Question

我在桌面应用程序中使用google cloud pubsub java library。我为特定主题创建订阅并从中接收数据。我想知道是否可以配置订阅的邮件保留期限。我在任何地方都找不到。谢谢。

为使问题更清楚，我粘贴了用于创建订阅的代码块：

String topicName = "some-topic";
String subscriptionName = "some-subscription";
ProjectTopicName topic = ProjectTopicName.of(PROJECT_ID, topicName);
ProjectSubscriptionName subscription = ProjectSubscriptionName.of(PROJECT_ID, subscriptionName);
SubscriptionAdminClient subscriptionAdminClient = SubscriptionAdminClient.create(); // I reuse this object so I create it in advance
try {
   subscriptionAdminClient.createSubscription(subscription,
        topic,
        PushConfig.getDefaultInstance(),
        0
   );
} catch (ApiException e) {
   if (e.getStatusCode().getCode() != StatusCode.Code.ALREADY_EXISTS) {
        subscriptionAdminClient.close();
   }
}

Answer 1

您可以使用Java配置订阅的消息保留期限。创建598 * 3600 * 1000 = 2,152,800,000对象时，可以在创建请求中提供message_retention_duration field。要在Java中执行此操作，请使用setMessageRetentionDuration method on Subscription.Builder对象，如本例所示（使用long依赖项）：

Subscription

请注意，com.google.cloud:google-cloud-pubsub:1.86.0采用Duration作为参数，因此您可能需要使用Durations helper class（例如package com.example; import com.google.cloud.pubsub.v1.SubscriptionAdminClient; import com.google.pubsub.v1.Subscription; import com.google.pubsub.v1.TopicName; import com.google.protobuf.util.Durations; import java.io.IOException; public class PubSubCreateSubscription { static Subscription createSubscriptionWithMessageRetentionDuration( String topicName, String subscriptionName, long messageRetentionDurationInMillis ) throws IOException { try (SubscriptionAdminClient subscriptionAdminClient = SubscriptionAdminClient.create()) { Subscription request = Subscription.newBuilder() .setName(subscriptionName) .setTopic(topicName) .setMessageRetentionDuration(Durations .fromMillis(messageRetentionDurationInMillis)) .build(); return subscriptionAdminClient .createSubscription(request); } } public static void main(String[] args) { String topicName = "projects/[PROJECT]/topics/[TOPIC_NAME]"; String subscriptionName = "projects/[PROJECT]/subscriptions/[SUBSCRIPTION_NAME]"; try { Subscription mySubscription = createSubscriptionWithMessageRetentionDuration( topicName, subscriptionName, 600000 // 600 000 ms = 10 minutes ); // [...] } catch (IOException e) { e.printStackTrace(); } } }方法）将毫秒转换为protobuf {{ 1}}。还要注意from the REST resource documentation，此字段：

不能超过7天或少于10分钟。

使用Java客户端库配置PubSub的消息保留期限

1 个答案: