Delete file changes

Signed-off-by: Stephen Crawford <[email protected]>

modules/search-pipeline-common/src/main/java/org/opensearch/search/pipeline/common/DeleteFieldResponseProcessor.java

@@ -0,0 +1,139 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.search.pipeline.common;
+
+import org.opensearch.action.search.SearchRequest;
+import org.opensearch.action.search.SearchResponse;
+import org.opensearch.common.collect.Tuple;
+import org.opensearch.common.document.DocumentField;
+import org.opensearch.common.xcontent.XContentHelper;
+import org.opensearch.core.common.bytes.BytesReference;
+import org.opensearch.core.xcontent.MediaType;
+import org.opensearch.core.xcontent.XContentBuilder;
+import org.opensearch.ingest.ConfigurationUtils;
+import org.opensearch.search.SearchHit;
+import org.opensearch.search.pipeline.AbstractProcessor;
+import org.opensearch.search.pipeline.Processor;
+import org.opensearch.search.pipeline.SearchRequestProcessor;
+import org.opensearch.search.pipeline.SearchResponseProcessor;
+
+import java.util.Map;
+
+/**
+ * This is a {@link SearchRequestProcessor} that renames a field before returning the search response
+ */
+public class DeleteFieldResponseProcessor extends AbstractProcessor implements SearchResponseProcessor {
+
+    private final String field;
+    private final boolean ignoreMissing;
+
+    /**
+     * Key to reference this processor type from a search pipeline.
+     */
+    public static final String TYPE = "delete_field";
+
+    /**
+     * Constructor that takes a target field to be deleted
+     *
+     * @param tag            processor tag
+     * @param description    processor description
+     * @param ignoreFailure  option to ignore failure
+     * @param field        name of field to delete
+     * @param ignoreMissing if true, do not throw error if oldField does not exist within search response
+     */
+    public DeleteFieldResponseProcessor(String tag, String description, boolean ignoreFailure, String field, boolean ignoreMissing) {
+        super(tag, description, ignoreFailure);
+        this.field = field;
+        this.ignoreMissing = ignoreMissing;
+    }
+
+    @Override
+    public String getType() {
+        return TYPE;
+    }
+
+    /**
+     * Get the provided field to be deleted
+     * @return oldField
+     */
+    public String getField() {
+        return field;
+    }
+
+    /**
+     * Getter function for ignoreMissing
+     * @return ignoreMissing
+     */
+    public boolean isIgnoreMissing() {
+        return ignoreMissing;
+    }
+
+    @Override
+    public SearchResponse processResponse(SearchRequest request, SearchResponse response) throws Exception {
+        boolean foundField = false;
+
+        SearchHit[] hits = response.getHits().getHits();
+        for (SearchHit hit : hits) {
+            Map<String, DocumentField> fields = hit.getFields();
+            if (fields.containsKey(field)) {
+                foundField = true;
+                DocumentField old = hit.removeDocumentField(field);
+            }
+
+            if (hit.hasSource()) {
+                BytesReference sourceRef = hit.getSourceRef();
+                Tuple<? extends MediaType, Map<String, Object>> typeAndSourceMap = XContentHelper.convertToMap(
+                    sourceRef,
+                    false,
+                    (MediaType) null
+                );
+
+                Map<String, Object> sourceAsMap = typeAndSourceMap.v2();
+                if (sourceAsMap.containsKey(field)) {
+                    foundField = true;
+                    Object val = sourceAsMap.remove(field);
+                    XContentBuilder builder = XContentBuilder.builder(typeAndSourceMap.v1().xContent());
+                    builder.map(sourceAsMap);
+                    hit.sourceRef(BytesReference.bytes(builder));
+                }
+            }
+
+            if (!foundField && !ignoreMissing) {
+                throw new IllegalArgumentException("Document with id " + hit.getId() + " is missing field " + field);
+            }
+        }
+
+        return response;
+    }
+
+    /**
+     * This is a factory that creates the DeleteFieldResponseProcessor
+     */
+    public static final class Factory implements Processor.Factory<SearchResponseProcessor> {
+
+        /**
+         * Constructor for factory
+         */
+        Factory() {}
+
+        @Override
+        public DeleteFieldResponseProcessor create(
+            Map<String, Processor.Factory<SearchResponseProcessor>> processorFactories,
+            String tag,
+            String description,
+            boolean ignoreFailure,
+            Map<String, Object> config,
+            PipelineContext pipelineContext
+        ) throws Exception {
+            String field = ConfigurationUtils.readStringProperty(TYPE, tag, config, "field");
+            boolean ignoreMissing = ConfigurationUtils.readBooleanProperty(TYPE, tag, config, "ignore_missing", false);
+            return new DeleteFieldResponseProcessor(tag, description, ignoreFailure, field, ignoreMissing);
+        }
+    }
+}

modules/search-pipeline-common/src/main/java/org/opensearch/search/pipeline/common/SearchPipelineCommonModulePlugin.java

@@ -44,6 +44,9 @@ public Map<String, Processor.Factory<SearchRequestProcessor>> getRequestProcesso
 
     @Override
     public Map<String, Processor.Factory<SearchResponseProcessor>> getResponseProcessors(Parameters parameters) {
-        return Map.of(RenameFieldResponseProcessor.TYPE, new RenameFieldResponseProcessor.Factory());
+        return Map.of(RenameFieldResponseProcessor.TYPE,
+                new RenameFieldResponseProcessor.Factory(),
+                DeleteFieldResponseProcessor.TYPE,
+                new DeleteFieldResponseProcessor.Factory());
     }
 }