NIFI-4717: Several minor bug fixes and performance improvements around record-oriented processors

Signed-off-by: Matthew Burgess <mattyb149@apache.org>

This closes #2359

nifi-commons/nifi-record/src/main/java/org/apache/nifi/serialization/SimpleRecordSchema.java

@@ -23,7 +23,6 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
-import java.util.OptionalInt;
 import java.util.stream.Collectors;
 
 import org.apache.nifi.serialization.record.DataType;
@@ -33,7 +32,7 @@ import org.apache.nifi.serialization.record.SchemaIdentifier;
 
 public class SimpleRecordSchema implements RecordSchema {
     private List<RecordField> fields = null;
-    private Map<String, Integer> fieldIndices = null;
+    private Map<String, RecordField> fieldMap = null;
     private final boolean textAvailable;
     private final String text;
     private final String schemaFormat;
@@ -88,29 +87,25 @@ public class SimpleRecordSchema implements RecordSchema {
     }
 
     public void setFields(final List<RecordField> fields) {
-
         if (this.fields != null) {
             throw new IllegalArgumentException("Fields have already been set.");
         }
 
         this.fields = Collections.unmodifiableList(new ArrayList<>(fields));
-        this.fieldIndices = new HashMap<>(fields.size());
+        this.fieldMap = new HashMap<>(fields.size() * 2);
 
-        int index = 0;
         for (final RecordField field : fields) {
-            Integer previousValue = fieldIndices.put(field.getFieldName(), index);
+            RecordField previousValue = fieldMap.put(field.getFieldName(), field);
             if (previousValue != null) {
                 throw new IllegalArgumentException("Two fields are given with the same name (or alias) of '" + field.getFieldName() + "'");
             }
 
             for (final String alias : field.getAliases()) {
-                previousValue = fieldIndices.put(alias, index);
+                previousValue = fieldMap.put(alias, field);
                 if (previousValue != null) {
                     throw new IllegalArgumentException("Two fields are given with the same name (or alias) of '" + field.getFieldName() + "'");
                 }
             }
-
-            index++;
         }
     }
 
@@ -138,24 +133,18 @@ public class SimpleRecordSchema implements RecordSchema {
 
     @Override
     public Optional<DataType> getDataType(final String fieldName) {
-        final OptionalInt idx = getFieldIndex(fieldName);
+        final RecordField field = fieldMap.get(fieldName);
-        return idx.isPresent() ? Optional.of(fields.get(idx.getAsInt()).getDataType()) : Optional.empty();
+        if (field == null) {
+            return Optional.empty();
+        }
+        return Optional.of(field.getDataType());
     }
 
     @Override
     public Optional<RecordField> getField(final String fieldName) {
-        final OptionalInt indexOption = getFieldIndex(fieldName);
+        return Optional.ofNullable(fieldMap.get(fieldName));
-        if (indexOption.isPresent()) {
-            return Optional.of(fields.get(indexOption.getAsInt()));
     }
 
-        return Optional.empty();
-    }
-
-    private OptionalInt getFieldIndex(final String fieldName) {
-        final Integer index = fieldIndices.get(fieldName);
-        return index == null ? OptionalInt.empty() : OptionalInt.of(index);
-    }
 
     @Override
     public boolean equals(final Object obj) {

nifi-commons/nifi-record/src/main/java/org/apache/nifi/serialization/record/MapRecord.java

@@ -70,10 +70,10 @@ public class MapRecord implements Record {
 
     private Map<String, Object> checkTypes(final Map<String, Object> values, final RecordSchema schema) {
         for (final RecordField field : schema.getFields()) {
-            final Object value = getExplicitValue(field, values);
+            Object value = getExplicitValue(field, values);
 
             if (value == null) {
-                if (field.isNullable()) {
+                if (field.isNullable() || field.getDefaultValue() != null) {
                     continue;
                 }
 
@@ -109,7 +109,12 @@ public class MapRecord implements Record {
         final Object[] values = new Object[schema.getFieldCount()];
         int i = 0;
         for (final RecordField recordField : schema.getFields()) {
-            values[i++] = getValue(recordField);
+            Object value = getExplicitValue(recordField);
+            if (value == null) {
+                value = recordField.getDefaultValue();
+            }
+
+            values[i++] = value;
         }
         return values;
     }

nifi-commons/nifi-record/src/main/java/org/apache/nifi/serialization/record/RecordField.java

@@ -68,7 +68,15 @@ public class RecordField {
 
         this.fieldName = Objects.requireNonNull(fieldName);
         this.dataType = Objects.requireNonNull(dataType);
-        this.aliases = Collections.unmodifiableSet(Objects.requireNonNull(aliases));
+
+        // If aliases is the empty set, don't bother with the expense of wrapping in an unmodifiableSet.
+        Objects.requireNonNull(aliases);
+        if ((Set<?>) aliases == Collections.EMPTY_SET) {
+            this.aliases = aliases;
+        } else {
+            this.aliases = Collections.unmodifiableSet(aliases);
+        }
+
         this.defaultValue = defaultValue;
         this.nullable = nullable;
     }

nifi-commons/nifi-record/src/main/java/org/apache/nifi/serialization/record/ResultSetRecordSet.java

@@ -31,6 +31,8 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 import org.apache.nifi.serialization.SimpleRecordSchema;
 import org.slf4j.Logger;
@@ -174,7 +176,13 @@ public class ResultSetRecordSet implements RecordSet, Closeable {
 
                 final Object obj = rs.getObject(columnIndex);
                 if (obj == null || !(obj instanceof Record)) {
-                    return RecordFieldType.RECORD.getDataType();
+                    final List<DataType> dataTypes = Stream.of(RecordFieldType.BIGINT, RecordFieldType.BOOLEAN, RecordFieldType.BYTE, RecordFieldType.CHAR, RecordFieldType.DATE,
+                        RecordFieldType.DOUBLE, RecordFieldType.FLOAT, RecordFieldType.INT, RecordFieldType.LONG, RecordFieldType.SHORT, RecordFieldType.STRING, RecordFieldType.TIME,
+                        RecordFieldType.TIMESTAMP)
+                    .map(recordFieldType -> recordFieldType.getDataType())
+                    .collect(Collectors.toList());
+
+                    return RecordFieldType.CHOICE.getChoiceDataType(dataTypes);
                 }
 
                 final Record record = (Record) obj;

nifi-commons/nifi-record/src/main/java/org/apache/nifi/serialization/record/util/DataTypeUtils.java

@@ -891,6 +891,9 @@ public class DataTypeUtils {
         if (otherSchema == null) {
             return thisSchema;
         }
+        if (thisSchema == otherSchema) {
+            return thisSchema;
+        }
 
         final List<RecordField> otherFields = otherSchema.getFields();
         if (otherFields.isEmpty()) {

nifi-mock/src/main/java/org/apache/nifi/util/MockPropertyValue.java

@@ -225,7 +225,7 @@ public class MockPropertyValue implements PropertyValue {
 
     @Override
     public boolean isExpressionLanguagePresent() {
-        if (!expectExpressions) {
+        if (!Boolean.TRUE.equals(expectExpressions)) {
             return false;
         }
 

nifi-nar-bundles/nifi-extension-utils/nifi-record-utils/nifi-avro-record-utils/src/main/java/org/apache/nifi/avro/AvroTypeUtil.java

@@ -27,9 +27,11 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Function;
 import java.util.stream.Collectors;
@@ -150,9 +152,20 @@ public class AvroTypeUtil {
                 final ChoiceDataType choiceDataType = (ChoiceDataType) dataType;
                 final List<DataType> options = choiceDataType.getPossibleSubTypes();
 
+                // We need to keep track of which types have been added to the union, because if we have
+                // two elements in the UNION with the same type, it will fail - even if the logical type is
+                // different. So if we have an int and a logical type date (which also has a 'concrete type' of int)
+                // then an Exception will be thrown when we try to create the union. To avoid this, we just keep track
+                // of the Types and avoid adding it in such a case.
                 final List<Schema> unionTypes = new ArrayList<>(options.size());
+                final Set<Type> typesAdded = new HashSet<>();
+
                 for (final DataType option : options) {
-                    unionTypes.add(buildAvroSchema(option, fieldName, false));
+                    final Schema optionSchema = buildAvroSchema(option, fieldName, false);
+                    if (!typesAdded.contains(optionSchema.getType())) {
+                        unionTypes.add(optionSchema);
+                        typesAdded.add(optionSchema.getType());
+                    }
                 }
 
                 schema = Schema.createUnion(unionTypes);
@@ -213,6 +226,17 @@ public class AvroTypeUtil {
     }
 
     private static Schema nullable(final Schema schema) {
+        if (schema.getType() == Type.UNION) {
+            final List<Schema> unionTypes = new ArrayList<>(schema.getTypes());
+            final Schema nullSchema = Schema.create(Type.NULL);
+            if (unionTypes.contains(nullSchema)) {
+                return schema;
+            }
+
+            unionTypes.add(nullSchema);
+            return Schema.createUnion(unionTypes);
+        }
+
         return Schema.createUnion(Schema.create(Type.NULL), schema);
     }
 

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/QueryRecord.java

@@ -453,6 +453,8 @@ public class QueryRecord extends AbstractProcessor {
         return new QueryResult() {
             @Override
             public void close() throws IOException {
+                table.close();
+
                 final BlockingQueue<CachedStatement> statementQueue = statementQueues.get(sql);
                 if (statementQueue == null || !statementQueue.offer(cachedStatement)) {
                     try {

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/UpdateRecord.java

@@ -165,7 +165,9 @@ public class UpdateRecord extends AbstractRecordProcessor {
                 }
             } else {
                 final PropertyValue replacementValue = context.getProperty(recordPathText);
-                final Map<String, String> fieldVariables = new HashMap<>(4);
+
+                if (replacementValue.isExpressionLanguagePresent()) {
+                    final Map<String, String> fieldVariables = new HashMap<>();
 
                     result.getSelectedFields().forEach(fieldVal -> {
                         fieldVariables.clear();
@@ -176,6 +178,10 @@ public class UpdateRecord extends AbstractRecordProcessor {
                         final String evaluatedReplacementVal = replacementValue.evaluateAttributeExpressions(flowFile, fieldVariables).getValue();
                         fieldVal.updateValue(evaluatedReplacementVal);
                     });
+                } else {
+                    final String evaluatedReplacementVal = replacementValue.getValue();
+                    result.getSelectedFields().forEach(fieldVal -> fieldVal.updateValue(evaluatedReplacementVal));
+                }
             }
         }
 

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/queryrecord/FlowFileTable.java

@@ -18,9 +18,12 @@ package org.apache.nifi.queryrecord;
 
 import java.io.InputStream;
 import java.lang.reflect.Type;
+import java.math.BigInteger;
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 import org.apache.calcite.adapter.java.JavaTypeFactory;
 import org.apache.calcite.linq4j.AbstractEnumerable;
@@ -47,6 +50,7 @@ import org.apache.nifi.processor.exception.ProcessException;
 import org.apache.nifi.serialization.RecordReader;
 import org.apache.nifi.serialization.RecordReaderFactory;
 import org.apache.nifi.serialization.record.DataType;
+import org.apache.nifi.serialization.record.Record;
 import org.apache.nifi.serialization.record.RecordField;
 import org.apache.nifi.serialization.record.RecordSchema;
 
@@ -63,6 +67,8 @@ public class FlowFileTable<S, E> extends AbstractTable implements QueryableTable
     private volatile FlowFile flowFile;
     private volatile int maxRecordsRead;
 
+    private final Set<FlowFileEnumerator<?>> enumerators = new HashSet<>();
+
     /**
      * Creates a FlowFile table.
      */
@@ -85,6 +91,14 @@ public class FlowFileTable<S, E> extends AbstractTable implements QueryableTable
         return "FlowFileTable";
     }
 
