Java Read类代码示例

import com.google.cloud.dataflow.sdk.io.Read; //导入依赖的package包/类
@Test
public void test_reading() throws Exception {
    final File file =
            new File(getClass().getResource("/sample.csv").toURI());
    assertThat(file.exists()).isTrue();

    final Pipeline pipeline = TestPipeline.create();

    final PCollection<String> output =
            pipeline.apply(Read.from(CsvWithHeaderFileSource.from(file.getAbsolutePath())));

    DataflowAssert
            .that(output)
            .containsInAnyOrder("a:1, b:2, c:3, ", "a:4, b:5, c:6, ");

    pipeline.run();
}
 

import com.google.cloud.dataflow.sdk.io.Read; //导入依赖的package包/类
private PCollection<String> constructPipeline(Pipeline pipeline, String org) {
  // Read projects from the CRM API.
  PCollection<GCPProject> projects =
      pipeline.apply(Read.from(new LiveProjectSource(org)));
  // List the service accounts of the projects.
  PCollection<GCPServiceAccount> serviceAccounts =
      projects.apply(ParDo.named("List Service Accounts").of(new ListServiceAccounts()));
  // List the keys of the service accounts.
  PCollection<GCPServiceAccountKey> serviceAccountKeys =
      serviceAccounts.apply(ParDo.named("List Service Account Keys")
          .of(new ListServiceAccountKeys()));
  // Construct an alert message for all the discrepancies found.
  return serviceAccountKeys.apply(ParDo
      .named("Remove user-managed keys")
      .of(new ExportedServiceAccountKeyMessenger()));
}
 

import com.google.cloud.dataflow.sdk.io.Read; //导入依赖的package包/类
public static void main(String[] args) {
  CloudBigtableOptions options =
      PipelineOptionsFactory.fromArgs(args).withValidation().as(CloudBigtableOptions.class);

  CloudBigtableScanConfiguration config =
      new CloudBigtableScanConfiguration.Builder()
          .withProjectId(options.getBigtableProjectId())
          .withInstanceId(options.getBigtableInstanceId())
          .withTableId(options.getBigtableTableId())
          .build();

  options.setStreaming(true);
  options.setRunner(DataflowPipelineRunner.class);

  Pipeline p = Pipeline.create(options);
  CloudBigtableIO.initializeForWrite(p);

  p.apply(Read.from(new CoinbaseSource()))
      .apply(ParDo.named("DeserializeCoinbase").of(new DeserializeCoinbase()))
      .apply(ParDo.of(new HBaseBigtableWriter()))
      .apply(CloudBigtableIO.writeToTable(config));

  p.run();
}
 

import com.google.cloud.dataflow.sdk.io.Read; //导入依赖的package包/类
private PCollection<String> constructPipeline(Pipeline pipeline, String org,
    BoundedSource<KV<List<String>, String>> knownGoodSource) {
  // Read files from GCS.
  PCollection<KV<List<String>, String>> knownGoodFiles =
      pipeline.apply("Read known-good data", Read.from(knownGoodSource));
  // Convert files to GCPResourceState objects.
  PCollection<KV<GCPResource, GCPResourceState>> knownGoodStates =
      knownGoodFiles.apply(ParDo.named("Convert file data to Java Objects")
          .of(new FileToState()));
  // Tag the state objects to indicate they're from a checked-in repo and not live.
  PCollection<KV<GCPResource, KV<StateSource, GCPResourceState>>> taggedKnownGoodStates =
      knownGoodStates.apply(ParDo.named("Mark states as being known-good")
          .of(new TagStateWithSource(StateSource.DESIRED)));

  // Read projects from the CRM API.
  PCollection<GCPProject> allProjects =
      pipeline.apply("Read live projects", Read.from(new LiveProjectSource(org)));
  // Extract project states.
  PCollection<KV<GCPResource, GCPResourceState>> liveStates =
      allProjects
          .apply(ParDo.named("Extract project policies").of(new ExtractState()));
  // Tag the states to indicate they're live and not from a checked-in source.
  PCollection<KV<GCPResource, KV<StateSource, GCPResourceState>>> taggedLiveStates =
      liveStates.apply(ParDo.named("Mark states as being live")
          .of(new TagStateWithSource(StateSource.LIVE)));

  // Join the two known-good and the live halves.
  PCollectionView<Map<GCPResource, KV<StateSource, GCPResourceState>>> knownGoodStatesView =
      taggedKnownGoodStates.apply(View.<GCPResource, KV<StateSource, GCPResourceState>>asMap());
  PCollection<KV<GCPResource, Map<StateSource, GCPResourceState>>> mismatchedStates =
      taggedLiveStates.apply(ParDo.named("Find states that don't match")
          .withSideInputs(knownGoodStatesView)
          .of(new FilterOutMatchingState(knownGoodStatesView)));

  // Construct an alert message for all the discrepancies found and fix the discrepancies.
  return mismatchedStates
      .apply(ParDo.named("Fix discrepancies").of(discrepancyAutoFixMessenger));
}
 

import com.google.cloud.dataflow.sdk.io.Read; //导入依赖的package包/类
private PCollection<String> constructPipeline(Pipeline pipeline,
    BoundedSource<KV<List<String>, String>> knownGoodSource) {
  // Read files from GCS.
  PCollection<KV<List<String>, String>> knownGoodFiles =
      pipeline.apply("Read known-good data", Read.from(knownGoodSource));
  // Convert files to GCPResourceState objects.
  PCollection<KV<GCPResource, GCPResourceState>> knownGoodStates =
      knownGoodFiles.apply(ParDo.named("Convert file data to Java objects")
          .of(new FileToState()));
  // Tag the state objects to indicate they're from a checked-in repo and not live.
  PCollection<KV<GCPResource, KV<StateSource, GCPResourceState>>> taggedKnownGoodStates =
      knownGoodStates.apply(ParDo.named("Mark states as being known-good")
          .of(new TagStateWithSource(StateSource.DESIRED)));

  // Extract a list of checked-in projects from GCS.
  PCollection<List<String>> allFilePaths = knownGoodFiles
      .apply("Extract just the file paths", ParDo.of(new FilePathFromPair()));
  // Read the live version of the states of the checked-in projects.
  PCollection<KV<GCPResource, GCPResourceState>> liveStates =
      allFilePaths.apply(ParDo.named("Get live resource and states from file path")
          .of(new FilePathToLiveState()));
  // Tag the states to indicate they're live and not from a checked-in source.
  PCollection<KV<GCPResource, KV<StateSource, GCPResourceState>>> taggedLiveStates =
      liveStates.apply(ParDo.named("Mark states as being live")
          .of(new TagStateWithSource(StateSource.LIVE)));

  // Join the two known-good and the live halves.
  PCollectionView<Map<GCPResource, KV<StateSource, GCPResourceState>>> liveStatesView =
      taggedLiveStates.apply(View.<GCPResource, KV<StateSource, GCPResourceState>>asMap());
  PCollection<KV<GCPResource, Map<StateSource, GCPResourceState>>> mismatchedStates =
      taggedKnownGoodStates.apply(ParDo.named("Find states that don't match")
          .withSideInputs(liveStatesView)
          .of(new FilterOutMatchingState(liveStatesView)));
  // Construct an alert message for all the discrepancies found.
  return mismatchedStates.apply(ParDo
      .named("Generate notification messages")
      .of(new StateDiscrepancyMessenger()));
}