Add fingerprint ingest processor

CHANGELOG.md

@@ -8,6 +8,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Add support for Azure Managed Identity in repository-azure ([#12423](https://github.com/opensearch-project/OpenSearch/issues/12423))
 - Add useCompoundFile index setting ([#13478](https://github.com/opensearch-project/OpenSearch/pull/13478))
 - Make outbound side of transport protocol dependent ([#13293](https://github.com/opensearch-project/OpenSearch/pull/13293))
+- Add fingerprint ingest processor ([#13724](https://github.com/opensearch-project/OpenSearch/pull/13724))
 
 ### Dependencies
 - Bump `com.github.spullara.mustache.java:compiler` from 0.9.10 to 0.9.13 ([#13329](https://github.com/opensearch-project/OpenSearch/pull/13329), [#13559](https://github.com/opensearch-project/OpenSearch/pull/13559))

modules/ingest-common/src/main/java/org/opensearch/ingest/common/FingerprintProcessor.java

@@ -0,0 +1,261 @@
+/*
+ * 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.ingest.common;
+
+import org.opensearch.common.Nullable;
+import org.opensearch.common.hash.MessageDigests;
+import org.opensearch.ingest.AbstractProcessor;
+import org.opensearch.ingest.ConfigurationUtils;
+import org.opensearch.ingest.IngestDocument;
+import org.opensearch.ingest.Processor;
+
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.util.Base64;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import static org.opensearch.ingest.ConfigurationUtils.newConfigurationException;
+
+/**
+ * Processor that generating hash value for the specified fields or all fields in a document
+ */
+public class FingerprintProcessor extends AbstractProcessor {
+    public static final String TYPE = "fingerprint";
+    private static final Set<String> HASH_METHODS = Set.of("MD5", "SHA-1", "SHA-256");
+
+    // fields used to generate hash value
+    private final List<String> fields;
+    // whether generate hash value for all fields in the document or not
+    private final boolean includeAllFields;
+    // the target field to store the hash value, defaults to fingerprint
+    private final String targetField;
+    // hash method used to generate the hash value, defaults to SHA-1
+    private final String hashMethod;
+    private final boolean ignoreMissing;
+
+    FingerprintProcessor(
+        String tag,
+        String description,
+        @Nullable List<String> fields,
+        boolean includeAllFields,
+        String targetField,
+        String hashMethod,
+        boolean ignoreMissing
+    ) {
+        super(tag, description);
+        if (fields != null) {
+            if (fields.isEmpty()) {
+                throw new IllegalArgumentException("fields cannot be empty");
+            }
+            if (fields.stream().anyMatch(Objects::isNull)) {
+                throw new IllegalArgumentException("field path cannot be null nor empty");
+            }
+            if (includeAllFields) {
+                throw new IllegalArgumentException("either fields or include_all_fields can be set");
+            }
+        } else if (!includeAllFields) {
+            throw new IllegalArgumentException("either fields or include_all_fields must be set");
+        }
+
+        if (!HASH_METHODS.contains(hashMethod.toUpperCase(Locale.ROOT))) {
+            throw new IllegalArgumentException("hash method must be MD5, SHA-1 or SHA-256");
+        }
+        this.fields = fields;
+        this.includeAllFields = includeAllFields;
+        this.targetField = targetField;
+        this.hashMethod = hashMethod;
+        this.ignoreMissing = ignoreMissing;
+    }
+
+    public List<String> getFields() {
+        return fields;
+    }
+
+    public boolean getIncludeAllFields() {
+        return includeAllFields;
+    }
+
+    public String getTargetField() {
+        return targetField;
+    }
+
+    public String getHashMethod() {
+        return hashMethod;
+    }
+
+    public boolean isIgnoreMissing() {
+        return ignoreMissing;
+    }
+
+    @Override
+    public IngestDocument execute(IngestDocument document) {
+        // we should deduplicate and sort the field names to make sure we can get consistent hash value
+        final List<String> sortedFields;
+        if (includeAllFields) {
+            Set<String> existingFields = new HashSet<>(document.getSourceAndMetadata().keySet());
+            Set<String> metadataFields = document.getMetadata()
+                .keySet()
+                .stream()
+                .map(IngestDocument.Metadata::getFieldName)
+                .collect(Collectors.toSet());
+            sortedFields = existingFields.stream().filter(field -> !metadataFields.contains(field)).sorted().collect(Collectors.toList());
+        } else {
+            sortedFields = fields.stream().distinct().sorted().collect(Collectors.toList());
+        }
+        assert (!sortedFields.isEmpty());
+
+        final StringBuilder concatenatedFields = new StringBuilder();
+        sortedFields.forEach(field -> {
+            if (!document.hasField(field)) {
+                if (ignoreMissing) {
+                    return;
+                } else {
+                    throw new IllegalArgumentException("field [" + field + "] doesn't exist");
+                }
+            }
+
+            final Object value = document.getFieldValue(field, Object.class);
+            if (value instanceof Map) {
+                @SuppressWarnings("unchecked")
+                Map<String, Object> flattenedMap = toFlattenedMap((Map<String, Object>) value);
