Google Sheets

Install the jsontoimg Apps Script add-on (clasp). Map header columns to named layers, render selected rows, and write the signed GET /api/v1/img/{template} URL back to a URL column and/or an in-cell image. Same /api/v1 contract as REST and n8n.

This add-on is button-driven. It does not run on cell edit. For that, use n8n or HTTP. Workspace Marketplace publishing is not required.

Install

1. Open the spreadsheet. Optionally open Extensions → Apps Script so a bound project exists.
2. Install the CLI: npm install -g @google/clasp
3. In j2i-integrations/google-sheets: npm install, npm run build, then clasp create --type sheets --title jsontoimg --rootDir dist (or copy .clasp.json.example to .clasp.json and set scriptId).
4. npm run push — reload the sheet, then jsontoimg → Open. Authorize the script on first run.

Credentials

1. Create an API key under Integrations → API keys.
2. In the sidebar, open Settings.
3. Paste the jsontoimg API key. Leave Base URL blank for https://app.jsontoimg.com (a trailing /api/v1 is stripped).
4. Click Test connection.

The key is stored in UserProperties for that Google account. Template, format, and column mapping are stored in DocumentProperties on the spreadsheet. Use a dedicated key you can revoke.

First render

1. Pick a header row, template, and format.
2. Map each named layer to a column header (text layers stringify; image layers take an http(s) cell).
3. Pick a URL column and/or image column for write-back.
4. Select data rows (cap 50; the header row is skipped) → Render selected.

Each row mints POST /api/v1/img/sign, warms the signed GET /api/v1/img/{template} URL (retries HTTP 503), writes that URL, then for raster formats inserts an in-cell image (SpreadsheetApp.newCellImage). PDF is URL-only.

Limits

• 50 selected rows per run
• Apps Script cannot subscribe to cell edits; use n8n or HTTP for automations
• In-cell images are raster only (png / jpg / webp / avif)