juplo.de Git - demos/kafka/demos-kafka-payment-system-transfer/blob - TransferService.java

   1 package de.juplo.kafka.payment.transfer.domain;
   2
   3
   4 import com.fasterxml.jackson.core.JsonProcessingException;
   5 import com.fasterxml.jackson.databind.ObjectMapper;
   6 import lombok.RequiredArgsConstructor;
   7 import lombok.extern.slf4j.Slf4j;
   8 import org.apache.kafka.clients.producer.KafkaProducer;
   9 import org.apache.kafka.clients.producer.ProducerRecord;
  10 import org.springframework.http.ResponseEntity;
  11
  12 import java.net.URI;
  13 import java.util.UUID;
  14
  15 import static de.juplo.kafka.payment.transfer.domain.Transfer.State.*;
  16
  17
  18 @Slf4j
  19 @RequiredArgsConstructor
  20 public class TransferService
  21 {
  22   private final TransferRepository repository;
  23   private final KafkaProducer<String, String> producer;
  24   private final ObjectMapper mapper;
  25   private final String topic;
  26
  27   public synchronized void initiate(Transfer transfer)
  28   {
  29     repository
  30         .get(transfer.getId())
  31         .ifPresentOrElse(
  32             stored ->
  33             {
  34               if (!transfer.equals(stored))
  35                 throw new IllegalArgumentException(
  36                     "Re-Initiation of transfer with different data: old=" +
  37                         stored +
  38                         ", new=" +
  39                         transfer);
  40
  41               if (stored.getState() == FAILED)
  42               {
  43                 repository.update(transfer.getId(), FAILED, SENT);
  44                 log.info("Resending faild transfer: " + stored);
  45                 send(transfer);
  46               }
  47             },
  48             () ->
  49             {
  50               repository.store(transfer);
  51               send(transfer);
  52             });
  53   }
  54
  55
  56   private void send(Transfer transfer)
  57   {
  58     try
  59     {
  60       ProducerRecord<String, String> record =
  61           new ProducerRecord<>(
  62               topic,
  63               Long.toString(transfer.getId()),
  64               mapper.writeValueAsString(transfer));
  65
  66       producer.send(record, (metadata, exception) ->
  67       {
  68         if (metadata != null)
  69         {
  70           log.debug("Sent {} to {}/{}:{}", transfer, metadata.topic(), metadata.partition(), metadata.offset());
  71           repository.update(transfer.getId(), SENT, PENDING);
  72         }
  73         else
  74         {
  75           log.error("Could not send {}: {}", transfer, exception.getMessage());
  76           repository.update(transfer.getId(), SENT, FAILED);
  77         }
  78       });
  79     }
  80     catch (JsonProcessingException e)
  81     {
  82       throw new RuntimeException("Could not convert " + transfer, e);
  83     }
  84   }
  85 }