构建此GCP数据流示例以将Pubsub转换为Bigquery流时出错

Question

I am trying to build the following example of streaming Pub/Sub to BigQuery:

https://github.com/GoogleCloudPlatform/DataflowTemplates/blob/master/src/main/java/com/google/cloud/teleport/templates/PubSubToBigQuery.java

code is:

/*
 * Copyright (C) 2018 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.cloud.teleport.templates;

import static com.google.cloud.teleport.templates.TextToBigQueryStreaming.wrapBigQueryInsertError;

import com.google.api.services.bigquery.model.TableRow;
import com.google.cloud.teleport.coders.FailsafeElementCoder;
import com.google.cloud.teleport.templates.common.BigQueryConverters.FailsafeJsonToTableRow;
import com.google.cloud.teleport.templates.common.ErrorConverters;
import com.google.cloud.teleport.templates.common.JavascriptTextTransformer.FailsafeJavascriptUdf;
import com.google.cloud.teleport.templates.common.JavascriptTextTransformer.JavascriptTextTransformerOptions;
import com.google.cloud.teleport.util.DualInputNestedValueProvider;
import com.google.cloud.teleport.util.DualInputNestedValueProvider.TranslatorInput;
import com.google.cloud.teleport.util.ResourceUtils;
import com.google.cloud.teleport.util.ValueProviderUtils;
import com.google.cloud.teleport.values.FailsafeElement;
import com.google.common.collect.ImmutableList;
import java.nio.charset.StandardCharsets;
import org.apache.beam.sdk.Pipeline;
import org.apache.beam.sdk.PipelineResult;
import org.apache.beam.sdk.coders.CoderRegistry;
import org.apache.beam.sdk.coders.StringUtf8Coder;
import org.apache.beam.sdk.io.gcp.bigquery.BigQueryIO;
import org.apache.beam.sdk.io.gcp.bigquery.BigQueryIO.Write.CreateDisposition;
import org.apache.beam.sdk.io.gcp.bigquery.BigQueryIO.Write.WriteDisposition;
import org.apache.beam.sdk.io.gcp.bigquery.BigQueryInsertError;
import org.apache.beam.sdk.io.gcp.bigquery.InsertRetryPolicy;
import org.apache.beam.sdk.io.gcp.bigquery.WriteResult;
import org.apache.beam.sdk.io.gcp.pubsub.PubsubIO;
import org.apache.beam.sdk.io.gcp.pubsub.PubsubMessage;
import org.apache.beam.sdk.io.gcp.pubsub.PubsubMessageWithAttributesCoder;
import org.apache.beam.sdk.options.Default;
import org.apache.beam.sdk.options.Description;
import org.apache.beam.sdk.options.PipelineOptions;
import org.apache.beam.sdk.options.PipelineOptionsFactory;
import org.apache.beam.sdk.options.ValueProvider;
import org.apache.beam.sdk.transforms.DoFn;
import org.apache.beam.sdk.transforms.Flatten;
import org.apache.beam.sdk.transforms.MapElements;
import org.apache.beam.sdk.transforms.PTransform;
import org.apache.beam.sdk.transforms.ParDo;
import org.apache.beam.sdk.transforms.SerializableFunction;
import org.apache.beam.sdk.values.PCollection;
import org.apache.beam.sdk.values.PCollectionList;
import org.apache.beam.sdk.values.PCollectionTuple;
import org.apache.beam.sdk.values.TupleTag;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * The {@link PubSubToBigQuery} pipeline is a streaming pipeline which ingests data in JSON format
 * from Cloud Pub/Sub, executes a UDF, and outputs the resulting records to BigQuery. Any errors
 * which occur in the transformation of the data or execution of the UDF will be output to a
 * separate errors table in BigQuery. The errors table will be created if it does not exist prior to
 * execution. Both output and error tables are specified by the user as template parameters.
 *
 * <p><b>Pipeline Requirements</b>
 *
 * <ul>
 *   <li>The Pub/Sub topic exists.
 *   <li>The BigQuery output table exists.
 * </ul>
 *
 * <p><b>Example Usage</b>
 *
 * <pre>
 * # Set the pipeline vars
 * PROJECT_ID=PROJECT ID HERE
 * BUCKET_NAME=BUCKET NAME HERE
 * PIPELINE_FOLDER=gs://${BUCKET_NAME}/dataflow/pipelines/pubsub-to-bigquery
 * USE_SUBSCRIPTION=true or false depending on whether the pipeline should read
 *                  from a Pub/Sub Subscription or a Pub/Sub Topic.
 *
 * # Set the runner
 * RUNNER=DataflowRunner
 *
 * # Build the template
 * mvn compile exec:java \
 * -Dexec.mainClass=com.google.cloud.teleport.templates.PubSubToBigQuery \
 * -Dexec.cleanupDaemonThreads=false \
 * -Dexec.args=" \
 * --project=${PROJECT_ID} \
 * --stagingLocation=${PIPELINE_FOLDER}/staging \
 * --tempLocation=${PIPELINE_FOLDER}/temp \
 * --templateLocation=${PIPELINE_FOLDER}/template \
 * --runner=${RUNNER}
 * --useSubscription=${USE_SUBSCRIPTION}
 * "
 *
 * # Execute the template
 * JOB_NAME=pubsub-to-bigquery-$USER-`date +"%Y%m%d-%H%M%S%z"`
 *
 * # Execute a pipeline to read from a Topic.
 * gcloud dataflow jobs run ${JOB_NAME} \
 * --gcs-location=${PIPELINE_FOLDER}/template \
 * --zone=us-east1-d \
 * --parameters \
 * "inputTopic=projects/${PROJECT_ID}/topics/input-topic-name,\
 * outputTableSpec=${PROJECT_ID}:dataset-id.output-table,\
 * outputDeadletterTable=${PROJECT_ID}:dataset-id.deadletter-table"
 *
 * # Execute a pipeline to read from a Subscription.
 * gcloud dataflow jobs run ${JOB_NAME} \
 * --gcs-location=${PIPELINE_FOLDER}/template \
 * --zone=us-east1-d \
 * --parameters \
 * "inputSubscription=projects/${PROJECT_ID}/subscriptions/input-subscription-name,\
 * outputTableSpec=${PROJECT_ID}:dataset-id.output-table,\
 * outputDeadletterTable=${PROJECT_ID}:dataset-id.deadletter-table"
 * </pre>
 */
public class PubSubToBigQuery {

