Forbid index names over 100 characters in length

Fixes #4417

Author: dakrone

src/main/java/org/elasticsearch/cluster/metadata/MetaDataCreateIndexService.java

@@ -36,8 +36,7 @@
 import org.elasticsearch.cluster.ack.ClusterStateUpdateResponse;
 import org.elasticsearch.cluster.block.ClusterBlock;
 import org.elasticsearch.cluster.block.ClusterBlocks;
-import org.elasticsearch.cluster.metadata.IndexMetaData.Custom;
-import org.elasticsearch.cluster.metadata.IndexMetaData.State;
+import org.elasticsearch.cluster.metadata.IndexMetaData.*;
 import org.elasticsearch.cluster.node.DiscoveryNodes;
 import org.elasticsearch.cluster.routing.RoutingTable;
 import org.elasticsearch.cluster.routing.allocation.AllocationService;
@@ -72,6 +71,7 @@
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.InputStreamReader;
+import java.io.UnsupportedEncodingException;
 import java.util.Comparator;
 import java.util.List;
 import java.util.Locale;
@@ -87,6 +87,8 @@
  */
 public class MetaDataCreateIndexService extends AbstractComponent {
 
+    public final static int MAX_INDEX_NAME_BYTES = 100;
+
     private final Environment environment;
     private final ThreadPool threadPool;
     private final ClusterService clusterService;
@@ -172,6 +174,18 @@ public void validateIndexName(String index, ClusterState state) throws Elasticse
         if (!index.toLowerCase(Locale.ROOT).equals(index)) {
             throw new InvalidIndexNameException(new Index(index), index, "must be lowercase");
         }
+        int byteCount = 0;
+        try {
+            byteCount = index.getBytes("UTF-8").length;
+        } catch (UnsupportedEncodingException e) {
+            // UTF-8 should always be supported, but rethrow this if it is not for some reason
+            throw new ElasticsearchException("Unable to determine length of index name", e);
+        }
+        if (byteCount > MAX_INDEX_NAME_BYTES) {
+            throw new InvalidIndexNameException(new Index(index), index,
+                    "index name is too long, (" + byteCount +
+                    " > " + MAX_INDEX_NAME_BYTES + ")");
+        }
         if (state.metaData().aliases().containsKey(index)) {
             throw new InvalidIndexNameException(new Index(index), index, "already exists as alias");
         }

src/test/java/org/elasticsearch/indexing/IndexActionTests.java

@@ -21,13 +21,16 @@
 import org.elasticsearch.action.bulk.BulkResponse;
 import org.elasticsearch.action.index.IndexRequestBuilder;
 import org.elasticsearch.action.index.IndexResponse;
+import org.elasticsearch.cluster.metadata.MetaDataCreateIndexService;
 import org.elasticsearch.index.VersionType;
+import org.elasticsearch.indices.InvalidIndexNameException;
 import org.elasticsearch.test.ElasticsearchIntegrationTest;
 import org.elasticsearch.test.junit.annotations.TestLogging;
 import org.junit.Test;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Locale;
 import java.util.Random;
 import java.util.concurrent.Callable;
 import java.util.concurrent.ExecutorService;
@@ -177,4 +180,39 @@ public void testCreateFlagWithBulk() {
         IndexResponse indexResponse = bulkResponse.getItems()[0].getResponse();
         assertTrue(indexResponse.isCreated());
     }
+
+    @Test
+    public void testCreateIndexWithLongName() {
+        int min = MetaDataCreateIndexService.MAX_INDEX_NAME_BYTES + 1;
+        int max = MetaDataCreateIndexService.MAX_INDEX_NAME_BYTES * 2;
+        try {
+            createIndex(randomAsciiOfLengthBetween(min, max).toLowerCase(Locale.ROOT));
+            fail("exception should have been thrown on too-long index name");
+        } catch (InvalidIndexNameException e) {
+            assertThat("exception contains message about index name too long: " + e.getMessage(),
+                    e.getMessage().contains("index name is too long,"), equalTo(true));
+        }
+
+        try {
+            client().prepareIndex(randomAsciiOfLengthBetween(min, max).toLowerCase(Locale.ROOT), "mytype").setSource("foo", "bar").get();
+            fail("exception should have been thrown on too-long index name");
+        } catch (InvalidIndexNameException e) {
+            assertThat("exception contains message about index name too long: " + e.getMessage(),
+                    e.getMessage().contains("index name is too long,"), equalTo(true));
+        }
+
+        try {
+            // Catch chars that are more than a single byte
+            client().prepareIndex(randomAsciiOfLength(MetaDataCreateIndexService.MAX_INDEX_NAME_BYTES -1).toLowerCase(Locale.ROOT) +
+                            "Ϟ".toLowerCase(Locale.ROOT),
+                    "mytype").setSource("foo", "bar").get();
+            fail("exception should have been thrown on too-long index name");
+        } catch (InvalidIndexNameException e) {
+            assertThat("exception contains message about index name too long: " + e.getMessage(),
+                    e.getMessage().contains("index name is too long,"), equalTo(true));
+        }
+
+        // we can create an index of max length
+        createIndex(randomAsciiOfLength(MetaDataCreateIndexService.MAX_INDEX_NAME_BYTES).toLowerCase(Locale.ROOT));
+    }
 }