Utilizzare ReceiveMessage con un SDK AWS o una CLI

Riceve messaggi da una coda utilizzando il relativo URL.

    /// <summary>
    /// Receive messages from a queue by its URL.
    /// </summary>
    /// <param name="queueUrl">The url of the queue.</param>
    /// <returns>The list of messages.</returns>
    public async Task<List<Message>> ReceiveMessagesByUrl(string queueUrl, int maxMessages)
    {
        // Setting WaitTimeSeconds to non-zero enables long polling.
        // For information about long polling, see
        // https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-short-and-long-polling.html
        var messageResponse = await _amazonSQSClient.ReceiveMessageAsync(
            new ReceiveMessageRequest()
            {
                QueueUrl = queueUrl,
                MaxNumberOfMessages = maxMessages,
                WaitTimeSeconds = 1
            });
        return messageResponse.Messages;
    }

Riceve un messaggio da una coda Amazon SQS e poi elimina il messaggio.

        public static async Task Main()
        {
            // If the AWS Region you want to use is different from
            // the AWS Region defined for the default user, supply
            // the specify your AWS Region to the client constructor.
            var client = new AmazonSQSClient();
            string queueName = "Example_Queue";

            var queueUrl = await GetQueueUrl(client, queueName);
            Console.WriteLine($"The SQS queue's URL is {queueUrl}");

            var response = await ReceiveAndDeleteMessage(client, queueUrl);

            Console.WriteLine($"Message: {response.Messages[0]}");
        }

        /// <summary>
        /// Retrieve the queue URL for the queue named in the queueName
        /// property using the client object.
        /// </summary>
        /// <param name="client">The Amazon SQS client used to retrieve the
        /// queue URL.</param>
        /// <param name="queueName">A string representing  name of the queue
        /// for which to retrieve the URL.</param>
        /// <returns>The URL of the queue.</returns>
        public static async Task<string> GetQueueUrl(IAmazonSQS client, string queueName)
        {
            var request = new GetQueueUrlRequest
            {
                QueueName = queueName,
            };

            GetQueueUrlResponse response = await client.GetQueueUrlAsync(request);
            return response.QueueUrl;
        }

        /// <summary>
        /// Retrieves the message from the quque at the URL passed in the
        /// queueURL parameters using the client.
        /// </summary>
        /// <param name="client">The SQS client used to retrieve a message.</param>
        /// <param name="queueUrl">The URL of the queue from which to retrieve
        /// a message.</param>
        /// <returns>The response from the call to ReceiveMessageAsync.</returns>
        public static async Task<ReceiveMessageResponse> ReceiveAndDeleteMessage(IAmazonSQS client, string queueUrl)
        {
            // Receive a single message from the queue.
            var receiveMessageRequest = new ReceiveMessageRequest
            {
                AttributeNames = { "SentTimestamp" },
                MaxNumberOfMessages = 1,
                MessageAttributeNames = { "All" },
                QueueUrl = queueUrl,
                VisibilityTimeout = 0,
                WaitTimeSeconds = 0,
            };

            var receiveMessageResponse = await client.ReceiveMessageAsync(receiveMessageRequest);

            // Delete the received message from the queue.
            var deleteMessageRequest = new DeleteMessageRequest
            {
                QueueUrl = queueUrl,
                ReceiptHandle = receiveMessageResponse.Messages[0].ReceiptHandle,
            };

            await client.DeleteMessageAsync(deleteMessageRequest);

            return receiveMessageResponse;
        }
    }

        Aws::Client::ClientConfiguration clientConfig;
        // Optional: Set to the AWS Region (overrides config file).
        // clientConfig.region = "us-east-1";

//! Receive a message from an Amazon Simple Queue Service (Amazon SQS) queue.
/*!
  \param queueUrl: An Amazon SQS queue URL.
  \param clientConfiguration: AWS client configuration.
  \return bool: Function succeeded.
 */
bool AwsDoc::SQS::receiveMessage(const Aws::String &queueUrl,
                                 const Aws::Client::ClientConfiguration &clientConfiguration) {
    Aws::SQS::SQSClient sqsClient(clientConfiguration);