  /** The log to output status messages to. */
  private static final Logger LOG = LoggerFactory.getLogger(PubSubToBigQuery.class);

  /** The tag for the main output for the UDF. */
  public static final TupleTag<FailsafeElement<PubsubMessage, String>> UDF_OUT =
      new TupleTag<FailsafeElement<PubsubMessage, String>>() {};

  /** The tag for the main output of the json transformation. */
  public static final TupleTag<TableRow> TRANSFORM_OUT = new TupleTag<TableRow>() {};

  /** The tag for the dead-letter output of the udf. */
  public static final TupleTag<FailsafeElement<PubsubMessage, String>> UDF_DEADLETTER_OUT =
      new TupleTag<FailsafeElement<PubsubMessage, String>>() {};

  /** The tag for the dead-letter output of the json to table row transform. */
  public static final TupleTag<FailsafeElement<PubsubMessage, String>> TRANSFORM_DEADLETTER_OUT =
      new TupleTag<FailsafeElement<PubsubMessage, String>>() {};

  /** The default suffix for error tables if dead letter table is not specified. */
  public static final String DEFAULT_DEADLETTER_TABLE_SUFFIX = "_error_records";

  /** Pubsub message/string coder for pipeline. */
  public static final FailsafeElementCoder<PubsubMessage, String> CODER =
      FailsafeElementCoder.of(PubsubMessageWithAttributesCoder.of(), StringUtf8Coder.of());

  /** String/String Coder for FailsafeElement. */
  public static final FailsafeElementCoder<String, String> FAILSAFE_ELEMENT_CODER =
      FailsafeElementCoder.of(StringUtf8Coder.of(), StringUtf8Coder.of());

  /**
   * The {@link Options} class provides the custom execution options passed by the executor at the
   * command-line.
   */
  public interface Options extends PipelineOptions, JavascriptTextTransformerOptions {
    @Description("Table spec to write the output to")
    ValueProvider<String> getOutputTableSpec();

    void setOutputTableSpec(ValueProvider<String> value);

