v1 通过流控制进行订阅（已废弃）

（已弃用）通过流控制进行订阅

代码示例

Go

在尝试此示例之前，请按照《Pub/Sub 快速入门：使用客户端库》中的 Go 设置说明执行操作。如需了解详情，请参阅 Pub/Sub Go API 参考文档。

如需向 Pub/Sub 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

import (
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/pubsub"
)

func pullMsgsFlowControlSettings(w io.Writer, projectID, subID string) error {
	// projectID := "my-project-id"
	// subID := "my-sub"
	ctx := context.Background()
	client, err := pubsub.NewClient(ctx, projectID)
	if err != nil {
		return fmt.Errorf("pubsub.NewClient: %w", err)
	}
	defer client.Close()

	sub := client.Subscription(subID)
	// MaxOutstandingMessages is the maximum number of unprocessed messages the
	// subscriber client will pull from the server before pausing. This also configures
	// the maximum number of concurrent handlers for received messages.
	//
	// For more information, see https://cloud.google.com/pubsub/docs/pull#streamingpull_dealing_with_large_backlogs_of_small_messages.
	sub.ReceiveSettings.MaxOutstandingMessages = 100
	// MaxOutstandingBytes is the maximum size of unprocessed messages,
	// that the subscriber client will pull from the server before pausing.
	sub.ReceiveSettings.MaxOutstandingBytes = 1e8
	err = sub.Receive(ctx, func(ctx context.Context, msg *pubsub.Message) {
		fmt.Fprintf(w, "Got message: %q\n", string(msg.Data))
		msg.Ack()
	})
	if err != nil {
		return fmt.Errorf("sub.Receive: %w", err)
	}
	return nil
}

Ruby

在尝试此示例之前，请按照《Pub/Sub 快速入门：使用客户端库》中的 Ruby 设置说明执行操作。如需了解详情，请参阅 Pub/Sub Ruby API 参考文档。

如需向 Pub/Sub 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

# subscription_id = "your-subscription-id"

pubsub = Google::Cloud::Pubsub.new

subscription = pubsub.subscription subscription_id
subscriber   = subscription.listen inventory: 10 do |received_message|
  puts "Received message: #{received_message.data}"
  received_message.acknowledge!
end

subscriber.start
# Let the main thread sleep for 60 seconds so the thread for listening
# messages does not quit
sleep 60
subscriber.stop.wait!

后续步骤

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