+    public void close() {
+        synchronized (enumerators) {
+            for (final FlowFileEnumerator<?> enumerator : enumerators) {
+                enumerator.close();
+            }
+        }
+    }
+
     /**
      * Returns an enumerable over a given projection of the fields.
      *
@@ -96,7 +110,7 @@ public class FlowFileTable<S, E> extends AbstractTable implements QueryableTable
             @Override
             @SuppressWarnings({"unchecked", "rawtypes"})
             public Enumerator<Object> enumerator() {
-                return new FlowFileEnumerator(session, flowFile, logger, recordParserFactory, fields) {
+                final FlowFileEnumerator flowFileEnumerator = new FlowFileEnumerator(session, flowFile, logger, recordParserFactory, fields) {
                     @Override
                     protected void onFinish() {
                         final int recordCount = getRecordsRead();
@@ -104,7 +118,21 @@ public class FlowFileTable<S, E> extends AbstractTable implements QueryableTable
                             maxRecordsRead = recordCount;
                         }
                     }
+
+                    @Override
+                    public void close() {
+                        synchronized (enumerators) {
+                            enumerators.remove(this);
+                        }
+                        super.close();
+                    }
                 };
+
+                synchronized (enumerators) {
+                    enumerators.add(flowFileEnumerator);
+                }
+
+                return flowFileEnumerator;
             }
         };
     }
@@ -203,9 +231,13 @@ public class FlowFileTable<S, E> extends AbstractTable implements QueryableTable
             case ARRAY:
                 return typeFactory.createJavaType(Object[].class);
             case RECORD:
-                return typeFactory.createJavaType(Object.class);
+                return typeFactory.createJavaType(Record.class);
             case MAP:
                 return typeFactory.createJavaType(HashMap.class);
+            case BIGINT:
+                return typeFactory.createJavaType(BigInteger.class);
+            case CHOICE:
+                return typeFactory.createJavaType(Object.class);
         }
 
         throw new IllegalArgumentException("Unknown Record Field Type: " + fieldType);

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/java/org/apache/nifi/processors/standard/TestUpdateRecord.java

@@ -64,6 +64,7 @@ public class TestUpdateRecord {
     public void testLiteralReplacementValue() {
         runner.setProperty("/name", "Jane Doe");
         runner.enqueue("");
+        runner.setValidateExpressionUsage(false);
 
         readerService.addRecord("John Doe", 35);
         runner.run();
@@ -188,6 +189,7 @@ public class TestUpdateRecord {
     public void testUpdateInArray() throws InitializationException, IOException {
         final JsonTreeReader jsonReader = new JsonTreeReader();
         runner.addControllerService("reader", jsonReader);
+        runner.setValidateExpressionUsage(false);
 
         final String inputSchemaText = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/schema/person-with-address.avsc")));
         final String outputSchemaText = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/schema/person-with-address.avsc")));
@@ -218,6 +220,7 @@ public class TestUpdateRecord {
     public void testUpdateInNullArray() throws InitializationException, IOException {
         final JsonTreeReader jsonReader = new JsonTreeReader();
         runner.addControllerService("reader", jsonReader);
+        runner.setValidateExpressionUsage(false);
 
         final String inputSchemaText = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/schema/person-with-address.avsc")));
         final String outputSchemaText = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/schema/person-with-address.avsc")));

nifi-nar-bundles/nifi-standard-services/nifi-record-serialization-services-bundle/nifi-record-serialization-services/src/main/java/org/apache/nifi/csv/CSVRecordReader.java

@@ -23,7 +23,7 @@ import java.io.InputStreamReader;
 import java.io.Reader;
 import java.text.DateFormat;
 import java.util.ArrayList;
-import java.util.LinkedHashMap;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
@@ -41,6 +41,8 @@ import org.apache.nifi.serialization.RecordReader;
 import org.apache.nifi.serialization.record.DataType;
 import org.apache.nifi.serialization.record.MapRecord;
 import org.apache.nifi.serialization.record.Record;
+import org.apache.nifi.serialization.record.RecordField;
+import org.apache.nifi.serialization.record.RecordFieldType;
 import org.apache.nifi.serialization.record.RecordSchema;
 import org.apache.nifi.serialization.record.util.DataTypeUtils;
 
