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

# Start data loading

> Requires session status `UPLOADING`, finished background preparation of uploaded packages, and at least one uploaded entity. Starts loading of the data collected in the session.



## OpenAPI

````yaml /connector-api/openapi.json post /uploading/{upload_uuid}/start-upload
openapi: 3.1.0
info:
  title: Connector API
  version: 0.1.0
servers:
  - url: https://connector-api.datawiz.io/api/v1
    description: Connector API
security: []
paths:
  /uploading/{upload_uuid}/start-upload:
    post:
      tags:
        - Uploading
      summary: Start data loading
      description: >-
        Requires session status `UPLOADING`, finished background preparation of
        uploaded packages, and at least one uploaded entity. Starts loading of
        the data collected in the session.
      operationId: start_upload_api_v1_uploading__upload_uuid__start_upload_post
      parameters:
        - name: upload_uuid
          in: path
          required: true
          schema:
            type: string
            title: Upload Uuid
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/WorkflowDateRange'
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/StartUploadResponse'
        '400':
          description: >-
            Session not initialized; date_from earlier than client minimum; or
            no entities uploaded. Examples: `{"detail": "Upload session not
            initialized"}`, `{"detail": "date_from cannot be earlier than
            2020-01-01"}`, `{"detail": "No entities were uploaded in this
            session"}`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
        '401':
          description: >-
            Invalid or missing access token. Body: `{"detail": "User not
            authenticated"}`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
        '403':
          description: >-
            upload_uuid does not match the active session. Body: `{"detail":
            "Invalid upload UUID"}`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
        '409':
          description: >-
            Wrong session status (structured `detail` with expected/actual),
            packages still being prepared (`{"detail": "Upload tasks are still
            in progress"}`), or data loading rejected (string `detail`).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
        '413':
          description: >-
            Request body exceeds size limit (32 MB for ingest, 1 MB for other
            requests).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
        '422':
          description: >-
            Invalid date range in request body (Pydantic validation array in
            `detail`) or business-rule violations such as date_to >= today.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
        '500':
          description: >-
            Internal error while starting data loading. Body: `{"detail":
            "<message>"}`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
        '502':
          description: >-
            Temporary failure while starting data loading. Body: `{"detail":
            "Failed to start data loading"}`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
        '503':
          description: Rate limit or concurrent connection limit exceeded.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDetailResponse'
      security:
        - Authorization: []
          Client-Id: []
components:
  schemas:
    WorkflowDateRange:
      properties:
        date_from:
          type: string
          format: date
          title: Date From
          description: Start date of the data loading window (inclusive).
        date_to:
          type: string
          format: date
          title: Date To
          description: >-
            End date of the data loading window (inclusive). Must be before
            today.
      type: object
      required:
        - date_from
        - date_to
      title: WorkflowDateRange
    StartUploadResponse:
      properties:
        status:
          anyOf:
            - type: string
            - type: 'null'
          title: Status
          description: Data loading start response status.
      additionalProperties: true
      type: object
      title: StartUploadResponse
    ErrorDetailResponse:
      properties:
        detail:
          anyOf:
            - type: string
            - additionalProperties: true
              type: object
          title: Detail
          description: Error message or structured error object.
      type: object
      required:
        - detail
      title: ErrorDetailResponse
  securitySchemes:
    Authorization:
      type: apiKey
      in: header
      name: Authorization
    Client-Id:
      type: apiKey
      in: header
      name: Client-Id

````

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