"did you mean" for ObjectParser with top named (#51018)

When you declare an ObjectParser with top level named objects like we do
with `significant_terms` we didn't support "did you mean". This fixes
that.

Relates #50938

Author: nik9000

libs/x-content/src/main/java/org/elasticsearch/common/xcontent/NamedObjectNotFoundException.java

@@ -24,12 +24,17 @@
  * parse for a particular name
  */
 public class NamedObjectNotFoundException extends XContentParseException {
+    private final Iterable<String> candidates;
 
-    public NamedObjectNotFoundException(String message) {
-        this(null, message);
+    public NamedObjectNotFoundException(XContentLocation location, String message, Iterable<String> candidates) {
+        super(location, message);
+        this.candidates = candidates;
     }
 
-    public NamedObjectNotFoundException(XContentLocation location, String message) {
-        super(location, message);
+    /**
+     * The possible matches.
+     */
+    public Iterable<String> getCandidates() {
+        return candidates;
     }
 }

libs/x-content/src/main/java/org/elasticsearch/common/xcontent/NamedXContentRegistry.java

@@ -123,19 +123,18 @@ public <T, C> T parseNamedObject(Class<T> categoryClass, String name, XContentPa
         if (parsers == null) {
             if (registry.isEmpty()) {
                 // The "empty" registry will never work so we throw a better exception as a hint.
-                throw new NamedObjectNotFoundException("named objects are not supported for this parser");
+                throw new XContentParseException("named objects are not supported for this parser");
             }
-            throw new NamedObjectNotFoundException("unknown named object category [" + categoryClass.getName() + "]");
+            throw new XContentParseException("unknown named object category [" + categoryClass.getName() + "]");
         }
         Entry entry = parsers.get(name);
         if (entry == null) {
-            throw new NamedObjectNotFoundException(parser.getTokenLocation(), "unable to parse " + categoryClass.getSimpleName() +
-                " with name [" + name + "]: parser not found");
+            throw new NamedObjectNotFoundException(parser.getTokenLocation(), "unknown field [" + name + "]", parsers.keySet());
         }
         if (false == entry.name.match(name, parser.getDeprecationHandler())) {
             /* Note that this shouldn't happen because we already looked up the entry using the names but we need to call `match` anyway
              * because it is responsible for logging deprecation warnings. */
-            throw new NamedObjectNotFoundException(parser.getTokenLocation(),
+            throw new XContentParseException(parser.getTokenLocation(),
                     "unable to parse " + categoryClass.getSimpleName() + " with name [" + name + "]: parser didn't match");
         }
         return categoryClass.cast(entry.parser.parse(parser, context));

libs/x-content/src/main/java/org/elasticsearch/common/xcontent/ObjectParser.java

@@ -27,8 +27,10 @@
 import java.util.Arrays;
 import java.util.EnumSet;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.function.BiConsumer;
 import java.util.function.BiFunction;
 import java.util.function.Consumer;
@@ -140,8 +142,10 @@ private static <Value, Category, Context> UnknownFieldParser<Value, Context> unk
             try {
                 o = parser.namedObject(categoryClass, field, context);
             } catch (NamedObjectNotFoundException e) {
-                // TODO It'd be lovely if we could the options here but we don't have the right stuff plumbed through. We'll get to it!
-                throw new XContentParseException(location, "[" + objectParser.name  + "] " + e.getBareMessage(), e);
+                Set<String> candidates = new HashSet<>(objectParser.fieldParserMap.keySet());
+                e.getCandidates().forEach(candidates::add);
+                String message = ErrorOnUnknown.IMPLEMENTATION.errorMessage(objectParser.name, field, candidates);
+                throw new XContentParseException(location, message, e);
             }
             consumer.accept(value, o);
         };

libs/x-content/src/main/java/org/elasticsearch/common/xcontent/XContentParseException.java

@@ -59,13 +59,6 @@ public XContentLocation getLocation() {
 
     @Override
     public String getMessage() {
-        return location.map(l -> "[" + l.toString() + "] ").orElse("") + getBareMessage();
-    }
-
-    /**
-     * Get the exception message without location information.
-     */
-    public String getBareMessage() {
-        return super.getMessage();
+        return location.map(l -> "[" + l.toString() + "] ").orElse("") + super.getMessage();
     }
 }

libs/x-content/src/test/java/org/elasticsearch/common/xcontent/ObjectParserTests.java