@@ -53,7 +55,7 @@ public class CSVRecordReader implements RecordReader {
     private final Supplier<DateFormat> LAZY_TIME_FORMAT;
     private final Supplier<DateFormat> LAZY_TIMESTAMP_FORMAT;
 
-    private List<String> rawFieldNames;
+    private List<RecordField> recordFields;
 
     public CSVRecordReader(final InputStream in, final ComponentLog logger, final RecordSchema schema, final CSVFormat csvFormat, final boolean hasHeader, final boolean ignoreHeader,
         final String dateFormat, final String timeFormat, final String timestampFormat, final String encoding) throws IOException {
@@ -87,31 +89,37 @@ public class CSVRecordReader implements RecordReader {
     public Record nextRecord(final boolean coerceTypes, final boolean dropUnknownFields) throws IOException, MalformedRecordException {
         final RecordSchema schema = getSchema();
 
-        final List<String> rawFieldNames = getRawFieldNames();
+        final List<RecordField> recordFields = getRecordFields();
-        final int numFieldNames = rawFieldNames.size();
+        final int numFieldNames = recordFields.size();
 
         for (final CSVRecord csvRecord : csvParser) {
-            final Map<String, Object> values = new LinkedHashMap<>();
+            final Map<String, Object> values = new HashMap<>(recordFields.size() * 2);
             for (int i = 0; i < csvRecord.size(); i++) {
-                final String rawFieldName = numFieldNames <= i ? "unknown_field_index_" + i : rawFieldNames.get(i);
                 final String rawValue = csvRecord.get(i);
 
-                final Optional<DataType> dataTypeOption = schema.getDataType(rawFieldName);
+                final String rawFieldName;
-
+                final DataType dataType;
-                if (!dataTypeOption.isPresent() && dropUnknownFields) {
+                if (i >= numFieldNames) {
-                    continue;
+                    if (!dropUnknownFields) {
+                        values.put("unknown_field_index_" + i, rawValue);
                     }
 
+                    continue;
+                } else {
+                    final RecordField recordField = recordFields.get(i);
+                    rawFieldName = recordField.getFieldName();
+                    dataType = recordField.getDataType();
+                }
+
+
                 final Object value;
-                if (coerceTypes && dataTypeOption.isPresent()) {
+                if (coerceTypes) {
-                    value = convert(rawValue, dataTypeOption.get(), rawFieldName);
+                    value = convert(rawValue, dataType, rawFieldName);
-                } else if (dataTypeOption.isPresent()) {
+                } else {
                     // The CSV Reader is going to return all fields as Strings, because CSV doesn't have any way to
                     // dictate a field type. As a result, we will use the schema that we have to attempt to convert
                     // the value into the desired type if it's a simple type.
-                    value = convertSimpleIfPossible(rawValue, dataTypeOption.get(), rawFieldName);
+                    value = convertSimpleIfPossible(rawValue, dataType, rawFieldName);
-                } else {
-                    value = rawValue;
                 }
 
                 values.put(rawFieldName, value);
@@ -124,9 +132,9 @@ public class CSVRecordReader implements RecordReader {
     }
 
 
-    private List<String> getRawFieldNames() {
+    private List<RecordField> getRecordFields() {
-        if (this.rawFieldNames != null) {
+        if (this.recordFields != null) {
-            return this.rawFieldNames;
+            return this.recordFields;
         }
 
         // Use a SortedMap keyed by index of the field so that we can get a List of field names in the correct order
@@ -135,8 +143,19 @@ public class CSVRecordReader implements RecordReader {
             sortedMap.put(entry.getValue(), entry.getKey());
         }
 
-        this.rawFieldNames = new ArrayList<>(sortedMap.values());
+        final List<RecordField> fields = new ArrayList<>();
-        return this.rawFieldNames;
+        final List<String> rawFieldNames = new ArrayList<>(sortedMap.values());
+        for (final String rawFieldName : rawFieldNames) {
+            final Optional<RecordField> option = schema.getField(rawFieldName);
+            if (option.isPresent()) {
+                fields.add(option.get());
+            } else {
+                fields.add(new RecordField(rawFieldName, RecordFieldType.STRING.getDataType()));
+            }
+        }
+
+        this.recordFields = fields;
+        return fields;
     }
 