    @Description("Pub/Sub topic to read the input from")
    ValueProvider<String> getInputTopic();

    void setInputTopic(ValueProvider<String> value);

    @Description(
        "The Cloud Pub/Sub subscription to consume from. "
            + "The name should be in the format of "
            + "projects/<project-id>/subscriptions/<subscription-name>.")
    ValueProvider<String> getInputSubscription();

    void setInputSubscription(ValueProvider<String> value);

    @Description(
        "This determines whether the template reads from " + "a pub/sub subscription or a topic")
    @Default.Boolean(false)
    Boolean getUseSubscription();

    void setUseSubscription(Boolean value);

    @Description(
        "The dead-letter table to output to within BigQuery in <project-id>:<dataset>.<table> "
            + "format. If it doesn't exist, it will be created during pipeline execution.")
    ValueProvider<String> getOutputDeadletterTable();

    void setOutputDeadletterTable(ValueProvider<String> value);
  }

  /**
   * The main entry-point for pipeline execution. This method will start the pipeline but will not
   * wait for it's execution to finish. If blocking execution is required, use the {@link
   * PubSubToBigQuery#run(Options)} method to start the pipeline and invoke {@code
   * result.waitUntilFinish()} on the {@link PipelineResult}.
   *
   * @param args The command-line args passed by the executor.
   */
  public static void main(String[] args) {
    Options options = PipelineOptionsFactory.fromArgs(args).withValidation().as(Options.class);

    run(options);
  }

  /**
   * Runs the pipeline to completion with the specified options. This method does not wait until the
   * pipeline is finished before returning. Invoke {@code result.waitUntilFinish()} on the result
   * object to block until the pipeline is finished running if blocking programmatic execution is
   * required.
   *
   * @param options The execution options.
   * @return The pipeline result.
   */
  public static PipelineResult run(Options options) {

    Pipeline pipeline = Pipeline.create(options);

    CoderRegistry coderRegistry = pipeline.getCoderRegistry();
    coderRegistry.registerCoderForType(CODER.getEncodedTypeDescriptor(), CODER);

    /*
     * Steps:
     *  1) Read messages in from Pub/Sub
     *  2) Transform the PubsubMessages into TableRows
     *     - Transform message payload via UDF
     *     - Convert UDF result to TableRow objects
     *  3) Write successful records out to BigQuery
     *  4) Write failed records out to BigQuery
     */

    /*
     * Step #1: Read messages in from Pub/Sub
     * Either from a Subscription or Topic
     */

    PCollection<PubsubMessage> messages = null;
    if (options.getUseSubscription()) {
      messages =
          pipeline.apply(
              "ReadPubSubSubscription",
              PubsubIO.readMessagesWithAttributes()
                  .fromSubscription(options.getInputSubscription()));
    } else {
      messages =
          pipeline.apply(
              "ReadPubSubTopic",
              PubsubIO.readMessagesWithAttributes().fromTopic(options.getInputTopic()));
    }

    PCollectionTuple convertedTableRows =
        messages
            /*
             * Step #2: Transform the PubsubMessages into TableRows
             */
            .apply("ConvertMessageToTableRow", new PubsubMessageToTableRow(options));

    /*
     * Step #3: Write the successful records out to BigQuery
     */
    WriteResult writeResult =
        convertedTableRows
            .get(TRANSFORM_OUT)
            .apply(
                "WriteSuccessfulRecords",
                BigQueryIO.writeTableRows()
                    .withoutValidation()
                    .withCreateDisposition(CreateDisposition.CREATE_NEVER)
                    .withWriteDisposition(WriteDisposition.WRITE_APPEND)
                    .withExtendedErrorInfo()
                    .withMethod(BigQueryIO.Write.Method.STREAMING_INSERTS)
                    .withFailedInsertRetryPolicy(InsertRetryPolicy.retryTransientErrors())
                    .to(options.getOutputTableSpec()));

