指定 Amazon SQS 中的消息可见性超时 - Amazon 适用于 Ruby 的 SDK
先决条件示例
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指定 Amazon SQS 中的消息可见性超时

Amazon SQS 在收到消息后，会立即将消息保留在队列中。为防止其他用户再次处理消息，Amazon SQS 会设置可见性超时。这是 Amazon SQS 阻止其他使用组件接收并处理消息的一段时间。要了解更多信息，请参阅可见性超时。

在此示例中，您结合使用适用于 Ruby 的 Amazon SDK 和 Amazon SQS 以实现如下用途：

  1. 通过使用 Aws::SQS::Client#get_queue_url 来获取现有队列的 URL。

  2. 通过使用 Aws::SQS::Client#receive_message 来接收最多 10 个消息。

  3. 通过使用 Aws::SQS::Client#change_message_visibility 来指定在收到消息后消息不可见的时间间隔。

先决条件

在运行示例代码之前，您需要安装并配置适用于 Ruby 的 Amazon SDK，如以下文档所述：

您还需要创建队列 my-queue，您可以在 Amazon SQS 控制台中执行此操作。

示例

# Copyright 2010-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
#
# This file is licensed under the Apache License, Version 2.0 (the "License").
# You may not use this file except in compliance with the License. A copy of the
# License is located at
#
# http://aws.amazon.com/apache2.0/
#
# This file 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.

# Demonstrates how to specify the time interval during which messages to a queue are not visible after being received.

require 'aws-sdk-sqs'  # v2: require 'aws-sdk'

sqs = Aws::SQS::Client.new(region: 'us-east-1')

begin
  queue_name = "my-queue"
  queue_url = sqs.get_queue_url(queue_name: queue_name).queue_url

  receive_message_result_before = sqs.receive_message({
    queue_url: queue_url,    
    max_number_of_messages: 10 # Receive up to 10 messages, if there are that many.
  })

  puts "Before attempting to change message visibility timeout: received #{receive_message_result_before.messages.count} message(s)."

  receive_message_result_before.messages.each do |message|
    sqs.change_message_visibility({
      queue_url: queue_url,
      receipt_handle: message.receipt_handle,
      visibility_timeout: 30 # This message will not be visible for 30 seconds after first receipt.
    })    
  end  

  # Try to retrieve the original messages after setting their visibility timeout. 
  receive_message_result_after = sqs.receive_message({
    queue_url: queue_url,
    max_number_of_messages: 10
  })

  puts "\nAfter attempting to change message visibility timeout: received #{receive_message_result_after.messages.count} message(s)."

rescue Aws::SQS::Errors::NonExistentQueue
  puts "Cannot receive messages for a queue named '#{receive_queue_name}', as it does not exist."
end