我知道在创建侧输出之前我们必须创建TupleTag。但是，如果我事先不知道必须创建多少侧输出，该怎么办呢？
我需要根据Apache Beam中的一列数据创建侧输出。有没有办法实现这个目标？
动态目的地代码：
readTableRow.apply("Write output to BigQuery",BigQueryIO.writeTableRows()
.to(new DynamicDestinations<TableRow, String>() {
private static final long serialVersionUID = 1L;
@Override
public List<PCollectionView<?>> getSideInputs() {
return ImmutableList.of(distinctDatesView);
}
@Override
public String getDestination(ValueInSingleWindow<TableRow> element) {
List<String> list = sideInput(distinctDatesView);
LOG.info("Element: "+element);
String tableSpec = "project-id:dataset-id.table-id";
for(String str:list)
{
if(element.getValue().get("date").equals(str))
{
tableSpec = "project-id:dataset-id.table-id$"+str;
return tableSpec;
}
}
return tableSpec;
}
@Override
public TableSchema getSchema(String arg0) {
List<TableFieldSchema> fields = new ArrayList<>();
fields.add(new TableFieldSchema().setName("letter").setType("STRING"));
fields.add(new TableFieldSchema().setName("date").setType("STRING"));
TableSchema schema = new TableSchema().setFields(fields);
return schema;
}
@Override
public TableDestination getTable(String arg1) {
LOG.info("destination: "+arg1); //arg1 = PROJECT:DATASET.MYTABLE$20171102
String tableSpec = arg1;
TableReference reference = new TableReference();
return new TableDestination(tableSpec, "");
}
})
.withCreateDisposition(BigQueryIO.Write.CreateDisposition.CREATE_NEVER)
.withWriteDisposition(BigQueryIO.Write.WriteDisposition.WRITE_TRUNCATE).withoutValidation());
我收到的错误：
(5bd903d2a90b859e): java.lang.RuntimeException: org.apache.beam.sdk.util.UserCodeException: java.io.IOException: Unable to patch table description: {datasetId=myDATASET, projectId=myPROJECT, tableId=myTABLE$20171105}, aborting after 9 retries.
at com.google.cloud.dataflow.worker.GroupAlsoByWindowsParDoFn$1.output(GroupAlsoByWindowsParDoFn.java:182)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowFnRunner$1.outputWindowedValue(GroupAlsoByWindowFnRunner.java:104)
at com.google.cloud.dataflow.worker.util.BatchGroupAlsoByWindowReshuffleFn.processElement(BatchGroupAlsoByWindowReshuffleFn.java:54)
at com.google.cloud.dataflow.worker.util.BatchGroupAlsoByWindowReshuffleFn.processElement(BatchGroupAlsoByWindowReshuffleFn.java:37)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowFnRunner.invokeProcessElement(GroupAlsoByWindowFnRunner.java:117)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowFnRunner.processElement(GroupAlsoByWindowFnRunner.java:74)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowsParDoFn.processElement(GroupAlsoByWindowsParDoFn.java:113)
at com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
at com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
at com.google.cloud.dataflow.worker.util.common.worker.ReadOperation.runReadLoop(ReadOperation.java:187)
at com.google.cloud.dataflow.worker.util.common.worker.ReadOperation.start(ReadOperation.java:148)
at com.google.cloud.dataflow.worker.util.common.worker.MapTaskExecutor.execute(MapTaskExecutor.java:68)
at com.google.cloud.dataflow.worker.DataflowWorker.executeWork(DataflowWorker.java:330)
at com.google.cloud.dataflow.worker.DataflowWorker.doWork(DataflowWorker.java:302)
at com.google.cloud.dataflow.worker.DataflowWorker.getAndPerformWork(DataflowWorker.java:251)
at com.google.cloud.dataflow.worker.DataflowBatchWorkerHarness$WorkerThread.doWork(DataflowBatchWorkerHarness.java:135)
at com.google.cloud.dataflow.worker.DataflowBatchWorkerHarness$WorkerThread.call(DataflowBatchWorkerHarness.java:115)
at com.google.cloud.dataflow.worker.DataflowBatchWorkerHarness$WorkerThread.call(DataflowBatchWorkerHarness.java:102)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.beam.sdk.util.UserCodeException: java.io.IOException: Unable to patch table description: {datasetId=myDATASET, projectId=myPROJECT, tableId=myTABLE$20171105}, aborting after 9 retries.
