content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.camel.component.debezium;
  
  import java.util.Map;
  import java.util.concurrent.ExecutorService;
  
  import io.debezium.data.Envelope;
  import io.debezium.relational.history.HistoryRecord;
  import org.apache.camel.Consumer;
  import org.apache.camel.Exchange;
  import org.apache.camel.Message;
  import org.apache.camel.Processor;
  import org.apache.camel.Producer;
  import org.apache.camel.component.debezium.configuration.EmbeddedDebeziumConfiguration;
  import org.apache.camel.support.DefaultEndpoint;
  import org.apache.kafka.connect.data.Schema;
  import org.apache.kafka.connect.data.Struct;
  import org.apache.kafka.connect.errors.DataException;
  import org.apache.kafka.connect.source.SourceRecord;
  
  /**
   * Base class for debezium endpoint implementation
   */
  public abstract class DebeziumEndpoint<C extends EmbeddedDebeziumConfiguration> extends DefaultEndpoint {
  
      protected DebeziumEndpoint(String uri, DebeziumComponent<C> component) {
          super(uri, component);
      }
  
      protected DebeziumEndpoint() {
      }
  
      @Override
      public Producer createProducer() throws Exception {
          throw new UnsupportedOperationException(
                  "Cannot produce from a DebeziumEndpoint: "
                                                  + getEndpointUri());
      }
  
      @Override
      public Consumer createConsumer(Processor processor) throws Exception {
          DebeziumConsumer consumer = new DebeziumConsumer(this, processor);
          configureConsumer(consumer);
          return consumer;
      }
  
      public ExecutorService createExecutor(Object source) {
          return getCamelContext().getExecutorServiceManager().newSingleThreadExecutor(source,
                  "DebeziumConsumer");
      }
  
      public Exchange createDbzExchange(DebeziumConsumer consumer, final SourceRecord sourceRecord) {
          final Exchange exchange;
          if (consumer != null) {
              exchange = consumer.createExchange(false);
          } else {
              exchange = super.createExchange();
          }
  
          final Message message = exchange.getIn();
  
          final Schema valueSchema = sourceRecord.valueSchema();
          final Object value = sourceRecord.value();
  
          // extract values from SourceRecord
          final Map<String, Object> sourceMetadata = extractSourceMetadataValueFromValueStruct(valueSchema, value);
          final Object operation = extractValueFromValueStruct(valueSchema, value, Envelope.FieldName.OPERATION);
          final Object before = extractValueFromValueStruct(valueSchema, value, Envelope.FieldName.BEFORE);
          final Object body = extractBodyValueFromValueStruct(valueSchema, value);
          final Object timestamp = extractValueFromValueStruct(valueSchema, value, Envelope.FieldName.TIMESTAMP);
          final Object ddl = extractValueFromValueStruct(valueSchema, value, HistoryRecord.Fields.DDL_STATEMENTS);
          // set message headers
          message.setHeader(DebeziumConstants.HEADER_IDENTIFIER, sourceRecord.topic());
          message.setHeader(DebeziumConstants.HEADER_KEY, sourceRecord.key());
          message.setHeader(DebeziumConstants.HEADER_SOURCE_METADATA, sourceMetadata);
          message.setHeader(DebeziumConstants.HEADER_OPERATION, operation);
          message.setHeader(DebeziumConstants.HEADER_BEFORE, before);
          message.setHeader(DebeziumConstants.HEADER_TIMESTAMP, timestamp);
          message.setHeader(DebeziumConstants.HEADER_DDL_SQL, ddl);
          message.setHeader(Exchange.MESSAGE_TIMESTAMP, timestamp);
  
          message.setBody(body);
  
          return exchange;
      }
  
      public abstract C getConfiguration();
  
      public abstract void setConfiguration(C configuration);
  
      protected Object extractBodyValueFromValueStruct(final Schema schema, final Object value) {
          // by default, we will extract the value from field `after`, however if other connector needs different field, this method needs to be overriden
          return extractFieldValueFromValueStruct(schema, value, Envelope.FieldName.AFTER);
      }
  
      protected Object extractFieldValueFromValueStruct(final Schema schema, final Object value, final String fieldName) {
          // first we try with normal extraction from value struct
          final Object valueExtracted = extractValueFromValueStruct(schema, value, fieldName);
  
          if (valueExtracted == null && !isSchemaAStructSchema(schema)) { // we could have anything other than struct, we just return that
              return value;
          }
          return valueExtracted;
      }
  
      private Map<String, Object> extractSourceMetadataValueFromValueStruct(final Schema schema, final Object value) {
          // we want to convert metadata to map since it facilitate usage and also struct structure is not needed for the metadata
          final Object valueExtracted = extractValueFromValueStruct(schema, value, Envelope.FieldName.SOURCE);
  
          if (valueExtracted != null) {
              return DebeziumTypeConverter.toMap((Struct) valueExtracted);
          }
          return null;
      }
  
      private Object extractValueFromValueStruct(final Schema schema, final Object value, final String fieldName) {
          // first we check if we have a value and a schema of struct type
          if (isSchemaAStructSchema(schema) && value != null) {
              // now we return our desired fieldName
              try {
                  final Struct valueStruct = (Struct) value;
                  return valueStruct.get(fieldName);
              } catch (DataException e) {
                  // we return null instead since this exception thrown when no value set or field doesn't exist
                  return null;
              }
          }
          return null;
      }
  
      private boolean isSchemaAStructSchema(final Schema schema) {
          return schema != null && schema.type().equals(Schema.Type.STRUCT);
      }
  }
  