+                flattenedMap.entrySet()
+                    .stream()
+                    .sorted(Map.Entry.comparingByKey())
+                    .forEach(
+                        entry -> concatenatedFields.append("|")
+                            .append(field)
+                            .append(".")
+                            .append(entry.getKey())
+                            .append("|")
+                            .append(entry.getValue())
+                    );
+            } else {
+                concatenatedFields.append("|").append(field).append("|").append(value);
+            }
+        });
+        // if all specified fields don't exist and ignore_missing is true, then do nothing
+        if (concatenatedFields.length() == 0) {
+            return document;
+        }
+        concatenatedFields.append("|");
+
+        MessageDigest messageDigest = HashMethod.fromMethodName(hashMethod);
+        assert (messageDigest != null);
+        messageDigest.update(concatenatedFields.toString().getBytes(StandardCharsets.UTF_8));
+        document.setFieldValue(targetField, Base64.getEncoder().encodeToString(messageDigest.digest()));
+
+        return document;
+    }
+
+    @Override
+    public String getType() {
+        return TYPE;
+    }
+
+    /**
+     * Convert a map containing nested fields to a flattened map,
+     * for example, if the original map is
+     * {
+     *     "a": {
+     *         "b": 1,
+     *         "c": 2
+     *     }
+     * }, then the converted map is
+     * {
+     *     "a.b": 1,
+     *     "a.c": 2
+     * }
+     * @param map the original map which may contain nested fields
+     * @return a flattened map which has only one level fields
+     */
+    @SuppressWarnings("unchecked")
+    private Map<String, Object> toFlattenedMap(Map<String, Object> map) {
+        Map<String, Object> flattenedMap = new HashMap<>();
+        for (Map.Entry<String, Object> entry : map.entrySet()) {
+            if (entry.getValue() instanceof Map) {
+                toFlattenedMap((Map<String, Object>) entry.getValue()).forEach(
+                    (key, value) -> flattenedMap.put(entry.getKey() + "." + key, value)
+                );
+            } else {
+                flattenedMap.put(entry.getKey(), entry.getValue());
+            }
+        }
+        return flattenedMap;
+    }
+
+    /**
+     * The supported hash methods used to generate hash value
+     */
+    enum HashMethod {
+        MD5(MessageDigests.md5()),
+        SHA1(MessageDigests.sha1()),
+        SHA256(MessageDigests.sha256());
+
+        private final MessageDigest messageDigest;
+
+        HashMethod(MessageDigest messageDigest) {
+            this.messageDigest = messageDigest;
+        }
+
+        public static MessageDigest fromMethodName(String methodName) {
+            String name = methodName.toUpperCase(Locale.ROOT);
+            switch (name) {
+                case "MD5":
+                    return MD5.messageDigest;
+                case "SHA-1":
+                    return SHA1.messageDigest;
+                case "SHA-256":
+                    return SHA256.messageDigest;
+                default:
+                    return null;
+            }
+        }
+    }
+
+    public static final class Factory implements Processor.Factory {
+        @Override
+        public FingerprintProcessor create(
+            Map<String, Processor.Factory> registry,
+            String processorTag,
+            String description,
+            Map<String, Object> config
+        ) throws Exception {
+            List<String> fields = ConfigurationUtils.readOptionalList(TYPE, processorTag, config, "fields");
+            boolean includeAllFields = ConfigurationUtils.readBooleanProperty(TYPE, processorTag, config, "include_all_fields", false);
+            if (fields != null) {
+                if (fields.isEmpty()) {
+                    throw newConfigurationException(TYPE, processorTag, "fields", "fields cannot be empty");
+                }
+                if (fields.stream().anyMatch(Objects::isNull)) {
+                    throw newConfigurationException(TYPE, processorTag, "fields", "field path cannot be null nor empty");
+                }
+                if (includeAllFields) {
+                    throw newConfigurationException(TYPE, processorTag, "fields", "either fields or include_all_fields can be set");
+                }
+            } else if (!includeAllFields) {
+                throw newConfigurationException(TYPE, processorTag, "fields", "either fields or include_all_fields must be set");
+            }
+
+            String targetField = ConfigurationUtils.readStringProperty(TYPE, processorTag, config, "target_field", "fingerprint");
+            String hashMethod = ConfigurationUtils.readStringProperty(TYPE, processorTag, config, "hash_method", "SHA-1");
+            if (!HASH_METHODS.contains(hashMethod.toUpperCase(Locale.ROOT))) {
+                throw newConfigurationException(TYPE, processorTag, "hash_method", "hash method must be MD5, SHA-1 or SHA-256");
+            }
+            boolean ignoreMissing = ConfigurationUtils.readBooleanProperty(TYPE, processorTag, config, "ignore_missing", false);
+            return new FingerprintProcessor(processorTag, description, fields, includeAllFields, targetField, hashMethod, ignoreMissing);
+        }
+    }
+}

modules/ingest-common/src/main/java/org/opensearch/ingest/common/IngestCommonModulePlugin.java