at org.apache.beam.sdk.util.UserCodeException.wrap(UserCodeException.java:36)
at org.apache.beam.sdk.io.gcp.bigquery.WriteTables$WriteTablesDoFn$DoFnInvoker.invokeProcessElement(Unknown Source)
at org.apache.beam.runners.core.SimpleDoFnRunner.invokeProcessElement(SimpleDoFnRunner.java:177)
at org.apache.beam.runners.core.SimpleDoFnRunner.processElement(SimpleDoFnRunner.java:138)
at com.google.cloud.dataflow.worker.SimpleParDoFn.processElement(SimpleParDoFn.java:324)
at com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
at com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
at com.google.cloud.dataflow.worker.SimpleParDoFn$1.output(SimpleParDoFn.java:272)
at org.apache.beam.runners.core.SimpleDoFnRunner.outputWindowedValue(SimpleDoFnRunner.java:211)
at org.apache.beam.runners.core.SimpleDoFnRunner.access$700(SimpleDoFnRunner.java:66)
at org.apache.beam.runners.core.SimpleDoFnRunner$DoFnProcessContext.output(SimpleDoFnRunner.java:436)
at org.apache.beam.runners.core.SimpleDoFnRunner$DoFnProcessContext.output(SimpleDoFnRunner.java:424)
at org.apache.beam.runners.dataflow.ReshuffleOverrideFactory$ReshuffleWithOnlyTrigger$1.processElement(ReshuffleOverrideFactory.java:84)
at org.apache.beam.runners.dataflow.ReshuffleOverrideFactory$ReshuffleWithOnlyTrigger$1$DoFnInvoker.invokeProcessElement(Unknown Source)
at org.apache.beam.runners.core.SimpleDoFnRunner.invokeProcessElement(SimpleDoFnRunner.java:177)
at org.apache.beam.runners.core.SimpleDoFnRunner.processElement(SimpleDoFnRunner.java:141)
at com.google.cloud.dataflow.worker.SimpleParDoFn.processElement(SimpleParDoFn.java:324)
at com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
at com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowsParDoFn$1.output(GroupAlsoByWindowsParDoFn.java:180)
... 21 more
Caused by: java.io.IOException: Unable to patch table description: {datasetId=myDATASET, projectId=myPROJECT, tableId=myTABLE$20171105}, aborting after 9 retries.
at org.apache.beam.sdk.io.gcp.bigquery.BigQueryServicesImpl.executeWithRetries(BigQueryServicesImpl.java:879)
at org.apache.beam.sdk.io.gcp.bigquery.BigQueryServicesImpl$DatasetServiceImpl.patchTableDescription(BigQueryServicesImpl.java:826)
at org.apache.beam.sdk.io.gcp.bigquery.WriteTables.load(WriteTables.java:250)
at org.apache.beam.sdk.io.gcp.bigquery.WriteTables.access$600(WriteTables.java:77)
at org.apache.beam.sdk.io.gcp.bigquery.WriteTables$WriteTablesDoFn.processElement(WriteTables.java:141)
Caused by: com.google.api.client.googleapis.json.GoogleJsonResponseException: 400 Bad Request
{
"code" : 400,
"errors" : [ {
"domain" : "global",
"message" : "Invalid table ID \"myTABLE$20171105\". Table IDs must be alphanumeric (plus underscores) and must be at most 1024 characters long. Also, Table decorators cannot be used.",
"reason" : "invalid"
} ],
"message" : "Invalid table ID \"myTABLE$20171105\". Table IDs must be alphanumeric (plus underscores) and must be at most 1024 characters long. Also, Table decorators cannot be used."