    Aws::SQS::Model::ReceiveMessageRequest request;
    request.SetQueueUrl(queueUrl);
    request.SetMaxNumberOfMessages(1);

    const Aws::SQS::Model::ReceiveMessageOutcome outcome = sqsClient.ReceiveMessage(
            request);
    if (outcome.IsSuccess()) {

        const Aws::Vector<Aws::SQS::Model::Message> &messages =
                outcome.GetResult().GetMessages();
        if (!messages.empty()) {
            const Aws::SQS::Model::Message &message = messages[0];
            std::cout << "Received message:" << std::endl;
            std::cout << "  MessageId: " << message.GetMessageId() << std::endl;
            std::cout << "  ReceiptHandle: " << message.GetReceiptHandle() << std::endl;
            std::cout << "  Body: " << message.GetBody() << std::endl << std::endl;
        }
        else {
            std::cout << "No messages received from queue " << queueUrl <<
                      std::endl;

        }
    }
    else {
        std::cerr << "Error receiving message from queue " << queueUrl << ": "
                  << outcome.GetError().GetMessage() << std::endl;
    }
    return outcome.IsSuccess();
}

Come ricevere un messaggio

Questo esempio riceve fino a 10 messaggi disponibili e restituisce tutti gli attributi disponibili.

Comando:

aws sqs receive-message --queue-url https://sqs.us-east-1.amazonaws.com/80398EXAMPLE/MyQueue --attribute-names All --message-attribute-names All --max-number-of-messages 10

Output:

{
  "Messages": [
    {
      "Body": "My first message.",
      "ReceiptHandle": "AQEBzbVv...fqNzFw==",
      "MD5OfBody": "1000f835...a35411fa",
      "MD5OfMessageAttributes": "9424c491...26bc3ae7",
      "MessageId": "d6790f8d-d575-4f01-bc51-40122EXAMPLE",
      "Attributes": {
        "ApproximateFirstReceiveTimestamp": "1442428276921",
        "SenderId": "AIDAIAZKMSNQ7TEXAMPLE",
        "ApproximateReceiveCount": "5",
        "SentTimestamp": "1442428276921"
      },
      "MessageAttributes": {
        "PostalCode": {
          "DataType": "String",
          "StringValue": "ABC123"
        },
        "City": {
          "DataType": "String",
          "StringValue": "Any City"
        }
      }
    }
  ]
}

Questo esempio riceve il successivo messaggio disponibile e restituisce solo gli attributi SenderId e SentTimestamp e l’attributo PostalCode del messaggio.

Comando:

aws sqs receive-message --queue-url https://sqs.us-east-1.amazonaws.com/80398EXAMPLE/MyQueue --attribute-names SenderId SentTimestamp --message-attribute-names PostalCode

Output:

{
  "Messages": [
    {
      "Body": "My first message.",
      "ReceiptHandle": "AQEB6nR4...HzlvZQ==",
      "MD5OfBody": "1000f835...a35411fa",
      "MD5OfMessageAttributes": "b8e89563...e088e74f",
      "MessageId": "d6790f8d-d575-4f01-bc51-40122EXAMPLE",
      "Attributes": {
        "SenderId": "AIDAIAZKMSNQ7TEXAMPLE",
        "SentTimestamp": "1442428276921"
      },
      "MessageAttributes": {
        "PostalCode": {
          "DataType": "String",
          "StringValue": "ABC123"
        }
      }
    }
  ]
}

import (
	"context"
	"encoding/json"
	"fmt"
	"log"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/sqs"
	"github.com/aws/aws-sdk-go-v2/service/sqs/types"
)

// SqsActions encapsulates the Amazon Simple Queue Service (Amazon SQS) actions
// used in the examples.
type SqsActions struct {
	SqsClient *sqs.Client
}



