同步 S3 Bucket 并监听变化

Question

我有一个 AWS S3 存储桶，我每周都会在其中放置一个新的 ZIP 文件。

我想向我现有的 Web 服务添加功能，使用 Spring 引导编写：在本地同步存储桶并观察更改。

目前，同步效果很好：无论何时将新文件添加到存储桶中，它都会在本地下载。但是，我不知道要监听文件更新，这是一种在本地下载新文件时触发的方法。可以吗？

这是我的代码片段：

#  --------
# | AWS S3 |
#  --------
s3.credentials-access-key=***
s3.credentials-secret-key=****
s3.bucket = my-bucket
s3.remote-dir = zips
s3.local-dir = D:/s3-bucket/

@Log4j2
@Configuration
public class S3Config {

    public static final String OUT_CHANNEL_NAME = "s3filesChannel";

    @Value("${s3.credentials-access-key}") private String accessKey;
    @Value("${s3.credentials-secret-key}") private String secretKey;
    @Value("${s3.remote-dir}") private String remoteDir;
    @Value("${s3.bucket}") private String s3bucket;
    @Value("${s3.local-dir}") private String localDir;

    /*
     * AWS S3
     */
    @Bean
    public AmazonS3 getAmazonS3(

    ){
        BasicAWSCredentials creds = new BasicAWSCredentials(accessKey, secretKey);
        AmazonS3 s3client = AmazonS3ClientBuilder
                .standard()
                .withRegion(Regions.EU_WEST_1)
                .withCredentials(new AWSStaticCredentialsProvider(creds))
                .build();
        return s3client;        
    }

    @Bean
    public S3SessionFactory s3SessionFactory(AmazonS3 pAmazonS3) {
        return new S3SessionFactory(pAmazonS3);
    }

    @Bean
    public S3InboundFileSynchronizer s3InboundFileSynchronizer(S3SessionFactory pS3SessionFactory) {
        S3InboundFileSynchronizer sync = new S3InboundFileSynchronizer(pS3SessionFactory);
        sync.setPreserveTimestamp(true);
        sync.setDeleteRemoteFiles(false);
        String fullRemotePath = s3bucket.concat("/").concat(remoteDir);
        sync.setRemoteDirectory(fullRemotePath);
        sync.setFilter(new S3RegexPatternFileListFilter(".*\.zip$"));
        return sync;
    }

    @Bean
    @InboundChannelAdapter(value = OUT_CHANNEL_NAME, poller = @Poller(fixedDelay = "30"))
    public S3InboundFileSynchronizingMessageSource s3InboundFileSynchronizingMessageSource(
        S3InboundFileSynchronizer pS3InboundFileSynchronizer
    ) {
        S3InboundFileSynchronizingMessageSource messageSource = new S3InboundFileSynchronizingMessageSource(pS3InboundFileSynchronizer);
        messageSource.setAutoCreateLocalDirectory(true);
        messageSource.setLocalDirectory(new File(localDir));
        messageSource.setLocalFilter(new AcceptOnceFileListFilter<File>());
        return messageSource;
    }

    @Bean("s3filesChannel")
    public PollableChannel s3FilesChannel() {
        return new QueueChannel();
    }

    @Bean
    public IntegrationFlow fileReadingFlow(
            S3InboundFileSynchronizingMessageSource pS3InboundFileSynchronizingMessageSource,
            GtfsBizkaibus pGtfsBizkaibus,
            @Qualifier("fileProcessor") MessageHandler pMessageHandler) {
        return IntegrationFlows
                .from(pS3InboundFileSynchronizingMessageSource, e -> e.poller(p -> p.fixedDelay(5, TimeUnit.SECONDS)))
                .handle(pMessageHandler)
                .get();
    }

    @Bean("fileProcessor")
    public MessageHandler fileProcessor() {
        FileWritingMessageHandler handler = new FileWritingMessageHandler(new File(localDir));
        handler.setExpectReply(false); // end of pipeline, reply not needed
        handler.setFileExistsMode(FileExistsMode.APPEND);
        handler.setNewFileCallback((file, msg) -> {
            log.debug("New file created... " + file.getAbsolutePath());
        });
        return handler;
    }

Answer 1

您可以使用 S3 事件通知和 SQS 队列。基本上，当一个对象被添加到您的存储桶中时，S3 可以将一个事件发布到一个已注册的 SQS 队列中。然后，您可以让您的本地应用程序长时间轮询队列以查找新事件并处理添加的任何事件。

有关详细信息，请参阅 here。

Answer 2

实际上，S3InboundFileSynchronizingMessageSource 会为您完成所有必要的工作：当新文件添加到远程存储桶时，它会下载到本地目录并在消息中生成为 payload被发送到配置的频道。

修改远程文件时，也会下载到本地

从版本 5.0 开始，AbstractInboundFileSynchronizingMessageSource 提供此选项：

/**
 * Switch the local {@link FileReadingMessageSource} to use its internal
 * {@code FileReadingMessageSource.WatchServiceDirectoryScanner}.
 * @param useWatchService the {@code boolean} flag to switch to
 * {@code FileReadingMessageSource.WatchServiceDirectoryScanner} on {@code true}.
 * @since 5.0
 */
public void setUseWatchService(boolean useWatchService) {
    this.fileSource.setUseWatchService(useWatchService);
    if (useWatchService) {
        this.fileSource.setWatchEvents(
                FileReadingMessageSource.WatchEventType.CREATE,
                FileReadingMessageSource.WatchEventType.MODIFY,
                FileReadingMessageSource.WatchEventType.DELETE);
    }
}