@@ -38,6 +38,7 @@
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicReference;
 
+import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.hasSize;
@@ -803,7 +804,9 @@ public void testTopLevelNamedXContent() throws IOException {
         {
             XContentParser parser = createParser(JsonXContent.jsonXContent, "{\"not_supported_field\" : \"foo\"}");
             XContentParseException ex = expectThrows(XContentParseException.class, () -> TopLevelNamedXConent.PARSER.parse(parser, null));
-            assertEquals("[1:2] [test] unable to parse Object with name [not_supported_field]: parser not found", ex.getMessage());
+            assertEquals("[1:2] [test] unknown field [not_supported_field]", ex.getMessage());
+            NamedObjectNotFoundException cause = (NamedObjectNotFoundException) ex.getCause();
+            assertThat(cause.getCandidates(), containsInAnyOrder("str", "int", "float", "bool"));
         }
     }
 

rest-api-spec/src/main/resources/rest-api-spec/test/search.aggregation/30_sig_terms.yml

@@ -137,3 +137,18 @@
       search:
         rest_total_hits_as_int: true
         body: { "size" : 0, "aggs" : { "ip_terms" : { "significant_terms" : { "field" : "ip", "exclude" :  "127.*"  } } } }
+
+---
+'Misspelled fields get "did you mean"':
+  - skip:
+      version: " - 7.99.99"
+      reason: Implemented in 8.0 (to be backported to 7.7)
+  - do:
+      catch: /\[significant_terms\] unknown field \[jlp\] did you mean \[jlh\]\?/
+      search:
+          body:
+            aggs:
+              foo:
+                significant_terms:
+                  field: foo
+                  jlp: {}

server/src/test/java/org/elasticsearch/common/xcontent/BaseXContentTestCase.java

@@ -22,6 +22,7 @@
 import com.fasterxml.jackson.core.JsonGenerationException;
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonParseException;
+
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.Constants;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
@@ -78,6 +79,7 @@
 import static java.util.Collections.emptyMap;
 import static java.util.Collections.singletonMap;
 import static org.hamcrest.Matchers.allOf;
+import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.endsWith;
 import static org.hamcrest.Matchers.equalTo;
@@ -1169,16 +1171,17 @@ public void testNamedObject() throws IOException {
             {
                 NamedObjectNotFoundException e = expectThrows(NamedObjectNotFoundException.class,
                     () -> p.namedObject(Object.class, "unknown", null));
-                assertThat(e.getMessage(), endsWith("unable to parse Object with name [unknown]: parser not found"));
+                assertThat(e.getMessage(), endsWith("unknown field [unknown]"));
+                assertThat(e.getCandidates(), containsInAnyOrder("test1", "test2", "deprecated", "str"));
             }
             {
-                Exception e = expectThrows(NamedObjectNotFoundException.class, () -> p.namedObject(String.class, "doesn't matter", null));
+                Exception e = expectThrows(XContentParseException.class, () -> p.namedObject(String.class, "doesn't matter", null));
                 assertEquals("unknown named object category [java.lang.String]", e.getMessage());
             }
         }
         try (XContentParser emptyRegistryParser = xcontentType().xContent()
             .createParser(NamedXContentRegistry.EMPTY, DeprecationHandler.THROW_UNSUPPORTED_OPERATION, new byte[] {})) {
-            Exception e = expectThrows(NamedObjectNotFoundException.class,
+            Exception e = expectThrows(XContentParseException.class,
                 () -> emptyRegistryParser.namedObject(String.class, "doesn't matter", null));
             assertEquals("named objects are not supported for this parser", e.getMessage());
         }

server/src/test/java/org/elasticsearch/common/xcontent/XContentParserUtilsTests.java

