Add an ignoreMissing parameter to IngestDocument's removeField method

modules/ingest-common/src/main/java/org/elasticsearch/ingest/common/RemoveProcessor.java

@@ -59,15 +59,9 @@ public IngestDocument execute(IngestDocument document) {
  }
 
  private void fieldsToRemoveProcessor(IngestDocument document) {
- // micro-optimization note: actual for-each loops here rather than a .forEach because it happens to be ~5% faster in benchmarks
- if (ignoreMissing) {
- for (TemplateScript.Factory field : fieldsToRemove) {
- removeWhenPresent(document, document.renderTemplate(field));
- }
- } else {
- for (TemplateScript.Factory field : fieldsToRemove) {
- document.removeField(document.renderTemplate(field));
- }
+ // micro-optimization note: actual for-each loop here rather than a .forEach because it happens to be ~5% faster in benchmarks
+ for (TemplateScript.Factory field : fieldsToRemove) {
+ document.removeField(document.renderTemplate(field), ignoreMissing);
  }
  }
 
@@ -76,13 +70,7 @@ private void fieldsToKeepProcessor(IngestDocument document) {
  .stream()
  .filter(documentField -> IngestDocument.Metadata.isMetadata(documentField) == false)
  .filter(documentField -> shouldKeep(documentField, fieldsToKeep, document) == false)
- .forEach(documentField -> removeWhenPresent(document, documentField));
- }
-
- private static void removeWhenPresent(IngestDocument document, String documentField) {
- if (document.hasField(documentField)) {
- document.removeField(documentField);
- }
+ .forEach(documentField -> document.removeField(documentField, true));
  }
 
  static boolean shouldKeep(String documentField, List<TemplateScript.Factory> fieldsToKeep, IngestDocument document) {

server/src/main/java/org/elasticsearch/ingest/IngestDocument.java

@@ -317,15 +317,29 @@ public boolean hasField(String path, boolean failOutOfRange) {
 
  /**
  * Removes the field identified by the provided path.
+ *
  * @param path the path of the field to be removed
  * @throws IllegalArgumentException if the path is null, empty, invalid or if the field doesn't exist.
  */
  public void removeField(String path) {
+ removeField(path, false);
+ }
+
+ /**
+ * Removes the field identified by the provided path.
+ *
+ * @param path the path of the field to be removed
+ * @param ignoreMissing The flag to determine whether to throw an exception when `path` is not found in the document.
+ * @throws IllegalArgumentException if the path is null, empty, or invalid; or if the field doesn't exist (and ignoreMissing is false).
+ */
+ public void removeField(String path, boolean ignoreMissing) {
  final FieldPath fieldPath = FieldPath.of(path);
  Object context = fieldPath.initialContext(this);
  ResolveResult result = resolve(fieldPath.pathElements, fieldPath.pathElements.length - 1, path, context);
  if (result.wasSuccessful) {
  context = result.resolvedObject;
+ } else if (ignoreMissing) {
+ return; // nothing was found, so there's nothing to remove :shrug:
  } else {
  throw new IllegalArgumentException(result.errorMessage);
  }
@@ -336,13 +350,13 @@ public void removeField(String path) {
  } else if (context instanceof IngestCtxMap map) { // optimization: handle IngestCtxMap separately from Map
  if (map.containsKey(leafKey)) {
  map.remove(leafKey);
- } else {
+ } else if (ignoreMissing == false) {
  throw new IllegalArgumentException(Errors.notPresent(path, leafKey));
  }
  } else if (context instanceof Map<?, ?> map) {
  if (map.containsKey(leafKey)) {
  map.remove(leafKey);
- } else {
+ } else if (ignoreMissing == false) {
  throw new IllegalArgumentException(Errors.notPresent(path, leafKey));
  }
  } else if (context instanceof List<?> list) {
@@ -353,11 +367,13 @@ public void removeField(String path) {
  throw new IllegalArgumentException(Errors.notInteger(path, leafKey), e);
  }
  if (index < 0 || index >= list.size()) {
- throw new IllegalArgumentException(Errors.outOfBounds(path, index, list.size()));
+ if (ignoreMissing == false) {
+ throw new IllegalArgumentException(Errors.outOfBounds(path, index, list.size()));
+ }
  } else {
  list.remove(index);
  }
- } else {
+ } else if (ignoreMissing == false) {
  throw new IllegalArgumentException(Errors.cannotRemove(path, leafKey, context));
  }
  }

server/src/test/java/org/elasticsearch/ingest/IngestDocumentTests.java

@@ -850,6 +850,23 @@ public void testRemoveField() {
  assertThat(document.getIngestMetadata().size(), equalTo(0));
  }
 
+ public void testRemoveFieldIgnoreMissing() {
+ document.removeField("foo", randomBoolean());
+ assertThat(document.getSourceAndMetadata().size(), equalTo(10));
+ assertThat(document.getSourceAndMetadata().containsKey("foo"), equalTo(false));
+ document.removeField("_index", randomBoolean());
+ assertThat(document.getSourceAndMetadata().size(), equalTo(9));
+ assertThat(document.getSourceAndMetadata().containsKey("_index"), equalTo(false));
+
+ // if ignoreMissing is false, we throw an exception for values that aren't found
+ IllegalArgumentException e;
+ e = expectThrows(IllegalArgumentException.class, () -> document.removeField("fizz.some.nonsense", false));
+ assertThat(e.getMessage(), is("field [some] not present as part of path [fizz.some.nonsense]"));
+
+ // but no exception is thrown if ignoreMissing is true
+ document.removeField("fizz.some.nonsense", true);
+ }
+
  public void testRemoveInnerField() {
  document.removeField("fizz.buzz");
  assertThat(document.getSourceAndMetadata().size(), equalTo(11));