Problem Mapping Long fields

[claudio-au]

When It is mapped a Long (Not primitive) field on model class and we use pivot function to return the values for each field on model, a Cast exception is thrown during the execution.

It says is not possible cast Long to Double.
When we use long (primitive) it doesn't throw error, however it returns zero (not behavior expected).

Steps to reproduce:

1. Create a model with 2 fields:

ModelInflux.java

//use lombok

@Getter
@Setter
@Measurement(name="model2")
@ToString
public class ModelInflux {

   @Column
  private Long field1;
  @Column
  private Double field2;

  @Column(timestamp = true, name = "time")
  private Instant timestamp;

}

2. Save some data on InfluxDB
   Main.java

  public static void save(ModelInflux object, InfluxDBClientReactive client) {
    WriteReactiveApi writeApi = client.getWriteReactiveApi();

    var publisher = writeApi.writeMeasurement(WritePrecision.NS, object);
    Disposable subscriber =
        Flowable.fromPublisher(publisher)
            .subscribe(success -> log.info("Successfully written ModelInflux measurement"));
    subscriber.dispose();
  }

3. Create a query with pivot function:

private static void runModelInflux(String host, String org, String token, String bucket)
      throws InterruptedException {

    String query = "from(bucket: \"test2\")"
        + "  |> range(start: -1h, stop: now())"
        + "  |> filter(fn: (r) => r[\"_measurement\"] == \"model2\")"
        + "  |> aggregateWindow(every: 10s, fn: mean, createEmpty: false)"
        + "  |> yield(name: \"mean\")"
        + "  |> pivot(rowKey:[\"_time\"], columnKey: [\"_field\"], valueColumn: \"_value\")";

    InfluxDBClientReactive client = InfluxDBClientReactiveFactory
        .create(host, token.toCharArray(), org, bucket);

    ModelInflux modelInflux = new ModelInflux();
    modelInflux.setField1((long)(Math.random() * 100));
    modelInflux.setField2((Math.random() * 100));

    save(modelInflux, client);

    Thread.sleep(1000);

    Instant end = Instant.now();
    Instant start = Instant.now().minus(1, ChronoUnit.HOURS);

    execute(query, client).doOnEach( e -> {
      if (e.get() != null) {
        log.info(e.get().toString());
      }
    }).doOnError(e -> {
      log.error(e.getMessage());
    }).subscribe();

    // Giving a time to process the result.
    Thread.sleep(10000);
  }

Main.java

  public static void main(String[] args) throws InterruptedException {
    String host = Main.HOST;
    String org = Main.ORG;
    String token= Main.TOKEN;
    String bucket = Main.BUCKET;

    runModelInflux2(host, org, token, "test2");
  }

Expected Behavior:

Return the model without error and value available.

Actual Behavior:
Error:
Caused by: com.influxdb.exceptions.InfluxException: Can not set java.lang.Long field com.autonomic.test.domain.ModelInflux2.field1 to java.lang.Double

Specifications:

• Client Version: 6.4.0
• InfluxDB Version: 2.0.9
• JDK Version: Corretto 11.0.15.9.1
• Platform: Mac OS M1

PS.: I see this code is converting only to primitives. (Maybe include more options to conversion?)

influxdb-client-java/client-core/src/main/java/com/influxdb/query/internal/FluxResultMapper.java

Lines 132 to 144 in f9f6aa0

	if (double.class.isAssignableFrom(fieldType)) {
	field.setDouble(object, toDoubleValue(value));
	return;
	}
	if (long.class.isAssignableFrom(fieldType)) {
	field.setLong(object, toLongValue(value));
	return;
	}
	if (int.class.isAssignableFrom(fieldType)) {
	field.setInt(object, toIntValue(value));
	return;
	}
	if (boolean.class.isAssignableFrom(fieldType)) {

[bednar]

Hi @claudio-au,

thanks for using our client.

Your issue is caused by using aggregateWindow function in your query. This function transform a type of the _value to the long due the mean calculation.

Try to use your query without aggregateWindow.

PS.: I see this code is converting only to primitives. (Maybe include more options to conversion?)

It will be good improvement... Is this something you might be willing to help with?

Regards

[claudio-au]

Alright @bednar , thanks for checking it.
Unfortunately, the documentation for the Influxdb is not clear what kind of return is for each function.
I'll modify it on my application.
I'll try to work on this improvement as well

Do you want I close this issue?
Thanks

[bednar]

I've prepared the fix in #414... so we can keep this issue opened until acceptance the PR