Amazon SQS Block

Interact with Amazon Simple Queue Service (SQS): send messages, receive messages, and list queues. Authenticate with AWS access key credentials (SigV4 signed). Reach for this block whenever a workflow needs to enqueue work items, drain a queue for downstream processing, or discover available queues in an AWS account.

Overview

When to Use

• Send a task or event payload to an SQS queue so a consumer service can pick it up asynchronously.
• Poll an SQS queue and pull pending messages into the workflow for processing.
• Discover all queues in an AWS region, optionally filtered by a name prefix.
• Fan-out events: place a message on multiple queues from a single workflow step.
• Bridge Zelaxy workflows to AWS-native microservices that communicate over SQS.
• Trigger downstream workflows by placing messages that another listener polls.

Configuration

Operation

Required. Selects which SQS API action to perform. The visible fields below change based on this selection.

Default: sqs_send_message.

Queue URL

Visible for: sqs_send_message, sqs_receive_message.

The full HTTPS URL of the target SQS queue, for example https://sqs.us-east-1.amazonaws.com/123456789012/my-queue. You can reference another block's output with {{blockName.data.QueueUrl}} or store the URL as a workflow variable and reference it with {{variables.queueUrl}}.

Message Body

Visible for: sqs_send_message only.

The text content to send as the message body. Accepts any string, including JSON payloads produced by upstream blocks (e.g. {{agent_1.data}}).

Max Messages

Visible for: sqs_receive_message only. Optional.

Maximum number of messages to return in a single call. Accepts values 1–10; defaults to 10 when left blank.

Queue Name Prefix

Visible for: sqs_list_queues only. Optional.

Filter the returned queue list to queues whose names begin with this string. Leave blank to return all queues in the region.

AWS Region

Required (all operations). The AWS region where the queue exists, e.g. us-east-1. Store this in a workflow variable and reference it with {{variables.awsRegion}} to avoid hardcoding it.

AWS Access Key ID

Required (all operations). The AWS IAM access key ID with permission to call SQS. Store credentials as secrets and reference with {{AWS_ACCESS_KEY_ID}}.

AWS Secret Access Key

Required (all operations). The AWS IAM secret access key corresponding to the Access Key ID. Store credentials as secrets and reference with {{AWS_SECRET_ACCESS_KEY}}.

Inputs & Outputs

Inputs:

• operation (string) — Operation to perform (sqs_send_message, sqs_receive_message, or sqs_list_queues)
• awsRegion (string) — AWS region (e.g. us-east-1)
• awsAccessKeyId (string) — AWS access key ID
• awsSecretAccessKey (string) — AWS secret access key
• queueUrl (string) — SQS queue URL (required for send and receive operations)
• messageBody (string) — Message body (required for send operation)
• maxMessages (number) — Max messages to receive (used for receive operation; 1–10, default 10)
• prefix (string) — Queue name prefix filter (used for list operation)

Outputs:

• data (json) — Raw SQS API response object. Shape varies by operation:
  • sqs_send_message: contains MessageId, MD5OfMessageBody, and related fields.
  • sqs_receive_message: contains a Messages array where each item has MessageId, Body, ReceiptHandle, and more.
  • sqs_list_queues: contains a QueueUrls array of queue URL strings.

Tools

• SQS Send Message (sqs_send_message) — Posts a single message to the specified SQS queue using AmazonSQS.SendMessage. Requires queueUrl and messageBody.
• SQS Receive Messages (sqs_receive_message) — Polls the specified SQS queue for up to maxMessages messages using AmazonSQS.ReceiveMessage. Returns a Messages array; messages are NOT automatically deleted after receipt.
• SQS List Queues (sqs_list_queues) — Lists all SQS queues in the region using AmazonSQS.ListQueues, optionally filtered by a prefix. Returns a QueueUrls array.

All three tools sign requests with AWS SigV4 (awsJsonHeaders).

YAML Example

sqs_1:
  type: sqs
  name: "Amazon SQS"
  inputs:
    operation: "sqs_send_message"
    awsRegion: "{{variables.awsRegion}}"
    awsAccessKeyId: "{{AWS_ACCESS_KEY_ID}}"
    awsSecretAccessKey: "{{AWS_SECRET_ACCESS_KEY}}"
    queueUrl: "https://sqs.us-east-1.amazonaws.com/123456789012/my-queue"
    messageBody: "{{agent_1.data}}"
  connections:
    outgoing:
      - target: next-block-id