deprecation info API: negative index.unassigned.node_left.delayed_timeout (#36454)

This commit adds support to check for negative values for index setting
`index.unassigned.node_left.delayed_timeout` for the deprecation info API.

relates #36024
relates #26828

Author: jakelandis

x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/DeprecationChecks.java

@@ -52,7 +52,8 @@ private DeprecationChecks() {
             IndexDeprecationChecks::oldIndicesCheck,
             IndexDeprecationChecks::delimitedPayloadFilterCheck,
             IndexDeprecationChecks::percolatorUnmappedFieldsAsStringCheck,
-            IndexDeprecationChecks::indexNameCheck
+            IndexDeprecationChecks::indexNameCheck,
+            IndexDeprecationChecks::nodeLeftDelayedTimeCheck
             ));
 
     /**

x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/IndexDeprecationChecks.java

@@ -11,7 +11,10 @@
 import org.elasticsearch.Version;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.cluster.metadata.MappingMetaData;
+import org.elasticsearch.cluster.routing.UnassignedInfo;
+import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.index.analysis.AnalysisRegistry;
 import org.elasticsearch.xpack.core.deprecation.DeprecationIssue;
 
@@ -128,5 +131,22 @@ static DeprecationIssue percolatorUnmappedFieldsAsStringCheck(IndexMetaData inde
                     "] been removed in favor of [index.percolator.map_unmapped_fields_as_text].");
         }
         return null;
+    }
+	
+	 static DeprecationIssue nodeLeftDelayedTimeCheck(IndexMetaData indexMetaData) {
+        String setting = UnassignedInfo.INDEX_DELAYED_NODE_LEFT_TIMEOUT_SETTING.getKey();
+        String value = indexMetaData.getSettings().get(setting);
+        if (Strings.isNullOrEmpty(value) == false) {
+            TimeValue parsedValue = TimeValue.parseTimeValue(value, setting);
+            if (parsedValue.getNanos() < 0) {
+                return new DeprecationIssue(DeprecationIssue.Level.WARNING,
+                    "Negative values for " + setting + " are deprecated and should be set to 0",
+                    "https://www.elastic.co/guide/en/elasticsearch/reference/master/breaking-changes-7.0.html" +
+                        "#_literal_index_unassigned_node_left_delayed_timeout_literal_may_no_longer_be_negative",
+                    "The index [" + indexMetaData.getIndex().getName() + "] has [" + setting + "] set to [" + value +
+                        "], but negative values are not allowed");
+            }
+        }
+        return null;
     }
 }

x-pack/plugin/deprecation/src/test/java/org/elasticsearch/xpack/deprecation/IndexDeprecationChecksTests.java

@@ -7,6 +7,7 @@
 
 import org.elasticsearch.Version;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
+import org.elasticsearch.cluster.routing.UnassignedInfo;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.test.VersionUtils;
@@ -106,4 +107,33 @@ public void testPercolatorUnmappedFieldsAsStringCheck() {
         List<DeprecationIssue> noIssues = DeprecationChecks.filterChecks(INDEX_SETTINGS_CHECKS, c -> c.apply(goodIndex));
         assertTrue(noIssues.isEmpty());
     }
+	
+	public void testNodeLeftDelayedTimeCheck() {
+        String negativeTimeValue = "-" + randomPositiveTimeValue();
+        String indexName = randomAlphaOfLengthBetween(0, 10);
+        String setting = UnassignedInfo.INDEX_DELAYED_NODE_LEFT_TIMEOUT_SETTING.getKey();
+
+        final IndexMetaData badIndex = IndexMetaData.builder(indexName)
+            .settings(settings(Version.CURRENT).put(setting, negativeTimeValue))
+            .numberOfShards(randomIntBetween(1, 100))
+            .numberOfReplicas(randomIntBetween(1, 15))
+            .build();
+        DeprecationIssue expected = new DeprecationIssue(DeprecationIssue.Level.WARNING,
+            "Negative values for " + setting + " are deprecated and should be set to 0",
+            "https://www.elastic.co/guide/en/elasticsearch/reference/master/breaking-changes-7.0.html" +
+                "#_literal_index_unassigned_node_left_delayed_timeout_literal_may_no_longer_be_negative",
+            "The index [" + indexName + "] has [" + setting + "] set to [" + negativeTimeValue +
+                "], but negative values are not allowed");
+
+        List<DeprecationIssue> issues = DeprecationChecks.filterChecks(INDEX_SETTINGS_CHECKS, c -> c.apply(badIndex));
+        assertEquals(singletonList(expected), issues);
+
+        final IndexMetaData goodIndex = IndexMetaData.builder(indexName)
+            .settings(settings(Version.CURRENT))
+            .numberOfShards(randomIntBetween(1, 100))
+            .numberOfReplicas(randomIntBetween(1, 15))
+            .build();
+        List<DeprecationIssue> noIssues = DeprecationChecks.filterChecks(INDEX_SETTINGS_CHECKS, c -> c.apply(goodIndex));
+        assertTrue(noIssues.isEmpty());
+    }
 }