    /*
     * Step 3 Contd.
     * Elements that failed inserts into BigQuery are extracted and converted to FailsafeElement
     */
    PCollection<FailsafeElement<String, String>> failedInserts =
        writeResult
            .getFailedInsertsWithErr()
            .apply(
                "WrapInsertionErrors",
                MapElements.into(FAILSAFE_ELEMENT_CODER.getEncodedTypeDescriptor())
                    .via((BigQueryInsertError e) -> wrapBigQueryInsertError(e)))
            .setCoder(FAILSAFE_ELEMENT_CODER);

    /*
     * Step #4: Write records that failed table row transformation
     * or conversion out to BigQuery deadletter table.
     */
    PCollectionList.of(
            ImmutableList.of(
                convertedTableRows.get(UDF_DEADLETTER_OUT),
                convertedTableRows.get(TRANSFORM_DEADLETTER_OUT)))
        .apply("Flatten", Flatten.pCollections())
        .apply(
            "WriteFailedRecords",
            ErrorConverters.WritePubsubMessageErrors.newBuilder()
                .setErrorRecordsTable(
                    ValueProviderUtils.maybeUseDefaultDeadletterTable(
                        options.getOutputDeadletterTable(),
                        options.getOutputTableSpec(),
                        DEFAULT_DEADLETTER_TABLE_SUFFIX))
                .setErrorRecordsTableSchema(ResourceUtils.getDeadletterTableSchemaJson())
                .build());

    // 5) Insert records that failed insert into deadletter table
    failedInserts.apply(
        "WriteFailedRecords",
        ErrorConverters.WriteStringMessageErrors.newBuilder()
            .setErrorRecordsTable(
                ValueProviderUtils.maybeUseDefaultDeadletterTable(
                    options.getOutputDeadletterTable(),
                    options.getOutputTableSpec(),
                    DEFAULT_DEADLETTER_TABLE_SUFFIX))
            .setErrorRecordsTableSchema(ResourceUtils.getDeadletterTableSchemaJson())
            .build());

    return pipeline.run();
  }

  /**
   * If deadletterTable is available, it is returned as is, otherwise outputTableSpec +
   * defaultDeadLetterTableSuffix is returned instead.
   */
  private static ValueProvider<String> maybeUseDefaultDeadletterTable(
      ValueProvider<String> deadletterTable,
      ValueProvider<String> outputTableSpec,
      String defaultDeadLetterTableSuffix) {
    return DualInputNestedValueProvider.of(
        deadletterTable,
        outputTableSpec,
        new SerializableFunction<TranslatorInput<String, String>, String>() {
          @Override
          public String apply(TranslatorInput<String, String> input) {
            String userProvidedTable = input.getX();
            String outputTableSpec = input.getY();
            if (userProvidedTable == null) {
              return outputTableSpec + defaultDeadLetterTableSuffix;
            }
            return userProvidedTable;
          }
        });
  }

  /**
   * The {@link PubsubMessageToTableRow} class is a {@link PTransform} which transforms incoming
   * {@link PubsubMessage} objects into {@link TableRow} objects for insertion into BigQuery while
   * applying an optional UDF to the input. The executions of the UDF and transformation to {@link
   * TableRow} objects is done in a fail-safe way by wrapping the element with it's original payload
   * inside the {@link FailsafeElement} class. The {@link PubsubMessageToTableRow} transform will
   * output a {@link PCollectionTuple} which contains all output and dead-letter {@link
   * PCollection}.
   *
   * <p>The {@link PCollectionTuple} output will contain the following {@link PCollection}:
   *
   * <ul>
   *   <li>{@link PubSubToBigQuery#UDF_OUT} - Contains all {@link FailsafeElement} records
   *       successfully processed by the optional UDF.
   *   <li>{@link PubSubToBigQuery#UDF_DEADLETTER_OUT} - Contains all {@link FailsafeElement}
   *       records which failed processing during the UDF execution.
   *   <li>{@link PubSubToBigQuery#TRANSFORM_OUT} - Contains all records successfully converted from
   *       JSON to {@link TableRow} objects.
   *   <li>{@link PubSubToBigQuery#TRANSFORM_DEADLETTER_OUT} - Contains all {@link FailsafeElement}
   *       records which couldn't be converted to table rows.
   * </ul>
   */
  static class PubsubMessageToTableRow
      extends PTransform<PCollection<PubsubMessage>, PCollectionTuple> {

    private final Options options;