@@ -109,6 +109,7 @@ public Map<String, Processor.Factory> getProcessors(Processor.Parameters paramet
         processors.put(CopyProcessor.TYPE, new CopyProcessor.Factory(parameters.scriptService));
         processors.put(RemoveByPatternProcessor.TYPE, new RemoveByPatternProcessor.Factory());
         processors.put(CommunityIdProcessor.TYPE, new CommunityIdProcessor.Factory());
+        processors.put(FingerprintProcessor.TYPE, new FingerprintProcessor.Factory());
         return Collections.unmodifiableMap(processors);
     }
 

modules/ingest-common/src/test/java/org/opensearch/ingest/common/FingerprintProcessorFactoryTests.java

@@ -0,0 +1,113 @@
+/*
+ * 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.ingest.common;
+
+import org.opensearch.OpenSearchParseException;
+import org.opensearch.test.OpenSearchTestCase;
+import org.junit.Before;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+
+public class FingerprintProcessorFactoryTests extends OpenSearchTestCase {
+
+    private FingerprintProcessor.Factory factory;
+
+    @Before
+    public void init() {
+        factory = new FingerprintProcessor.Factory();
+    }
+
+    public void testCreate() throws Exception {
+        Map<String, Object> config = new HashMap<>();
+
+        boolean includeAllFields = randomBoolean();
+        List<String> fields = null;
+        if (!includeAllFields) {
+            fields = List.of(randomAlphaOfLength(10));
+            config.put("fields", fields);
+        } else {
+            config.put("include_all_fields", true);
+        }
+
+        String targetField = null;
+        if (randomBoolean()) {
+            targetField = randomAlphaOfLength(10);
+        }
+        config.put("target_field", targetField);
+
+        boolean ignoreMissing = randomBoolean();
+        config.put("ignore_missing", ignoreMissing);
+        String processorTag = randomAlphaOfLength(10);
+        FingerprintProcessor fingerprintProcessor = factory.create(null, processorTag, null, config);
+        assertThat(fingerprintProcessor.getTag(), equalTo(processorTag));
+        assertThat(fingerprintProcessor.getFields(), equalTo(fields));
+        assertThat(fingerprintProcessor.getIncludeAllFields(), equalTo(includeAllFields));
+        assertThat(fingerprintProcessor.getTargetField(), equalTo(Objects.requireNonNullElse(targetField, "fingerprint")));
+        assertThat(fingerprintProcessor.isIgnoreMissing(), equalTo(ignoreMissing));
+    }
+
+    public void testCreateWithFields() throws Exception {
+        Map<String, Object> config = new HashMap<>();
+        try {
+            factory.create(null, null, null, config);
+            fail("factory create should have failed");
+        } catch (OpenSearchParseException e) {
+            assertThat(e.getMessage(), equalTo("[fields] either fields or include_all_fields must be set"));
+        }
+
+        config.put("fields", Collections.emptyList());
+        try {
+            factory.create(null, null, null, config);
+            fail("factory create should have failed");
+        } catch (OpenSearchParseException e) {
+            assertThat(e.getMessage(), equalTo("[fields] fields cannot be empty"));
+        }
+
+        config = new HashMap<>();
+        config.put("fields", List.of(randomAlphaOfLength(10)));
+        config.put("include_all_fields", true);
+        try {
+            factory.create(null, null, null, config);
+            fail("factory create should have failed");
+        } catch (OpenSearchParseException e) {
+            assertThat(e.getMessage(), equalTo("[fields] either fields or include_all_fields can be set"));
+        }
+
+        config = new HashMap<>();
+        List<String> fields = new ArrayList<>();
+        fields.add(null);
+        config.put("fields", fields);
+        try {
+            factory.create(null, null, null, config);
+            fail("factory create should have failed");
+        } catch (OpenSearchParseException e) {
+            assertThat(e.getMessage(), equalTo("[fields] field path cannot be null nor empty"));
+        }
+    }
+
+    public void testCreateWithHashMethod() throws Exception {
+        Map<String, Object> config = new HashMap<>();
+        List<String> fields = List.of(randomAlphaOfLength(10));
+        config.put("fields", fields);
+        config.put("hash_method", randomAlphaOfLength(10));
+        try {
+            factory.create(null, null, null, config);
+            fail("factory create should have failed");
+        } catch (OpenSearchParseException e) {
+            assertThat(e.getMessage(), equalTo("[hash_method] hash method must be MD5, SHA-1 or SHA-256"));
+        }
+    }
+}