> ## Documentation Index
> Fetch the complete documentation index at: https://developer.dromo.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Resume a session (re-issue hydrationId)

> Issues a fresh `hydrationId` for an existing session. Call this server-side when the user returns after their previous token has expired. The new token must belong to the same org as the session.



## OpenAPI

````yaml /api-reference/sessions-openapi.json post /{sessionId}/auth/
openapi: 3.1.0
info:
  title: Dromo Sessions API
  description: APIs for managing partial-import save/restore sessions.
  version: '1.0'
servers:
  - url: https://app.dromo.io/api/widget/session/v2
security:
  - backend_license_key: []
tags:
  - name: sessions
    description: Managing partial-import save/restore sessions
paths:
  /{sessionId}/auth/:
    post:
      tags:
        - sessions
      summary: Resume a session (re-issue hydrationId)
      description: >-
        Issues a fresh `hydrationId` for an existing session. Call this
        server-side when the user returns after their previous token has
        expired. The new token must belong to the same org as the session.
      operationId: resumeSession
      parameters:
        - name: sessionId
          in: path
          required: true
          description: >-
            UUID of the session to resume. Returned as `sessionId` when the
            session was created. Returns 404 if the session doesn't exist or
            hasn't been saved within 7 days.
          schema:
            type: string
            format: uuid
            example: 1b6acf28-8748-4120-8d7a-4b7846d5e487
      requestBody:
        required: false
        content:
          application/json:
            schema:
              type: object
              properties:
                expires_in:
                  type: integer
                  example: 3600
                  description: New token TTL in seconds. Defaults to 21600 (6 hours).
      responses:
        '200':
          description: Fresh hydrationId issued
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TokenResponse'
        '404':
          description: Session not found or expired (>7 days since last save)
components:
  schemas:
    TokenResponse:
      type: object
      properties:
        hydrationId:
          type: string
          example: <new-signed-token>
          description: The new access token. Pass this to the widget to resume the session.
        expiresIn:
          type: integer
          example: 21600
          description: Seconds until the new hydrationId expires.
  securitySchemes:
    backend_license_key:
      type: apiKey
      name: X-DROMO-LICENSE-KEY
      in: header
      description: >-
        Your **backend** license key (`is_for_backend_api=True`) from the [Dromo
        Dashboard](https://dashboard.dromo.io/). Never expose this client-side.

````