juplo.de Git - demos/microservices/blob - take-order/src/main/java/de/trion/microservices/takeorder/TakeOrderService.java

   1 package de.trion.microservices.takeorder;
   2
   3
   4 import de.trion.microservices.avro.Order;
   5 import de.trion.microservices.avro.OrderState;
   6 import java.net.URI;
   7 import java.util.UUID;
   8 import javax.validation.Valid;
   9 import org.apache.kafka.clients.producer.KafkaProducer;
  10 import org.apache.kafka.clients.producer.ProducerRecord;
  11 import org.slf4j.Logger;
  12 import org.slf4j.LoggerFactory;
  13 import org.springframework.http.MediaType;
  14 import org.springframework.http.ResponseEntity;
  15 import org.springframework.web.bind.annotation.PostMapping;
  16 import org.springframework.web.bind.annotation.RequestBody;
  17 import org.springframework.web.bind.annotation.RestController;
  18 import org.springframework.web.context.request.async.DeferredResult;
  19
  20
  21 @RestController
  22 public class TakeOrderService
  23 {
  24   private final static Logger LOG = LoggerFactory.getLogger(TakeOrderService.class);
  25
  26   private final KafkaProducer<UUID,Order> producer;
  27   private final String topic;
  28   private final String path;
  29
  30
  31   TakeOrderService(
  32       final KafkaProducer<UUID,Order> producer,
  33       final ApplicationProperties properties)
  34   {
  35     this.producer = producer;
  36     this.topic = properties.getTopic();
  37     this.path = properties.getPath();
  38   }
  39
  40
  41   @PostMapping(
  42       path = "/orders",
  43       consumes = MediaType.APPLICATION_JSON_UTF8_VALUE,
  44       produces = MediaType.TEXT_PLAIN_VALUE)
  45   public DeferredResult<ResponseEntity<?>> placeOrder(@Valid @RequestBody OrderBean order)
  46   {
  47     DeferredResult<ResponseEntity<?>> result = new DeferredResult<>();
  48
  49     try
  50     {
  51       UUID uuid = UUID.randomUUID();
  52       ProducerRecord<UUID, Order> record =
  53           new ProducerRecord<>(
  54               topic,
  55               uuid,
  56               Order
  57                   .newBuilder()
  58                   .setId(uuid.toString())
  59                   .setState(OrderState.CREATED)
  60                   .setCustomerId(order.getCustomerId())
  61                   .setOrderId(order.getId())
  62                   .setProductId(order.getProductId())
  63                   .setQuantity(order.getQuantity())
  64                   .build());
  65
  66       producer.send(record, (metadata, exception) ->
  67       {
  68         if (exception != null)
  69         {
  70           LOG.error("Could not place order {}: {}", order, exception.toString());
  71           result.setErrorResult(exception);
  72           return;
  73         }
  74
  75         result.setResult(ResponseEntity.created(URI.create(path + uuid)).build());
  76       });
  77     }
  78     catch (Exception e)
  79     {
  80       LOG.error("Unexpected exception!", e);
  81       result.setErrorResult(e);
  82     }
  83
  84     return result;
  85   }
  86 }