SOLR-18175: Return BAD_REQUEST for FieldExistsQuery IllegalStateException

solr/core/src/java/org/apache/solr/handler/component/QueryComponent.java

@@ -133,6 +133,7 @@
  */
 public class QueryComponent extends SearchComponent {
   public static final String COMPONENT_NAME = "query";
+  private static final String FIELD_EXISTS_QUERY_REQUIRES_PREFIX = "FieldExistsQuery requires";
   private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
 
   @Override
@@ -435,6 +436,9 @@ public void process(ResponseBuilder rb) throws IOException {
         }
       } catch (SyntaxError e) {
         throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, e);
+      } catch (IllegalStateException e) {
+        maybeThrowBadRequestForFieldExistsQueryFailure(e);
+        throw e;
       }
       return;
     }
@@ -1835,6 +1839,9 @@ private void doProcessUngroupedSearch(ResponseBuilder rb, QueryCommand cmd) thro
       result = searcher.search(cmd);
     } catch (FuzzyTermsEnum.FuzzyTermsException e) {
       throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, e);
+    } catch (IllegalStateException e) {
+      maybeThrowBadRequestForFieldExistsQueryFailure(e);
+      throw e;
     }
     rb.setResult(result);
 
@@ -1885,4 +1892,14 @@ private static String generateQueryID(SolrQueryRequest req) {
 
     return localQueryID;
   }
+
+  private static void maybeThrowBadRequestForFieldExistsQueryFailure(IllegalStateException e) {
+    for (Throwable cause = e; cause != null; cause = cause.getCause()) {
+      if (cause instanceof IllegalStateException
+          && cause.getMessage() != null
+          && cause.getMessage().startsWith(FIELD_EXISTS_QUERY_REQUIRES_PREFIX)) {
+        throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, cause.getMessage(), e);
+      }
+    }
+  }
 }

solr/core/src/test/org/apache/solr/handler/component/QueryComponentFieldExistsQueryErrorHandlingTest.java

@@ -0,0 +1,106 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.solr.handler.component;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import org.apache.solr.SolrTestCaseJ4;
+import org.apache.solr.common.SolrException;
+import org.apache.solr.request.SolrQueryRequest;
+import org.apache.solr.response.SolrQueryResponse;
+import org.apache.solr.search.QueryCommand;
+import org.apache.solr.search.SolrIndexSearcher;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+public class QueryComponentFieldExistsQueryErrorHandlingTest extends SolrTestCaseJ4 {
+
+  @BeforeClass
+  public static void beforeClass() {
+    assumeWorkingMockito();
+  }
+
+  @Test
+  public void mapsFieldExistsQueryIllegalStateExceptionToBadRequest() throws Exception {
+    SolrIndexSearcher searcher = Mockito.mock(SolrIndexSearcher.class);
+    IllegalStateException fieldExistsError =
+        new IllegalStateException("FieldExistsQuery requires norms, docValues, or vectors");
+    Mockito.when(searcher.search(Mockito.any(QueryCommand.class))).thenThrow(fieldExistsError);
+
+    InvocationTargetException thrown =
+        expectThrows(
+            InvocationTargetException.class,
+            () -> invokeDoProcessUngroupedSearch(newResponseBuilder(searcher), new QueryCommand()));
+
+    assertTrue(thrown.getCause() instanceof SolrException);
+    SolrException solrException = (SolrException) thrown.getCause();
+    assertEquals(SolrException.ErrorCode.BAD_REQUEST.code, solrException.code());
+    assertTrue(solrException.getMessage().startsWith("FieldExistsQuery requires"));
+  }
+
+  @Test
+  public void mapsNestedFieldExistsQueryIllegalStateExceptionToBadRequest() throws Exception {
+    SolrIndexSearcher searcher = Mockito.mock(SolrIndexSearcher.class);
+    IllegalStateException rootCause =
+        new IllegalStateException("FieldExistsQuery requires norms, docValues, or vectors");
+    IllegalStateException wrapped = new IllegalStateException("outer", rootCause);
+    Mockito.when(searcher.search(Mockito.any(QueryCommand.class))).thenThrow(wrapped);
+
+    InvocationTargetException thrown =
+        expectThrows(
+            InvocationTargetException.class,
+            () -> invokeDoProcessUngroupedSearch(newResponseBuilder(searcher), new QueryCommand()));
+
+    assertTrue(thrown.getCause() instanceof SolrException);
+    SolrException solrException = (SolrException) thrown.getCause();
+    assertEquals(SolrException.ErrorCode.BAD_REQUEST.code, solrException.code());
+    assertTrue(solrException.getMessage().startsWith("FieldExistsQuery requires"));
+  }
+
+  @Test
+  public void leavesOtherIllegalStateExceptionsUnchanged() throws Exception {
+    SolrIndexSearcher searcher = Mockito.mock(SolrIndexSearcher.class);
+    IllegalStateException nonFieldExistsError =
+        new IllegalStateException("not a field exists query");
+    Mockito.when(searcher.search(Mockito.any(QueryCommand.class))).thenThrow(nonFieldExistsError);
+
+    InvocationTargetException thrown =
+        expectThrows(
+            InvocationTargetException.class,
+            () -> invokeDoProcessUngroupedSearch(newResponseBuilder(searcher), new QueryCommand()));
+
+    assertSame(nonFieldExistsError, thrown.getCause());
+  }
+
+  private static void invokeDoProcessUngroupedSearch(ResponseBuilder rb, QueryCommand cmd)
+      throws Exception {
+    Method method =
+        QueryComponent.class.getDeclaredMethod(
+            "doProcessUngroupedSearch", ResponseBuilder.class, QueryCommand.class);
+    method.setAccessible(true);
+    method.invoke(new QueryComponent(), rb, cmd);
+  }
+
+  private static ResponseBuilder newResponseBuilder(SolrIndexSearcher searcher) {
+    SolrQueryRequest req = Mockito.mock(SolrQueryRequest.class);
+    SolrQueryResponse rsp = Mockito.mock(SolrQueryResponse.class);
+    Mockito.when(req.getSearcher()).thenReturn(searcher);
+    return new ResponseBuilder(req, rsp, new ArrayList<>(0));
+  }
+}