 

nifi-nar-bundles/nifi-standard-services/nifi-record-serialization-services-bundle/nifi-record-serialization-services/src/main/java/org/apache/nifi/csv/JacksonCSVRecordReader.java

@@ -17,11 +17,19 @@
 
 package org.apache.nifi.csv;
 
-import com.fasterxml.jackson.databind.MappingIterator;
+import java.io.IOException;
-import com.fasterxml.jackson.databind.ObjectReader;
+import java.io.InputStream;
-import com.fasterxml.jackson.dataformat.csv.CsvMapper;
+import java.io.InputStreamReader;
-import com.fasterxml.jackson.dataformat.csv.CsvParser;
+import java.io.Reader;
-import com.fasterxml.jackson.dataformat.csv.CsvSchema;
+import java.text.DateFormat;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.function.Supplier;
+
 import org.apache.commons.csv.CSVFormat;
 import org.apache.commons.io.input.BOMInputStream;
 import org.apache.commons.lang3.CharUtils;
@@ -35,18 +43,11 @@ import org.apache.nifi.serialization.record.Record;
 import org.apache.nifi.serialization.record.RecordSchema;
 import org.apache.nifi.serialization.record.util.DataTypeUtils;
 
-import java.io.IOException;
+import com.fasterxml.jackson.databind.MappingIterator;
-import java.io.InputStream;
+import com.fasterxml.jackson.databind.ObjectReader;
-import java.io.InputStreamReader;
+import com.fasterxml.jackson.dataformat.csv.CsvMapper;
-import java.io.Reader;
+import com.fasterxml.jackson.dataformat.csv.CsvParser;
-import java.text.DateFormat;
+import com.fasterxml.jackson.dataformat.csv.CsvSchema;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
-import java.util.function.Supplier;
 
 
 public class JacksonCSVRecordReader implements RecordReader {
@@ -140,6 +141,7 @@ public class JacksonCSVRecordReader implements RecordReader {
                     }
                 }
             }
+
             // Check for empty lines and ignore them
             boolean foundRecord = true;
             if (csvRecord == null || (csvRecord.length == 1 && StringUtils.isEmpty(csvRecord[0]))) {
@@ -154,12 +156,13 @@ public class JacksonCSVRecordReader implements RecordReader {
                     }
                 }
             }
+
             // If we didn't find a record, then the end of the file was comprised of empty lines, so we have no record to return
             if (!foundRecord) {
                 return null;
             }
 
-            final Map<String, Object> values = new LinkedHashMap<>();
+            final Map<String, Object> values = new HashMap<>(rawFieldNames.size() * 2);
             final int numFieldNames = rawFieldNames.size();
             for (int i = 0; i < csvRecord.length; i++) {
                 final String rawFieldName = numFieldNames <= i ? "unknown_field_index_" + i : rawFieldNames.get(i);

nifi-nar-bundles/nifi-standard-services/nifi-record-serialization-services-bundle/nifi-record-serialization-services/src/main/java/org/apache/nifi/json/JsonTreeRowRecordReader.java

@@ -23,7 +23,6 @@ import java.text.DateFormat;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Iterator;
-import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.function.Supplier;
@@ -84,20 +83,52 @@ public class JsonTreeRowRecordReader extends AbstractJsonRowRecordReader {
         return convertJsonNodeToRecord(jsonNode, schema, fieldNamePrefix, coerceTypes, dropUnknown);
     }
 
+    private JsonNode getChildNode(final JsonNode jsonNode, final RecordField field) {
+        if (jsonNode.has(field.getFieldName())) {
+            return jsonNode.get(field.getFieldName());
+        }
+
+        for (final String alias : field.getAliases()) {
+            if (jsonNode.has(alias)) {
+                return jsonNode.get(alias);
+            }
+        }
+
+        return null;
+    }
 
     private Record convertJsonNodeToRecord(final JsonNode jsonNode, final RecordSchema schema, final String fieldNamePrefix,
             final boolean coerceTypes, final boolean dropUnknown) throws IOException, MalformedRecordException {
 