// GetMessages uses the ReceiveMessage action to get messages from an Amazon SQS queue.
func (actor SqsActions) GetMessages(ctx context.Context, queueUrl string, maxMessages int32, waitTime int32) ([]types.Message, error) {
	var messages []types.Message
	result, err := actor.SqsClient.ReceiveMessage(ctx, &sqs.ReceiveMessageInput{
		QueueUrl:            aws.String(queueUrl),
		MaxNumberOfMessages: maxMessages,
		WaitTimeSeconds:     waitTime,
	})
	if err != nil {
		log.Printf("Couldn't get messages from queue %v. Here's why: %v\n", queueUrl, err)
	} else {
		messages = result.Messages
	}
	return messages, err
}

        try {
            ReceiveMessageRequest receiveMessageRequest = ReceiveMessageRequest.builder()
                    .queueUrl(queueUrl)
                    .maxNumberOfMessages(5)
                    .build();
            return sqsClient.receiveMessage(receiveMessageRequest).messages();

        } catch (SqsException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
            System.exit(1);
        }
        return null;

Riceve un messaggio da una coda Amazon SQS.

import {
  ReceiveMessageCommand,
  DeleteMessageCommand,
  SQSClient,
  DeleteMessageBatchCommand,
} from "@aws-sdk/client-sqs";

const client = new SQSClient({});
const SQS_QUEUE_URL = "queue_url";

const receiveMessage = (queueUrl) =>
  client.send(
    new ReceiveMessageCommand({
      AttributeNames: ["SentTimestamp"],
      MaxNumberOfMessages: 10,
      MessageAttributeNames: ["All"],
      QueueUrl: queueUrl,
      WaitTimeSeconds: 20,
      VisibilityTimeout: 20,
    }),
  );

export const main = async (queueUrl = SQS_QUEUE_URL) => {
  const { Messages } = await receiveMessage(queueUrl);

  if (!Messages) {
    return;
  }

  if (Messages.length === 1) {
    console.log(Messages[0].Body);
    await client.send(
      new DeleteMessageCommand({
        QueueUrl: queueUrl,
        ReceiptHandle: Messages[0].ReceiptHandle,
      }),
    );
  } else {
    await client.send(
      new DeleteMessageBatchCommand({
        QueueUrl: queueUrl,
        Entries: Messages.map((message) => ({
          Id: message.MessageId,
          ReceiptHandle: message.ReceiptHandle,
        })),
      }),
    );
  }
};

Riceve un messaggio da una coda Amazon SQS utilizzando il supporto del long polling.

import { ReceiveMessageCommand, SQSClient } from "@aws-sdk/client-sqs";

const client = new SQSClient({});
const SQS_QUEUE_URL = "queue-url";

export const main = async (queueUrl = SQS_QUEUE_URL) => {
  const command = new ReceiveMessageCommand({
    AttributeNames: ["SentTimestamp"],
    MaxNumberOfMessages: 1,
    MessageAttributeNames: ["All"],
    QueueUrl: queueUrl,
    // The duration (in seconds) for which the call waits for a message
    // to arrive in the queue before returning. If a message is available,
    // the call returns sooner than WaitTimeSeconds. If no messages are
    // available and the wait time expires, the call returns successfully
    // with an empty list of messages.
    // https://docs.aws.amazon.com/AWSSimpleQueueService/latest/APIReference/API_ReceiveMessage.html#API_ReceiveMessage_RequestSyntax
    WaitTimeSeconds: 20,
  });

  const response = await client.send(command);
  console.log(response);
  return response;
};

Riceve un messaggio da una coda Amazon SQS utilizzando il supporto del long polling.

// Load the AWS SDK for Node.js
var AWS = require("aws-sdk");
// Set the region
AWS.config.update({ region: "REGION" });

// Create the SQS service object
var sqs = new AWS.SQS({ apiVersion: "2012-11-05" });

var queueURL = "SQS_QUEUE_URL";

var params = {
  AttributeNames: ["SentTimestamp"],
  MaxNumberOfMessages: 1,
  MessageAttributeNames: ["All"],
  QueueUrl: queueURL,
  WaitTimeSeconds: 20,
};

sqs.receiveMessage(params, function (err, data) {
  if (err) {
    console.log("Error", err);
  } else {
    console.log("Success", data);
  }
});

suspend fun receiveMessages(queueUrlVal: String?) {
    println("Retrieving messages from $queueUrlVal")

    val receiveMessageRequest =
        ReceiveMessageRequest {
            queueUrl = queueUrlVal
            maxNumberOfMessages = 5
        }

