ES|QL Make index resolution required

x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/EsqlRestValidationTestCase.java

@@ -73,21 +73,23 @@ public void wipeTestData() throws IOException {
         }
     }
 
-    private String getInexistentIndexErrorMessage() {
-        return "\"reason\" : \"Found 1 problem\\nline 1:1: Unknown index ";
-    }
-
     public void testInexistentIndexNameWithWildcard() throws IOException {
-        assertErrorMessages(inexistentIndexNameWithWildcard, getInexistentIndexErrorMessage(), 400);
+        for (String indexName : inexistentIndexNameWithWildcard) {
+            assertErrorMessage(indexName, "Unknown index " + "[" + clusterSpecificIndexName(indexName) + "]", 400);
+        }
     }
 
+    @AwaitsFix(bugUrl = "TBD")
+    // field caps report only first missing index
     public void testInexistentIndexNameWithoutWildcard() throws IOException {
-        assertErrorMessages(inexistentIndexNameWithoutWildcard, getInexistentIndexErrorMessage(), 400);
+        for (String indexName : inexistentIndexNameWithoutWildcard) {
+            assertErrorMessage(indexName, "Unknown index " + "[" + clusterSpecificIndexName(indexName) + "]", 400);
+        }
     }
 
     public void testExistentIndexWithoutWildcard() throws IOException {
         for (String indexName : existentIndexWithoutWildcard) {
-            assertErrorMessage(indexName, "\"reason\" : \"no such index [inexistent]\"", 404);
+            assertErrorMessage(indexName, "Unknown index [inexistent]", 400);
         }
     }
 
@@ -99,19 +101,13 @@ public void testAlias() throws IOException {
         createAlias();
 
         for (String indexName : existentAliasWithoutWildcard) {
-            assertErrorMessage(indexName, "\"reason\" : \"no such index [inexistent]\"", 404);
+            assertErrorMessage(indexName, "Unknown index [inexistent]", 400);
         }
         assertValidRequestOnIndices(existentAliasWithWildcard);
 
         deleteAlias();
     }
 
-    private void assertErrorMessages(String[] indices, String errorMessage, int statusCode) throws IOException {
-        for (String indexName : indices) {
-            assertErrorMessage(indexName, errorMessage + "[" + clusterSpecificIndexName(indexName) + "]", statusCode);
-        }
-    }
-
     protected String clusterSpecificIndexName(String indexName) {
         return indexName;
     }

x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/RequestIndexFilteringTestCase.java

@@ -212,9 +212,9 @@ public void testIndicesDontExist() throws IOException {
         assertThat(e.getMessage(), anyOf(containsString("Unknown index [foo*]"), containsString("Unknown index [remote_cluster:foo*]")));
 
         e = expectThrows(ResponseException.class, () -> runEsql(timestampFilter("gte", "2020-01-01").query("FROM foo, test1")));
-        assertEquals(404, e.getResponse().getStatusLine().getStatusCode());
-        assertThat(e.getMessage(), containsString("index_not_found_exception"));
-        assertThat(e.getMessage(), containsString("no such index [foo]"));
+        assertEquals(400, e.getResponse().getStatusLine().getStatusCode());
+        assertThat(e.getMessage(), containsString("verification_exception"));
+        assertThat(e.getMessage(), containsString("Unknown index [foo]"));
 
         // Don't test remote patterns here, we'll test them in the multi-cluster tests
         if (EsqlCapabilities.Cap.JOIN_LOOKUP_V12.isEnabled()) {

x-pack/plugin/esql/src/internalClusterTest/java/org/elasticsearch/xpack/esql/plugin/IndexResolutionIT.java