}
at com.google.api.client.googleapis.json.GoogleJsonResponseException.from(GoogleJsonResponseException.java:146)
at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:113)
at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:40)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest$1.interceptResponse(AbstractGoogleClientRequest.java:321)
at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:1065)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:419)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:352)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.execute(AbstractGoogleClientRequest.java:469)
at org.apache.beam.sdk.io.gcp.bigquery.BigQueryServicesImpl.executeWithRetries(BigQueryServicesImpl.java:870)
at org.apache.beam.sdk.io.gcp.bigquery.BigQueryServicesImpl$DatasetServiceImpl.patchTableDescription(BigQueryServicesImpl.java:826)
at org.apache.beam.sdk.io.gcp.bigquery.WriteTables.load(WriteTables.java:250)
at org.apache.beam.sdk.io.gcp.bigquery.WriteTables.access$600(WriteTables.java:77)
at org.apache.beam.sdk.io.gcp.bigquery.WriteTables$WriteTablesDoFn.processElement(WriteTables.java:141)
at org.apache.beam.sdk.io.gcp.bigquery.WriteTables$WriteTablesDoFn$DoFnInvoker.invokeProcessElement(Unknown Source)
at org.apache.beam.runners.core.SimpleDoFnRunner.invokeProcessElement(SimpleDoFnRunner.java:177)
at org.apache.beam.runners.core.SimpleDoFnRunner.processElement(SimpleDoFnRunner.java:138)
at com.google.cloud.dataflow.worker.SimpleParDoFn.processElement(SimpleParDoFn.java:324)
at com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
at com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
at com.google.cloud.dataflow.worker.SimpleParDoFn$1.output(SimpleParDoFn.java:272)
at org.apache.beam.runners.core.SimpleDoFnRunner.outputWindowedValue(SimpleDoFnRunner.java:211)
at org.apache.beam.runners.core.SimpleDoFnRunner.access$700(SimpleDoFnRunner.java:66)
at org.apache.beam.runners.core.SimpleDoFnRunner$DoFnProcessContext.output(SimpleDoFnRunner.java:436)
at org.apache.beam.runners.core.SimpleDoFnRunner$DoFnProcessContext.output(SimpleDoFnRunner.java:424)
at org.apache.beam.runners.dataflow.ReshuffleOverrideFactory$ReshuffleWithOnlyTrigger$1.processElement(ReshuffleOverrideFactory.java:84)
at org.apache.beam.runners.dataflow.ReshuffleOverrideFactory$ReshuffleWithOnlyTrigger$1$DoFnInvoker.invokeProcessElement(Unknown Source)
at org.apache.beam.runners.core.SimpleDoFnRunner.invokeProcessElement(SimpleDoFnRunner.java:177)
at org.apache.beam.runners.core.SimpleDoFnRunner.processElement(SimpleDoFnRunner.java:141)
at com.google.cloud.dataflow.worker.SimpleParDoFn.processElement(SimpleParDoFn.java:324)
at com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
at com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowsParDoFn$1.output(GroupAlsoByWindowsParDoFn.java:180)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowFnRunner$1.outputWindowedValue(GroupAlsoByWindowFnRunner.java:104)
at com.google.cloud.dataflow.worker.util.BatchGroupAlsoByWindowReshuffleFn.processElement(BatchGroupAlsoByWindowReshuffleFn.java:54)
at com.google.cloud.dataflow.worker.util.BatchGroupAlsoByWindowReshuffleFn.processElement(BatchGroupAlsoByWindowReshuffleFn.java:37)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowFnRunner.invokeProcessElement(GroupAlsoByWindowFnRunner.java:117)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowFnRunner.processElement(GroupAlsoByWindowFnRunner.java:74)
at com.google.cloud.dataflow.worker.GroupAlsoByWindowsParDoFn.processElement(GroupAlsoByWindowsParDoFn.java:113)
at com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
at com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
at com.google.cloud.dataflow.worker.util.common.worker.ReadOperation.runReadLoop(ReadOperation.java:187)
at com.google.cloud.dataflow.worker.util.common.worker.ReadOperation.start(ReadOperation.java:148)
at com.google.cloud.dataflow.worker.util.common.worker.MapTaskExecutor.execute(MapTaskExecutor.java:68)
at com.google.cloud.dataflow.worker.DataflowWorker.executeWork(DataflowWorker.java:330)
at com.google.cloud.dataflow.worker.DataflowWorker.doWork(DataflowWorker.java:302)
at com.google.cloud.dataflow.worker.DataflowWorker.getAndPerformWork(DataflowWorker.java:251)
at com.google.cloud.dataflow.worker.DataflowBatchWorkerHarness$WorkerThread.doWork(DataflowBatchWorkerHarness.java:135)
at com.google.cloud.dataflow.worker.DataflowBatchWorkerHarness$WorkerThread.call(DataflowBatchWorkerHarness.java:115)
at com.google.cloud.dataflow.worker.DataflowBatchWorkerHarness$WorkerThread.call(DataflowBatchWorkerHarness.java:102)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
感谢。