-        final Map<String, Object> values = new LinkedHashMap<>();
+        final Map<String, Object> values = new HashMap<>(schema.getFieldCount() * 2);
+
+        if (dropUnknown) {
+            for (final RecordField recordField : schema.getFields()) {
+                final JsonNode childNode = getChildNode(jsonNode, recordField);
+                if (childNode == null) {
+                    continue;
+                }
+
+                final String fieldName = recordField.getFieldName();
+
+                final Object value;
+                if (coerceTypes) {
+                    final DataType desiredType = recordField.getDataType();
+                    final String fullFieldName = fieldNamePrefix == null ? fieldName : fieldNamePrefix + fieldName;
+                    value = convertField(childNode, fullFieldName, desiredType, dropUnknown);
+                } else {
+                    value = getRawNodeValue(childNode, recordField == null ? null : recordField.getDataType());
+                }
+
+                values.put(fieldName, value);
+            }
+        } else {
             final Iterator<String> fieldNames = jsonNode.getFieldNames();
             while (fieldNames.hasNext()) {
                 final String fieldName = fieldNames.next();
                 final JsonNode childNode = jsonNode.get(fieldName);
 
                 final RecordField recordField = schema.getField(fieldName).orElse(null);
-            if (recordField == null && dropUnknown) {
-                continue;
-            }
 
                 final Object value;
                 if (coerceTypes && recordField != null) {
@@ -110,6 +141,7 @@ public class JsonTreeRowRecordReader extends AbstractJsonRowRecordReader {
 
                 values.put(fieldName, value);
             }
+        }
 
         final Supplier<String> supplier = () -> jsonNode.toString();
         return new MapRecord(schema, values, SerializedForm.of(supplier, "application/json"), false, dropUnknown);

nifi-nar-bundles/nifi-standard-services/nifi-record-serialization-services-bundle/nifi-record-serialization-services/src/main/java/org/apache/nifi/json/WriteJsonResult.java

@@ -21,6 +21,7 @@ import java.io.IOException;
 import java.io.OutputStream;
 import java.math.BigInteger;
 import java.text.DateFormat;
+import java.util.Collections;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
@@ -117,26 +118,31 @@ public class WriteJsonResult extends AbstractRecordSetWriter implements RecordSe
     public Map<String, String> writeRecord(final Record record) throws IOException {
         // If we are not writing an active record set, then we need to ensure that we write the
         // schema information.
+        boolean firstRecord = false;
         if (!isActiveRecordSet()) {
             generator.flush();
             schemaAccess.writeHeader(recordSchema, getOutputStream());
+            firstRecord = true;
         }
 
         writeRecord(record, recordSchema, generator, g -> g.writeStartObject(), g -> g.writeEndObject(), true);
-        return schemaAccess.getAttributes(recordSchema);
+        return firstRecord ? schemaAccess.getAttributes(recordSchema) : Collections.emptyMap();
     }
 
     @Override
     public WriteResult writeRawRecord(final Record record) throws IOException {
         // If we are not writing an active record set, then we need to ensure that we write the
         // schema information.
+        boolean firstRecord = false;
         if (!isActiveRecordSet()) {
             generator.flush();
             schemaAccess.writeHeader(recordSchema, getOutputStream());
+            firstRecord = true;
         }
 
         writeRecord(record, recordSchema, generator, g -> g.writeStartObject(), g -> g.writeEndObject(), false);
-        return WriteResult.of(incrementRecordCount(), schemaAccess.getAttributes(recordSchema));
+        final Map<String, String> attributes = firstRecord ? schemaAccess.getAttributes(recordSchema) : Collections.emptyMap();
+        return WriteResult.of(incrementRecordCount(), attributes);
     }
 
     private void writeRecord(final Record record, final RecordSchema writeSchema, final JsonGenerator generator,