    SqsClient.fromEnvironment { region = "us-east-1" }.use { sqsClient ->
        val response = sqsClient.receiveMessage(receiveMessageRequest)
        response.messages?.forEach { message ->
            println(message.body)
        }
    }
}

Esempio 1: questo esempio elenca le informazioni per un massimo di 10 messaggi da ricevere per la coda specificata. Le informazioni conterranno i valori degli attributi del messaggio specificati, se esistenti.

Receive-SQSMessage -AttributeName SenderId, SentTimestamp -MessageAttributeName StudentName, StudentGrade -MessageCount 10 -QueueUrl https://sqs.us-east-1.amazonaws.com/80398EXAMPLE/MyQueue

Output:

Attributes             : {[SenderId, AIDAIAZKMSNQ7TEXAMPLE], [SentTimestamp, 1451495923744]}
Body                   : Information about John Doe's grade.
MD5OfBody              : ea572796e3c231f974fe75d89EXAMPLE
MD5OfMessageAttributes : 48c1ee811f0fe7c4e88fbe0f5EXAMPLE
MessageAttributes      : {[StudentGrade, Amazon.SQS.Model.MessageAttributeValue], [StudentName, Amazon.SQS.Model.MessageAttributeValue]}
MessageId              : 53828c4b-631b-469b-8833-c093cEXAMPLE
ReceiptHandle          : AQEBpfGp...20Q5cg==

Esempio 1: questo esempio elenca le informazioni per un massimo di 10 messaggi da ricevere per la coda specificata. Le informazioni conterranno i valori degli attributi del messaggio specificati, se esistenti.

Receive-SQSMessage -AttributeName SenderId, SentTimestamp -MessageAttributeName StudentName, StudentGrade -MessageCount 10 -QueueUrl https://sqs.us-east-1.amazonaws.com/80398EXAMPLE/MyQueue

Output:

Attributes             : {[SenderId, AIDAIAZKMSNQ7TEXAMPLE], [SentTimestamp, 1451495923744]}
Body                   : Information about John Doe's grade.
MD5OfBody              : ea572796e3c231f974fe75d89EXAMPLE
MD5OfMessageAttributes : 48c1ee811f0fe7c4e88fbe0f5EXAMPLE
MessageAttributes      : {[StudentGrade, Amazon.SQS.Model.MessageAttributeValue], [StudentName, Amazon.SQS.Model.MessageAttributeValue]}
MessageId              : 53828c4b-631b-469b-8833-c093cEXAMPLE
ReceiptHandle          : AQEBpfGp...20Q5cg==

def receive_messages(queue, max_number, wait_time):
    """
    Receive a batch of messages in a single request from an SQS queue.

    :param queue: The queue from which to receive messages.
    :param max_number: The maximum number of messages to receive. The actual number
                       of messages received might be less.
    :param wait_time: The maximum time to wait (in seconds) before returning. When
                      this number is greater than zero, long polling is used. This
                      can result in reduced costs and fewer false empty responses.
    :return: The list of Message objects received. These each contain the body
             of the message and metadata and custom attributes.
    """
    try:
        messages = queue.receive_messages(
            MessageAttributeNames=["All"],
            MaxNumberOfMessages=max_number,
            WaitTimeSeconds=wait_time,
        )
        for msg in messages:
            logger.info("Received message: %s: %s", msg.message_id, msg.body)
    except ClientError as error:
        logger.exception("Couldn't receive messages from queue: %s", queue)
        raise error
    else:
        return messages

require 'aws-sdk-sqs'
require 'aws-sdk-sts'