    PubsubMessageToTableRow(Options options) {
      this.options = options;
    }

    @Override
    public PCollectionTuple expand(PCollection<PubsubMessage> input) {

      PCollectionTuple udfOut =
          input
              // Map the incoming messages into FailsafeElements so we can recover from failures
              // across multiple transforms.
              .apply("MapToRecord", ParDo.of(new PubsubMessageToFailsafeElementFn()))
              .apply(
                  "InvokeUDF",
                  FailsafeJavascriptUdf.<PubsubMessage>newBuilder()
                      .setFileSystemPath(options.getJavascriptTextTransformGcsPath())
                      .setFunctionName(options.getJavascriptTextTransformFunctionName())
                      .setSuccessTag(UDF_OUT)
                      .setFailureTag(UDF_DEADLETTER_OUT)
                      .build());

      // Convert the records which were successfully processed by the UDF into TableRow objects.
      PCollectionTuple jsonToTableRowOut =
          udfOut
              .get(UDF_OUT)
              .apply(
                  "JsonToTableRow",
                  FailsafeJsonToTableRow.<PubsubMessage>newBuilder()
                      .setSuccessTag(TRANSFORM_OUT)
                      .setFailureTag(TRANSFORM_DEADLETTER_OUT)
                      .build());

      // Re-wrap the PCollections so we can return a single PCollectionTuple
      return PCollectionTuple.of(UDF_OUT, udfOut.get(UDF_OUT))
          .and(UDF_DEADLETTER_OUT, udfOut.get(UDF_DEADLETTER_OUT))
          .and(TRANSFORM_OUT, jsonToTableRowOut.get(TRANSFORM_OUT))
          .and(TRANSFORM_DEADLETTER_OUT, jsonToTableRowOut.get(TRANSFORM_DEADLETTER_OUT));
    }
  }

  /**
   * The {@link PubsubMessageToFailsafeElementFn} wraps an incoming {@link PubsubMessage} with the
   * {@link FailsafeElement} class so errors can be recovered from and the original message can be
   * output to a error records table.
   */
  static class PubsubMessageToFailsafeElementFn
      extends DoFn<PubsubMessage, FailsafeElement<PubsubMessage, String>> {
    @ProcessElement
    public void processElement(ProcessContext context) {
      PubsubMessage message = context.element();
      context.output(
          FailsafeElement.of(message, new String(message.getPayload(), StandardCharsets.UTF_8)));
    }
  }
}

using the following maven

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>pubsub_bigquery_dataflow</groupId>
  <artifactId>pubsub_bigquery_dataflow</artifactId>
  <version>1.0-SNAPSHOT</version>

  <name>pubsub_bigquery_dataflow</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.7</maven.compiler.source>
    <maven.compiler.target>1.7</maven.compiler.target>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>com.google.cloud.dataflow</groupId>
      <artifactId>google-cloud-dataflow-java-sdk-all</artifactId>
      <version>2.5.0</version>
    </dependency>
  </dependencies>

  <build>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
      <plugins>
        <!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.1.0</version>
        </plugin>
        <!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-jar-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
        <!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
        <plugin>
          <artifactId>maven-site-plugin</artifactId>
          <version>3.7.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-project-info-reports-plugin</artifactId>
          <version>3.0.0</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

But I get errors like the package "com.google.cloud.teleport.coders" does not exist. The example also appears at https://cloud.google.com/dataflow/docs/guides/templates/provided-templates#cloudpubsubtobigquery but with not instructions about which JARs are needed, or any dependencies file.

Answer 1

The class you are trying to build can't be built with just that file. It references several other classes that appear in the repository itself, eg, com.google.cloud.teleport.coders . The main instructions for the repo say that one must build the entire project with the command mvn clean compile . The instructions then provide the command needed to build and stage a template file. If you are going to pull one of the templates out in isolation, you will need to include the external dependencies in the pom file and also extract the local dependencies that they are built. The import statements should indicate the dependencies. Those within com.google.cloud.teleport are all in this same repo . The rest would be referenced in the main pom.xml .

Answer 2

从DataflowTemplates Github中检查pom.xml ，似乎是您缺少一些依赖项。