如果这对你有意义。

但是是的...通过 S3 到 SQS 通知，这也是一个很好的解决方案。 Spring Integration AWS 项目中有一个 SqsMessageDrivenChannelAdapter。

Answer 3

最后，正如@Artem Bilian 所建议的，我使用了 @ServiceActivator 注释。这是完整的示例：

import java.io.File;
import java.util.concurrent.TimeUnit;

import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.integration.annotation.InboundChannelAdapter;
import org.springframework.integration.annotation.Poller;
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.integration.aws.inbound.S3InboundFileSynchronizer;
import org.springframework.integration.aws.inbound.S3InboundFileSynchronizingMessageSource;
import org.springframework.integration.aws.support.S3SessionFactory;
import org.springframework.integration.aws.support.filters.S3RegexPatternFileListFilter;
import org.springframework.integration.channel.QueueChannel;
import org.springframework.integration.dsl.IntegrationFlow;
import org.springframework.integration.dsl.IntegrationFlows;
import org.springframework.integration.file.FileWritingMessageHandler;
import org.springframework.integration.file.support.FileExistsMode;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageHandler;
import org.springframework.messaging.PollableChannel;

import com.amazonaws.auth.AWSStaticCredentialsProvider;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;

import lombok.extern.log4j.Log4j2;

@Log4j2
@Configuration
public class S3Config {

    public static final String IN_CHANNEL_NAME = "s3filesChannel";

    @Value("${s3.credentials-access-key}") private String accessKey;
    @Value("${s3.credentials-secret-key}") private String secretKey;
    @Value("${s3.remote-dir}") private String remoteDir;
    @Value("${s3.bucket}") private String s3bucket;
    @Value("${s3.local-dir}") private String localDir;

    /*
     * AWS S3
     */
    @Bean
    public AmazonS3 getAmazonS3(

    ){
        BasicAWSCredentials creds = new BasicAWSCredentials(accessKey, secretKey);
        AmazonS3 s3client = AmazonS3ClientBuilder
                .standard()
                .withRegion(Regions.EU_WEST_1)
                .withCredentials(new AWSStaticCredentialsProvider(creds))
                .build();
        return s3client;        
    }

    @Bean
    public S3SessionFactory s3SessionFactory(AmazonS3 pAmazonS3) {
        return new S3SessionFactory(pAmazonS3);
    }

    @Bean
    public S3InboundFileSynchronizer s3InboundFileSynchronizer(S3SessionFactory pS3SessionFactory) {
        S3InboundFileSynchronizer sync = new S3InboundFileSynchronizer(pS3SessionFactory);
        sync.setPreserveTimestamp(true);
        sync.setDeleteRemoteFiles(false);
        String fullRemotePath = s3bucket.concat("/").concat(remoteDir);
        sync.setRemoteDirectory(fullRemotePath);
        sync.setFilter(new S3RegexPatternFileListFilter(".*\.zip$"));
        return sync;
    }

    @Bean
    @InboundChannelAdapter(value = IN_CHANNEL_NAME, poller = @Poller(fixedDelay = "30"))
    public S3InboundFileSynchronizingMessageSource s3InboundFileSynchronizingMessageSource(
        S3InboundFileSynchronizer pS3InboundFileSynchronizer
    ) {
        S3InboundFileSynchronizingMessageSource messageSource = new S3InboundFileSynchronizingMessageSource(pS3InboundFileSynchronizer);
        messageSource.setAutoCreateLocalDirectory(true);
        messageSource.setLocalDirectory(new File(localDir));
        messageSource.setUseWatchService(true);
        return messageSource;
    }

    @Bean("s3filesChannel")
    public PollableChannel s3FilesChannel() {
        return new QueueChannel();
    }

    @Bean
    public IntegrationFlow fileReadingFlow(
            S3InboundFileSynchronizingMessageSource pS3InboundFileSynchronizingMessageSource,
            @Qualifier("fileProcessor") MessageHandler pMessageHandler) {
        return IntegrationFlows
                .from(pS3InboundFileSynchronizingMessageSource, e -> e.poller(p -> p.fixedDelay(5, TimeUnit.SECONDS)))
                .handle(pMessageHandler)
                .get();
    }

    @Bean("fileProcessor")
    public MessageHandler fileProcessor() {
        FileWritingMessageHandler handler = new FileWritingMessageHandler(new File(localDir));
        handler.setExpectReply(false); // end of pipeline, reply not needed
        handler.setFileExistsMode(FileExistsMode.REPLACE);
        return handler;
    }

    @ServiceActivator(inputChannel = IN_CHANNEL_NAME, poller = @Poller(fixedDelay = "30"))
    public void asada(Message<?> message) {
        // TODO
        log.debug("<< New message!");
    }

}

请注意，我已将 OUT_CHANNEL_NAME 替换为 IN_CHANNEL_NAME。

PS：我几乎是 Spring 集成的新手，所以我仍在学习它的概念。

同步 S3 Bucket 并监听变化

Sync S3 Bucket and listen for changes

amazon-s3

spring-integration

spring-boot

spring-integration-aws