@@ -17,7 +17,6 @@
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.util.CollectionUtils;
 import org.elasticsearch.datastreams.DataStreamsPlugin;
-import org.elasticsearch.index.IndexNotFoundException;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.xpack.esql.VerificationException;
 import org.elasticsearch.xpack.esql.action.AbstractEsqlIntegTestCase;
@@ -200,22 +199,18 @@ public void testUnavailableIndex() {
     }
 
     public void testPartialResolution() {
-        assertAcked(client().admin().indices().prepareCreate("index-1"));
-        assertAcked(client().admin().indices().prepareCreate("index-2"));
-        indexRandom(true, "index-2", 10);
+        assertAcked(client().admin().indices().prepareCreate("data"));
+        indexRandom(true, "data", 10);
 
-        try (var response = run(syncEsqlQueryRequest().query("FROM index-1,nonexisting-1"))) {
-            assertOk(response); // okay when present index is empty
-        }
         expectThrows(
-            IndexNotFoundException.class,
-            equalTo("no such index [nonexisting-1]"), // fails when present index is non-empty
-            () -> run(syncEsqlQueryRequest().query("FROM index-2,nonexisting-1"))
+            VerificationException.class,
+            containsString("Unknown index [nonexisting-1]"),
+            () -> run(syncEsqlQueryRequest().query("FROM data,nonexisting-1"))
         );
         expectThrows(
-            IndexNotFoundException.class,
-            equalTo("no such index [nonexisting-1]"), // only the first missing index is reported
-            () -> run(syncEsqlQueryRequest().query("FROM index-2,nonexisting-1,nonexisting-2"))
+            VerificationException.class,
+            containsString("Unknown index [nonexisting-1]"), // only the first missing index is reported
+            () -> run(syncEsqlQueryRequest().query("FROM data,nonexisting-1,nonexisting-2"))
         );
     }
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/session/IndexResolver.java

@@ -6,6 +6,7 @@
  */
 package org.elasticsearch.xpack.esql.session;
 
+import org.elasticsearch.ElasticsearchSecurityException;
 import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.fieldcaps.FieldCapabilitiesIndexResponse;
 import org.elasticsearch.action.fieldcaps.FieldCapabilitiesRequest;
@@ -16,6 +17,7 @@
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.util.Maps;
 import org.elasticsearch.index.IndexMode;
+import org.elasticsearch.index.IndexNotFoundException;
 import org.elasticsearch.index.mapper.TimeSeriesParams;
 import org.elasticsearch.index.query.QueryBuilder;
 import org.elasticsearch.threadpool.ThreadPool;
@@ -56,7 +58,7 @@ public class IndexResolver {
     public static final String UNMAPPED = "unmapped";
 
     public static final IndicesOptions FIELD_CAPS_INDICES_OPTIONS = IndicesOptions.builder()
-        .concreteTargetOptions(IndicesOptions.ConcreteTargetOptions.ALLOW_UNAVAILABLE_TARGETS)
+        .concreteTargetOptions(IndicesOptions.ConcreteTargetOptions.ERROR_WHEN_UNAVAILABLE_TARGETS)
         .wildcardOptions(
             IndicesOptions.WildcardOptions.builder()
                 .matchOpen(true)
@@ -91,10 +93,19 @@ public void resolveAsMergedMapping(
         client.execute(
             EsqlResolveFieldsAction.TYPE,
             createFieldCapsRequest(indexWildcard, fieldNames, requestFilter, includeAllDimensions),
-            listener.delegateFailureAndWrap(
-                (l, response) -> l.onResponse(
-                    mergedMappings(indexWildcard, new FieldsInfo(response, supportsAggregateMetricDouble, supportsDenseVector))
-                )
+            ActionListener.wrap(
+                r -> listener.onResponse(
+                    mergedMappings(indexWildcard, new FieldsInfo(r, supportsAggregateMetricDouble, supportsDenseVector))
+                ),
+                f -> {
+                    if (f instanceof IndexNotFoundException e) {
+                        listener.onResponse(IndexResolution.notFound(e.getIndex().getName()));
+                    } else if (f instanceof ElasticsearchSecurityException e) {
+                        listener.onResponse(IndexResolution.notFound(indexWildcard));
+                    } else {
+                        listener.onFailure(f);
+                    }
+                }
             )
         );
     }