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

# Initiate a signed-URL CAD model upload

> Return a signed URL to PUT a CAD model to (up to 100 MB).

PUT the file bytes to ``signed_url`` with the returned ``content_type``, then
call ``confirm-upload`` with the same ``file_name`` and the returned
``upload_id`` to attach it.



## OpenAPI

````yaml https://api.ionworks.com/openapi.json post /cell_specifications/{cell_spec_id}/cad/initiate-upload
openapi: 3.1.0
info:
  title: FastAPI
  version: 0.1.0
servers:
  - url: https://api.ionworks.com
    description: Production
security: []
paths:
  /cell_specifications/{cell_spec_id}/cad/initiate-upload:
    post:
      tags:
        - Cell Specifications
      summary: Initiate a signed-URL CAD model upload
      description: >-
        Return a signed URL to PUT a CAD model to (up to 100 MB).


        PUT the file bytes to ``signed_url`` with the returned ``content_type``,
        then

        call ``confirm-upload`` with the same ``file_name`` and the returned

        ``upload_id`` to attach it.
      operationId: >-
        initiate_cell_specification_cad_upload_cell_specifications__cell_spec_id__cad_initiate_upload_post
      parameters:
        - name: cell_spec_id
          in: path
          required: true
          schema:
            type: string
            format: uuid
            title: Cell Spec Id
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CadUploadRequest'
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CadUploadTarget'
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
components:
  schemas:
    CadUploadRequest:
      properties:
        file_name:
          type: string
          title: File Name
          description: >-
            Filename of the model, e.g. 'cell.step'. Its extension selects the
            format: .step, .stp, .iges, .igs, .stl, .obj, .ply, .glb, or .off.
      type: object
      required:
        - file_name
      title: CadUploadRequest
      description: Identifies the CAD file being uploaded.
    CadUploadTarget:
      properties:
        upload_id:
          type: string
          title: Upload Id
          description: Identifies this upload; pass it back to confirm-upload.
        path:
          type: string
          title: Path
          description: Storage path the model is written to.
        signed_url:
          type: string
          title: Signed Url
          description: Signed URL to PUT the file to.
        token:
          type: string
          title: Token
          description: Upload token embedded in the signed URL.
        content_type:
          type: string
          title: Content Type
          description: Content-Type header the PUT must carry.
      type: object
      required:
        - upload_id
        - path
        - signed_url
        - token
        - content_type
      title: CadUploadTarget
      description: Where the client PUTs a CAD model.
    HTTPValidationError:
      properties:
        detail:
          items:
            $ref: '#/components/schemas/ValidationError'
          type: array
          title: Detail
      type: object
      title: HTTPValidationError
    ValidationError:
      properties:
        loc:
          items:
            anyOf:
              - type: string
              - type: integer
          type: array
          title: Location
        msg:
          type: string
          title: Message
        type:
          type: string
          title: Error Type
        input:
          title: Input
        ctx:
          type: object
          title: Context
      type: object
      required:
        - loc
        - msg
        - type
      title: ValidationError

````

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