Customiser fonts

Attach a font file

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Takes the TrueType file of a staged upload and makes it this font's typeface, returning the font with font_file.has_font_file true and a live ttf_url. Requires customisers:write and an Idempotency-Key.

PUT/api/v3/customisers/{customiser_id}/fonts/{font_id}/file

Attach a font file

Takes the TrueType file of a staged upload and makes it this font's typeface, returning the font with `font_file.has_font_file` true and a live `ttf_url`. Requires `customisers:write` and an `Idempotency-Key`. Create the upload first with `POST /api/v3/uploads` using purpose `font_ttf`, send the bytes to the presigned target it returns, then send that upload's id here. The upload is single use: attaching it a second time answers 409, and a replacement typeface needs a new upload. The bytes are verified here, not at create: the object must exist, be within the purpose's cap, start with TrueType magic, and carry a table directory a renderer can read. A file that fails leaves the upload `rejected` with the failure's code, and attaching it again replays that code — so fix the file and create a new upload rather than retrying. Sending this to a font that already has a typeface replaces it. The previous file is deleted once the new one is committed, so any URL published for it stops resolving. The attach mints a fresh server-owned `font_file.family_name`, clears the customiser's cached storefront configuration, and runs the advisory language sync. It never regenerates Shopify products, product images, or the product cache.

Attach a font file

Overview

Create the upload first with POST/api/v3/uploads using purpose font_ttf, send the bytes to the presigned target it returns, then send that upload's id here. The upload is single use: attaching it a second time answers 409, and a replacement typeface needs a new upload. The bytes are verified here, not at create: the object must exist, be within the purpose's cap, start with TrueType magic, and carry a table directory a renderer can read. A file that fails leaves the upload rejected with the failure's code, and attaching it again replays that code — so fix the file and create a new upload rather than retrying. Sending this to a font that already has a typeface replaces it. The previous file is deleted once the new one is committed, so any URL published for it stops resolving. The attach mints a fresh server-owned font_file.family_name, clears the customiser's cached storefront configuration, and runs the advisory language sync. It never regenerates Shopify products, product images, or the product cache.

Authorisation

Bearer token required. Include it in the Authorization header.

Required scope: customisers:write

Path parameters

customiser_idstringpathrequired

The customiser id.

Example: 1

font_idstringpathrequired

The font id.

Example: 11

Request body

upload_idstringbody

Request body example

{
  "upload_id": "upl_9f2c4b7ad13e6058ba41cd4201"
}

Attach a font file

curl https://web.signcustomiser.com/api/v3/customisers/1/fonts/11/file \
  --request PUT \
  --header 'Accept: application/json' \
  --header 'Authorization: Bearer YOUR_API_TOKEN' \
  --header 'Content-Type: application/json' \
  --data '{
  "upload_id": "upl_9f2c4b7ad13e6058ba41cd4201"
}'

{
  "data": {
    "object": "font",
    "id": 11,
    "customiser_id": 42,
    "name": "Signature Script",
    "line_height": null,
    "uses_default_line_height": true,
    "stencil_safe": false,
    "min_height_smallest_letter_cm": null,
    "min_height_uppercase_letter_cm": null,
    "font_tier_id": 7,
    "length_pricing_id": null,
    "minimum_size_id": null,
    "minimum_legacy_fixed_height_size_id": null,
    "sort_order": 1,
    "font_file": {
      "has_font_file": true,
      "family_name": "kx7q2m9v4t1b8n6c3z5j0h2w4r7y1p6d",
      "ttf_url": "https://cdn.example.com/files/2f1c9c0e-6a7b-4c1d-8e2f-3a4b5c6d7e8f.ttf"
    },
    "created_at": "2026-08-13T00:00:00Z",
    "updated_at": "2026-08-13T00:05:00Z"
  },
  "links": {
    "self": "https://web.signcustomiser.com/api/v3/customisers/42/fonts/11/file",
    "documentation": "https://www.signcustomiser.com/help/api/"
  },
  "meta": {
    "api_version": "v3",
    "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
  }
}

{
  "type": "https://www.signcustomiser.com/help/api/problems/missing_idempotency_key",
  "title": "Missing idempotency key",
  "status": 400,
  "code": "missing_idempotency_key",
  "detail": "Provide an Idempotency-Key header for this write.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}

{
  "type": "https://www.signcustomiser.com/help/api/problems/missing_api_key",
  "title": "Missing API key",
  "status": 401,
  "code": "missing_api_key",
  "detail": "Provide a store API key as a bearer token.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}

{
  "type": "https://www.signcustomiser.com/help/api/problems/insufficient_scope",
  "title": "Insufficient scope",
  "status": 403,
  "code": "insufficient_scope",
  "detail": "This operation requires the customisers:write scope.",
  "required_scopes": [
    "customisers:write"
  ],
  "granted_scopes": [
    "customisers:read"
  ],
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}

{
  "type": "https://www.signcustomiser.com/help/api/problems/resource_not_found",
  "title": "Resource not found",
  "status": 404,
  "code": "resource_not_found",
  "detail": "The requested resource does not exist or does not belong to the authenticated store.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}

{
  "type": "https://www.signcustomiser.com/help/api/problems/upload_already_attached",
  "title": "Upload already attached",
  "status": 409,
  "code": "upload_already_attached",
  "detail": "This upload has already been attached to a file slot. Each upload is single use: create a new upload for each assignment.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}

{
  "type": "https://www.signcustomiser.com/help/api/problems/upload_content_type_mismatch",
  "title": "Upload content type mismatch",
  "status": 422,
  "code": "upload_content_type_mismatch",
  "detail": "The uploaded bytes are not font/ttf. The declared content type must match the file you send; upload the correct file under a new upload.",
  "errors": [
    {
      "pointer": "/upload_id",
      "code": "upload_content_type_mismatch",
      "detail": "The stored object is not font/ttf."
    }
  ],
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}

{
  "type": "https://www.signcustomiser.com/help/api/problems/rate_limited",
  "title": "Too many requests",
  "status": 429,
  "code": "rate_limited",
  "detail": "You have exceeded the request limit for this API key.",
  "retry_after": 37,
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}