# Receives messages in a queue in Amazon Simple Queue Service (Amazon SQS).
#
# @param sqs_client [Aws::SQS::Client] An initialized Amazon SQS client.
# @param queue_url [String] The URL of the queue.
# @param max_number_of_messages [Integer] The maximum number of messages
#   to receive. This number must be 10 or less. The default is 10.
# @example
#   receive_messages(
#     Aws::SQS::Client.new(region: 'us-west-2'),
#     'https://sqs.us-west-2.amazonaws.com/111111111111/my-queue',
#     10
#   )
def receive_messages(sqs_client, queue_url, max_number_of_messages = 10)
  if max_number_of_messages > 10
    puts 'Maximum number of messages to receive must be 10 or less. ' \
      'Stopping program.'
    return
  end

  response = sqs_client.receive_message(
    queue_url: queue_url,
    max_number_of_messages: max_number_of_messages
  )

  if response.messages.count.zero?
    puts 'No messages to receive, or all messages have already ' \
      'been previously received.'
    return
  end

  response.messages.each do |message|
    puts '-' * 20
    puts "Message body: #{message.body}"
    puts "Message ID:   #{message.message_id}"
  end
rescue StandardError => e
  puts "Error receiving messages: #{e.message}"
end

# Full example call:
# Replace us-west-2 with the AWS Region you're using for Amazon SQS.
def run_me
  region = 'us-west-2'
  queue_name = 'my-queue'
  max_number_of_messages = 10

  sts_client = Aws::STS::Client.new(region: region)

  # For example:
  # 'https://sqs.us-west-2.amazonaws.com/111111111111/my-queue'
  queue_url = "https://sqs.#{region}.amazonaws.com/#{sts_client.get_caller_identity.account}/#{queue_name}"

  sqs_client = Aws::SQS::Client.new(region: region)

  puts "Receiving messages from queue '#{queue_name}'..."

  receive_messages(sqs_client, queue_url, max_number_of_messages)
end

# Example usage:
run_me if $PROGRAM_NAME == __FILE__

async fn receive(client: &Client, queue_url: &String) -> Result<(), Error> {
    let rcv_message_output = client.receive_message().queue_url(queue_url).send().await?;

    println!("Messages from queue with url: {}", queue_url);

    for message in rcv_message_output.messages.unwrap_or_default() {
        println!("Got the message: {:#?}", message);
    }

    Ok(())
}

Riceve un messaggio da una coda Amazon SQS.

    TRY.
        oo_result = lo_sqs->receivemessage( iv_queueurl = iv_queue_url ).    " oo_result is returned for testing purposes. "
        DATA(lt_messages) = oo_result->get_messages( ).
        MESSAGE 'Message received from SQS queue.' TYPE 'I'.
      CATCH /aws1/cx_sqsoverlimit.
        MESSAGE 'Maximum number of in-flight messages reached.' TYPE 'E'.
    ENDTRY.

Riceve un messaggio da una coda Amazon SQS utilizzando il supporto del long polling.

    TRY.
        oo_result = lo_sqs->receivemessage(           " oo_result is returned for testing purposes. "
                iv_queueurl = iv_queue_url
                iv_waittimeseconds = iv_wait_time ).    " Time in seconds for long polling, such as how long the call waits for a message to arrive in the queue before returning. " ).
        DATA(lt_messages) = oo_result->get_messages( ).
        MESSAGE 'Message received from SQS queue.' TYPE 'I'.
      CATCH /aws1/cx_sqsoverlimit.
        MESSAGE 'Maximum number of in-flight messages reached.' TYPE 'E'.
    ENDTRY.

import AWSSQS

        let config = try await SQSClient.SQSClientConfiguration(region: region)
        let sqsClient = SQSClient(config: config)

        let output = try await sqsClient.receiveMessage(
            input: ReceiveMessageInput(
                maxNumberOfMessages: maxMessages,
                queueUrl: url
            )
        )

        guard let messages = output.messages else {
            print("No messages received.")
            return
        }
    
        for message in messages {
            print("Message ID:     \(message.messageId ?? "<unknown>")")
            print("Receipt handle: \(message.receiptHandle ?? "<unknown>")")
            print(message.body ?? "<body missing>")
            print("---")
        }