文档 AWS SDK 示例 GitHub 存储库中还有更多 [S AWS DK 示例](https://github.com/awsdocs/aws-doc-sdk-examples)。

本文属于机器翻译版本。若本译文内容与英语原文存在差异，则一律以英文原文为准。

# 使用适用于 Ruby 的 SDK 的 Amazon SNS 示例
<a name="ruby_3_sns_code_examples"></a>

以下代码示例向您展示了如何在 Amazon SNS 中使用来执行操作和实现常见场景。 适用于 Ruby 的 AWS SDK 

*操作*是大型程序的代码摘录，必须在上下文中运行。您可以通过操作了解如何调用单个服务函数，还可以通过函数相关场景的上下文查看操作。

每个示例都包含一个指向完整源代码的链接，您可以从中找到有关如何在上下文中设置和运行代码的说明。

**Topics**
+ [操作](#actions)
+ [无服务器示例](#serverless_examples)

## 操作
<a name="actions"></a>

### `CreateTopic`
<a name="sns_CreateTopic_ruby_3_topic"></a>

以下代码示例演示了如何使用 `CreateTopic`。

**适用于 Ruby 的 SDK**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/ruby/example_code/sns#code-examples)中查找完整示例，了解如何进行设置和运行。

```
# This class demonstrates how to create an Amazon Simple Notification Service (SNS) topic.
class SNSTopicCreator
  # Initializes an SNS client.
  #
  # Utilizes the default AWS configuration for region and credentials.
  def initialize
    @sns_client = Aws::SNS::Client.new
  end

  # Attempts to create an SNS topic with the specified name.
  #
  # @param topic_name [String] The name of the SNS topic to create.
  # @return [Boolean] true if the topic was successfully created, false otherwise.
  def create_topic(topic_name)
    @sns_client.create_topic(name: topic_name)
    puts "The topic '#{topic_name}' was successfully created."
    true
  rescue Aws::SNS::Errors::ServiceError => e
    # Handles SNS service errors gracefully.
    puts "Error while creating the topic named '#{topic_name}': #{e.message}"
    false
  end
end

# Example usage:
if $PROGRAM_NAME == __FILE__
  topic_name = 'YourTopicName' # Replace with your topic name
  sns_topic_creator = SNSTopicCreator.new

  puts "Creating the topic '#{topic_name}'..."
  unless sns_topic_creator.create_topic(topic_name)
    puts 'The topic was not created. Stopping program.'
    exit 1
  end
end
```
+  有关更多信息，请参阅《适用于 Ruby 的 AWS SDK 开发人员指南》[https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-create-topic.html](https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-create-topic.html)。
+  有关 API 的详细信息，请参阅 *适用于 Ruby 的 AWS SDK API 参考[CreateTopic](https://docs.aws.amazon.com/goto/SdkForRubyV3/sns-2010-03-31/CreateTopic)*中的。

### `ListSubscriptions`
<a name="sns_ListSubscriptions_ruby_3_topic"></a>

以下代码示例演示了如何使用 `ListSubscriptions`。

**适用于 Ruby 的 SDK**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/ruby/example_code/sns#code-examples)中查找完整示例，了解如何进行设置和运行。

```
# This class demonstrates how to list subscriptions to an Amazon Simple Notification Service (SNS) topic
class SnsSubscriptionLister
  def initialize(sns_client)
    @sns_client = sns_client
    @logger = Logger.new($stdout)
  end

  # Lists subscriptions for a given SNS topic
  # @param topic_arn [String] The ARN of the SNS topic
  # @return [Types::ListSubscriptionsResponse] subscriptions: The response object
  def list_subscriptions(topic_arn)
    @logger.info("Listing subscriptions for topic: #{topic_arn}")
    subscriptions = @sns_client.list_subscriptions_by_topic(topic_arn: topic_arn)
    subscriptions.subscriptions.each do |subscription|
      @logger.info("Subscription endpoint: #{subscription.endpoint}")
    end
    subscriptions
  rescue Aws::SNS::Errors::ServiceError => e
    @logger.error("Error listing subscriptions: #{e.message}")
    raise
  end
end

# Example usage:
if $PROGRAM_NAME == __FILE__
  sns_client = Aws::SNS::Client.new
  topic_arn = 'SNS_TOPIC_ARN' # Replace with your SNS topic ARN
  lister = SnsSubscriptionLister.new(sns_client)

  begin
    lister.list_subscriptions(topic_arn)
  rescue StandardError => e
    puts "Failed to list subscriptions: #{e.message}"
    exit 1
  end
end
```
+  有关更多信息，请参阅《适用于 Ruby 的 AWS SDK 开发人员指南》[https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-show-subscriptions.html](https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-show-subscriptions.html)。
+  有关 API 的详细信息，请参阅 *适用于 Ruby 的 AWS SDK API 参考[ListSubscriptions](https://docs.aws.amazon.com/goto/SdkForRubyV3/sns-2010-03-31/ListSubscriptions)*中的。

