.accept(indicesStatsRequest);
                 } else {
                     invalidMetrics.add(metric);

server/src/test/java/org/elasticsearch/indices/stats/IndexStatsIT.java

@@ -589,10 +589,6 @@ public void testAllFlags() throws Exception {
 
         IndicesStatsResponse stats = builder.execute().actionGet();
         for (Flag flag : values) {
-            if (flag == Flag.Suggest) {
-                // suggest flag is unused
-                continue;
-            }
             assertThat(isSet(flag, stats.getPrimaries()), equalTo(false));
             assertThat(isSet(flag, stats.getTotal()), equalTo(false));
         }
@@ -628,10 +624,6 @@ public void testAllFlags() throws Exception {
         }
 
         for (Flag flag : EnumSet.complementOf(flags)) { // check the complement
-            if (flag == Flag.Suggest) {
-                // suggest flag is unused
-                continue;
-            }
             assertThat(isSet(flag, stats.getPrimaries()), equalTo(false));
             assertThat(isSet(flag, stats.getTotal()), equalTo(false));
         }
@@ -684,7 +676,7 @@ public void testEncodeDecodeCommonStats() throws IOException {
     public void testFlagOrdinalOrder() {
         Flag[] flags = new Flag[]{Flag.Store, Flag.Indexing, Flag.Get, Flag.Search, Flag.Merge, Flag.Flush, Flag.Refresh,
                 Flag.QueryCache, Flag.FieldData, Flag.Docs, Flag.Warmer, Flag.Completion, Flag.Segments,
-                Flag.Translog, Flag.Suggest, Flag.RequestCache, Flag.Recovery};
+                Flag.Translog, Flag.RequestCache, Flag.Recovery};
 
         assertThat(flags.length, equalTo(Flag.values().length));
         for (int i = 0; i < flags.length; i++) {
@@ -935,8 +927,6 @@ private static void set(Flag flag, IndicesStatsRequestBuilder builder, boolean s
             case Translog:
                 builder.setTranslog(set);
                 break;
-            case Suggest: // unused
-                break;
             case RequestCache:
                 builder.setRequestCache(set);
                 break;
@@ -979,8 +969,6 @@ private static boolean isSet(Flag flag, CommonStats response) {
                 return response.getSegments() != null;
             case Translog:
                 return response.getTranslog() != null;
-            case Suggest: // unused
-                return true;
             case RequestCache:
                 return response.getRequestCache() != null;
             case Recovery:

server/src/test/java/org/elasticsearch/rest/action/admin/cluster/RestNodesStatsActionTests.java

@@ -148,14 +148,4 @@ public void testIndexMetricsRequestOnAllRequest() throws IOException {
                 containsString("request [/_nodes/stats] contains index metrics [" + indexMetric + "] but all stats requested")));
     }
 
-    public void testSuggestIsDeprecated() throws IOException {
-        final Map<String, String> params =
-                Stream.of(Tuple.tuple("metric", "indices"), Tuple.tuple("index_metric", "suggest"))
-                        .collect(Collectors.toMap(Tuple::v1, Tuple::v2));
-        final RestRequest request =
-                new FakeRestRequest.Builder(xContentRegistry()).withPath("/_nodes/stats").withParams(params).build();
-        action.prepareRequest(request, mock(NodeClient.class));
-        assertWarnings("the suggest index metric is deprecated on the nodes stats API [/_nodes/stats]" );
-    }
-
 }

server/src/test/java/org/elasticsearch/rest/action/admin/indices/RestIndicesStatsActionTests.java

@@ -84,11 +84,4 @@ public void testAllRequestWithOtherMetrics() throws IOException {
         assertThat(e, hasToString(containsString("request [/_stats] contains _all and individual metrics [_all," + metric + "]")));
     }
 
-    public void testSuggestIsDeprecated() throws IOException {
-        final Map<String, String> params = Collections.singletonMap("metric", "suggest");
-        final RestRequest request = new FakeRestRequest.Builder(xContentRegistry()).withPath("/_stats").withParams(params).build();
-        action.prepareRequest(request, mock(NodeClient.class));
-        assertWarnings("the suggest metric is deprecated on the indices stats API [/_stats]");
-    }
-
 }