@@ -190,7 +190,7 @@ public void testParseTypedKeysObject() throws IOException {
             ensureExpectedToken(XContentParser.Token.START_OBJECT, parser.nextToken(), parser::getTokenLocation);
             NamedObjectNotFoundException e = expectThrows(NamedObjectNotFoundException.class,
                     () -> parseTypedKeysObject(parser, delimiter, Boolean.class, a -> {}));
-            assertThat(e.getMessage(), endsWith("unable to parse Boolean with name [type]: parser not found"));
+            assertThat(e.getMessage(), endsWith("unknown field [type]"));
         }
 
         final long longValue = randomLong();

server/src/test/java/org/elasticsearch/gateway/MetaDataStateFormatTests.java

@@ -30,9 +30,12 @@
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.ExceptionsHelper;
 import org.elasticsearch.Version;
+import org.elasticsearch.cluster.ClusterModule;
 import org.elasticsearch.cluster.metadata.IndexGraveyard;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.cluster.metadata.MetaData;
+import org.elasticsearch.cluster.metadata.RepositoriesMetaData;
+import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.UUIDs;
 import org.elasticsearch.common.collect.ImmutableOpenMap;
 import org.elasticsearch.common.xcontent.NamedXContentRegistry;
@@ -277,7 +280,7 @@ private void runLoadStateTest(boolean hasMissingCustoms, boolean preserveUnknown
         List<Path> dirList = Arrays.asList(dirs);
         Collections.shuffle(dirList, random());
         MetaData loadedMetaData = format.loadLatestState(logger, hasMissingCustoms ?
-            NamedXContentRegistry.EMPTY : xContentRegistry(), dirList.toArray(new Path[0]));
+            xContentRegistryWithMissingCustoms() : xContentRegistry(), dirList.toArray(new Path[0]));
         MetaData latestMetaData = meta.get(numStates-1);
         assertThat(loadedMetaData.clusterUUID(), not(equalTo("_na_")));
         assertThat(loadedMetaData.clusterUUID(), equalTo(latestMetaData.clusterUUID()));
@@ -706,4 +709,20 @@ public long addDummyFiles(String prefix, Path... paths) throws IOException {
         }
         return realId + 1;
     }
+
+    /**
+     * The {@link NamedXContentRegistry} to use for most {@link XContentParser} in this test.
+     */
+    protected final NamedXContentRegistry xContentRegistry() {
+        return new NamedXContentRegistry(ClusterModule.getNamedXWriteables());
+    }
+
+    /**
+     * The {@link NamedXContentRegistry} to use for {@link XContentParser}s that should be
+     * missing all of the normal cluster state parsers.
+     */
+    protected NamedXContentRegistry xContentRegistryWithMissingCustoms() {
+        return new NamedXContentRegistry(Arrays.asList(
+                new NamedXContentRegistry.Entry(MetaData.Custom.class, new ParseField("garbage"), RepositoriesMetaData::fromXContent)));
+    }
 }

server/src/test/java/org/elasticsearch/search/rescore/QueryRescorerBuilderTests.java

@@ -223,7 +223,7 @@ public void testUnknownFieldsExpection() throws IOException {
             "}\n";
         try (XContentParser parser = createParser(rescoreElement)) {
             Exception e = expectThrows(NamedObjectNotFoundException.class, () -> RescorerBuilder.parseFromXContent(parser));
-            assertEquals("[3:27] unable to parse RescorerBuilder with name [bad_rescorer_name]: parser not found", e.getMessage());
+            assertEquals("[3:27] unknown field [bad_rescorer_name]", e.getMessage());
         }
         rescoreElement = "{\n" +
             "    \"bad_fieldName\" : 20\n" +

server/src/test/java/org/elasticsearch/search/suggest/SuggestionTests.java

@@ -187,7 +187,7 @@ public void testUnknownSuggestionTypeThrows() throws IOException {
             ensureExpectedToken(XContentParser.Token.FIELD_NAME, parser.nextToken(), parser::getTokenLocation);
             ensureExpectedToken(XContentParser.Token.START_ARRAY, parser.nextToken(), parser::getTokenLocation);
             NamedObjectNotFoundException e = expectThrows(NamedObjectNotFoundException.class, () -> Suggestion.fromXContent(parser));
-            assertEquals("[1:31] unable to parse Suggestion with name [unknownType]: parser not found", e.getMessage());
+            assertEquals("[1:31] unknown field [unknownType]", e.getMessage());
         }
     }