### `ListTopics`
<a name="sns_ListTopics_ruby_3_topic"></a>

以下代码示例演示了如何使用 `ListTopics`。

**适用于 Ruby 的 SDK**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/ruby/example_code/sns#code-examples)中查找完整示例，了解如何进行设置和运行。

```
require 'aws-sdk-sns' # v2: require 'aws-sdk'

def list_topics?(sns_client)
  sns_client.topics.each do |topic|
    puts topic.arn
  rescue StandardError => e
    puts "Error while listing the topics: #{e.message}"
  end
end

def run_me
  region = 'REGION'
  sns_client = Aws::SNS::Resource.new(region: region)

  puts 'Listing the topics.'

  return if list_topics?(sns_client)

  puts 'The bucket was not created. Stopping program.'
  exit 1
end

# Example usage:
run_me if $PROGRAM_NAME == __FILE__
```
+  有关更多信息，请参阅《适用于 Ruby 的 AWS SDK 开发人员指南》[https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-show-topics.html](https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-show-topics.html)。
+  有关 API 的详细信息，请参阅 *适用于 Ruby 的 AWS SDK API 参考[ListTopics](https://docs.aws.amazon.com/goto/SdkForRubyV3/sns-2010-03-31/ListTopics)*中的。

### `Publish`
<a name="sns_Publish_ruby_3_topic"></a>

以下代码示例演示了如何使用 `Publish`。

**适用于 Ruby 的 SDK**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/ruby/example_code/sns#code-examples)中查找完整示例，了解如何进行设置和运行。

```
# Service class for sending messages using Amazon Simple Notification Service (SNS)
class SnsMessageSender
  # Initializes the SnsMessageSender with an SNS client
  #
  # @param sns_client [Aws::SNS::Client] The SNS client
  def initialize(sns_client)
    @sns_client = sns_client
    @logger = Logger.new($stdout)
  end

  # Sends a message to a specified SNS topic
  #
  # @param topic_arn [String] The ARN of the SNS topic
  # @param message [String] The message to send
  # @return [Boolean] true if message was successfully sent, false otherwise
  def send_message(topic_arn, message)
    @sns_client.publish(topic_arn: topic_arn, message: message)
    @logger.info("Message sent successfully to #{topic_arn}.")
    true
  rescue Aws::SNS::Errors::ServiceError => e
    @logger.error("Error while sending the message: #{e.message}")
    false
  end
end

# Example usage:
if $PROGRAM_NAME == __FILE__
  topic_arn = 'SNS_TOPIC_ARN' # Should be replaced with a real topic ARN
  message = 'MESSAGE'         # Should be replaced with the actual message content

  sns_client = Aws::SNS::Client.new
  message_sender = SnsMessageSender.new(sns_client)

  @logger.info('Sending message.')
  unless message_sender.send_message(topic_arn, message)
    @logger.error('Message sending failed. Stopping program.')
    exit 1
  end
end
```
+  有关更多信息，请参阅《适用于 Ruby 的 AWS SDK 开发人员指南》[https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-send-message.html](https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-send-message.html)。
+  有关 API 的详细信息，请参阅 *适用于 Ruby 的 AWS SDK API 参考*中的 [Publish](https://docs.aws.amazon.com/goto/SdkForRubyV3/sns-2010-03-31/Publish)。

