openapi: 3.0.3
info:
  title: QStash Dead Letter Queue API
  description: QStash is a serverless message queue and task scheduling REST API from Upstash that delivers HTTP messages to endpoints reliably without requiring any long-lived connections or infrastructure management. Built entirely on stateless HTTP requests, it is designed for serverless and edge runtimes where traditional message brokers are impractical. QStash supports automatic retries, CRON-based scheduling up to one year in advance, URL group broadcasting for fan-out delivery, FIFO queuing, dead-letter queues, and message deduplication.
  version: '2.0'
  contact:
    name: Upstash Support
    url: https://upstash.com/docs/qstash/overall/getstarted
  license:
    name: Upstash Terms of Service
    url: https://upstash.com/trust/terms.pdf
servers:
- url: https://qstash.upstash.io/v2
  description: QStash production API
security:
- BearerAuth: []
tags:
- name: Dead Letter Queue
  description: Manage dead letter queue messages
paths:
  /dlq:
    get:
      operationId: listDlqMessages
      summary: List dead letter queue messages
      description: Retrieve messages that have been moved to the dead letter queue after exhausting all delivery retries.
      tags:
      - Dead Letter Queue
      parameters:
      - name: cursor
        in: query
        description: Pagination cursor from previous response
        schema:
          type: string
      - name: count
        in: query
        description: Number of messages to return
        schema:
          type: integer
      responses:
        '200':
          description: DLQ messages
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DlqListResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /dlq/{dlqId}:
    get:
      operationId: getDlqMessage
      summary: Get a dead letter queue message
      description: Retrieve a specific DLQ message by its DLQ ID.
      tags:
      - Dead Letter Queue
      parameters:
      - name: dlqId
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: DLQ message details
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DlqMessage'
        '404':
          $ref: '#/components/responses/NotFound'
    delete:
      operationId: deleteDlqMessage
      summary: Delete a dead letter queue message
      description: Permanently delete a message from the dead letter queue.
      tags:
      - Dead Letter Queue
      parameters:
      - name: dlqId
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: DLQ message deleted
        '404':
          $ref: '#/components/responses/NotFound'
  /dlq/{dlqId}/republish:
    post:
      operationId: republishDlqMessage
      summary: Republish a dead letter queue message
      description: Republish a dead letter queue message for redelivery to its original destination.
      tags:
      - Dead Letter Queue
      parameters:
      - name: dlqId
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Message republished
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PublishResponse'
        '404':
          $ref: '#/components/responses/NotFound'
components:
  schemas:
    DlqListResponse:
      type: object
      properties:
        cursor:
          type: string
          description: Pagination cursor for the next page
        messages:
          type: array
          items:
            $ref: '#/components/schemas/DlqMessage'
    ErrorResponse:
      type: object
      properties:
        error:
          type: string
          description: Human-readable error message
    PublishResponse:
      type: object
      properties:
        messageId:
          type: string
          description: Unique identifier for the published message
          example: msg_2XavMmRcJHJf7HkNtNqjfVf8uQe
        url:
          type: string
          description: Destination URL the message will be delivered to
          example: https://example.com/webhook
    DlqMessage:
      type: object
      properties:
        dlqId:
          type: string
          description: Dead letter queue message identifier
        messageId:
          type: string
          description: Original message identifier
        destination:
          type: string
          description: Original delivery destination URL
        createdAt:
          type: integer
          description: Unix timestamp when message entered DLQ
        retried:
          type: integer
          description: Number of delivery attempts made
        maxRetries:
          type: integer
          description: Maximum retries configured for the original message
        body:
          type: string
          description: Base64-encoded message body
        header:
          type: object
          additionalProperties:
            type: array
            items:
              type: string
          description: Headers from the original message
        responseStatus:
          type: integer
          description: Last HTTP response status code received from destination
        responseBody:
          type: string
          description: Last HTTP response body received from destination
  responses:
    Unauthorized:
      description: Missing or invalid authentication token
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
    NotFound:
      description: Resource not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      description: Bearer token obtained from the Upstash console at https://console.upstash.com/qstash. Alternatively, pass as query parameter `qstash_token`.
externalDocs:
  description: QStash Documentation
  url: https://upstash.com/docs/qstash/overall/getstarted