### `SetTopicAttributes`
<a name="sns_SetTopicAttributes_ruby_3_topic"></a>

以下代码示例演示了如何使用 `SetTopicAttributes`。

**适用于 Ruby 的 SDK**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/ruby/example_code/sns#code-examples)中查找完整示例，了解如何进行设置和运行。

```
# Service class to enable an SNS resource with a specified policy
class SnsResourceEnabler
  # Initializes the SnsResourceEnabler with an SNS resource client
  #
  # @param sns_resource [Aws::SNS::Resource] The SNS resource client
  def initialize(sns_resource)
    @sns_resource = sns_resource
    @logger = Logger.new($stdout)
  end

  # Sets a policy on a specified SNS topic
  #
  # @param topic_arn [String] The ARN of the SNS topic
  # @param resource_arn [String] The ARN of the resource to include in the policy
  # @param policy_name [String] The name of the policy attribute to set
  def enable_resource(topic_arn, resource_arn, policy_name)
    policy = generate_policy(topic_arn, resource_arn)
    topic = @sns_resource.topic(topic_arn)

    topic.set_attributes({
                           attribute_name: policy_name,
                           attribute_value: policy
                         })
    @logger.info("Policy #{policy_name} set successfully for topic #{topic_arn}.")
  rescue Aws::SNS::Errors::ServiceError => e
    @logger.error("Failed to set policy: #{e.message}")
  end

  private

  # Generates a policy string with dynamic resource ARNs
  #
  # @param topic_arn [String] The ARN of the SNS topic
  # @param resource_arn [String] The ARN of the resource
  # @return [String] The policy as a JSON string
  def generate_policy(topic_arn, resource_arn)
    {
      Version: '2008-10-17',
      Id: '__default_policy_ID',
      Statement: [{
        Sid: '__default_statement_ID',
        Effect: 'Allow',
        Principal: { "AWS": '*' },
        Action: ['SNS:Publish'],
        Resource: topic_arn,
        Condition: {
          ArnEquals: {
            "AWS:SourceArn": resource_arn
          }
        }
      }]
    }.to_json
  end
end

# Example usage:
if $PROGRAM_NAME == __FILE__
  topic_arn = 'MY_TOPIC_ARN' # Should be replaced with a real topic ARN
  resource_arn = 'MY_RESOURCE_ARN' # Should be replaced with a real resource ARN
  policy_name = 'POLICY_NAME' # Typically, this is "Policy"

  sns_resource = Aws::SNS::Resource.new
  enabler = SnsResourceEnabler.new(sns_resource)

  enabler.enable_resource(topic_arn, resource_arn, policy_name)
end
```
+  有关更多信息，请参阅《适用于 Ruby 的 AWS SDK 开发人员指南》[https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-enable-resource.html](https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-enable-resource.html)。
+  有关 API 的详细信息，请参阅 *适用于 Ruby 的 AWS SDK API 参考[SetTopicAttributes](https://docs.aws.amazon.com/goto/SdkForRubyV3/sns-2010-03-31/SetTopicAttributes)*中的。

### `Subscribe`
<a name="sns_Subscribe_ruby_3_topic"></a>

以下代码示例演示了如何使用 `Subscribe`。

**适用于 Ruby 的 SDK**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/ruby/example_code/sns#code-examples)中查找完整示例，了解如何进行设置和运行。
将电子邮件地址订阅到主题。  

```
require 'aws-sdk-sns'
require 'logger'

# Represents a service for creating subscriptions in Amazon Simple Notification Service (SNS)
class SubscriptionService
  # Initializes the SubscriptionService with an SNS client
  #
  # @param sns_client [Aws::SNS::Client] The SNS client
  def initialize(sns_client)
    @sns_client = sns_client
    @logger = Logger.new($stdout)
  end

  # Attempts to create a subscription to a topic
  #
  # @param topic_arn [String] The ARN of the SNS topic
  # @param protocol [String] The subscription protocol (e.g., email)
  # @param endpoint [String] The endpoint that receives the notifications (email address)
  # @return [Boolean] true if subscription was successfully created, false otherwise
  def create_subscription(topic_arn, protocol, endpoint)
    @sns_client.subscribe(topic_arn: topic_arn, protocol: protocol, endpoint: endpoint)
    @logger.info('Subscription created successfully.')
    true
  rescue Aws::SNS::Errors::ServiceError => e
    @logger.error("Error while creating the subscription: #{e.message}")
    false
  end
end

# Main execution if the script is run directly
if $PROGRAM_NAME == __FILE__
  protocol = 'email'
  endpoint = 'EMAIL_ADDRESS' # Should be replaced with a real email address
  topic_arn = 'TOPIC_ARN'    # Should be replaced with a real topic ARN

  sns_client = Aws::SNS::Client.new
  subscription_service = SubscriptionService.new(sns_client)

  @logger.info('Creating the subscription.')
  unless subscription_service.create_subscription(topic_arn, protocol, endpoint)
    @logger.error('Subscription creation failed. Stopping program.')
    exit 1
  end
end
```
+  有关更多信息，请参阅《适用于 Ruby 的 AWS SDK 开发人员指南》[https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-create-subscription.html](https://docs.aws.amazon.com/sdk-for-ruby/v3/developer-guide/sns-example-create-subscription.html)。
+  有关 API 详细信息，请参阅《适用于 Ruby 的 AWS SDK API Reference》**中的 [Subscribe](https://docs.aws.amazon.com/goto/SdkForRubyV3/sns-2010-03-31/Subscribe)。

## 无服务器示例
<a name="serverless_examples"></a>

### 通过 Amazon SNS 触发器调用 Lambda 函数
<a name="serverless_SNS_Lambda_ruby_3_topic"></a>

以下代码示例展示了如何实现一个 Lambda 函数，该函数接收因接收来自 SNS 主题的消息而触发的事件。该函数从事件参数检索消息并记录每条消息的内容。

**适用于 Ruby 的 SDK**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-sns-to-lambda)存储库中查找完整示例，并了解如何进行设置和运行。
通过 Ruby 将 SNS 事件与 Lambda 结合使用。  

```
# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
# SPDX-License-Identifier: Apache-2.0
def lambda_handler(event:, context:)
  event['Records'].map { |record| process_message(record) }
end

def process_message(record)
  message = record['Sns']['Message']
  puts("Processing message: #{message}")
rescue StandardError => e
  puts("Error processing message: #{e}")
  raise
end
```