n8n Webhook: Extract JSON from Web Pages Using Gaffa

Extract structured JSON from any web page—via a secured n8n webhook using Gaffa

This n8n workflow exposes a secured Webhook that accepts a page URL plus a fields schema, then uses Gaffa to load the page and return clean, structured JSON for exactly the fields you request (with caching support and clear error responses).

What this workflow does

• Receives a POST request on a webhook endpoint protected by Header Auth.
• Validates the JSON body (expects url, optional selector, and a non-empty fields schema with supported types). If validation fails, it returns HTTP 400 with an error message.
• Builds a Gaffa parse_json extraction request using your requested fields.
• Uses configurable caching via max_cache_age to allow cached extraction results.
• Returns extracted JSON with HTTP 200 and a from_cache flag when successful.
• If Gaffa cannot extract the data, it returns HTTP 502 with Gaffa’s error message.

Use cases

• SaaS data ingestion: Turn selected fields from public or internal web pages into structured JSON for downstream automation.
• Lead enrichment: Extract specific attributes from a profile page using a provided selector and schema.
• Ops and reporting: Automate extraction of recurring page elements for dashboards or audits.

Technical details

• Requires the community node @gaffa-dev/n8n-nodes-gaffa in your n8n instance.
• Uses a Gaffa API credential (API key) and sends a parse_json request to render and extract fields.
• Implements Header Auth for webhook security, plus if, set, code, and respond to webhook to validate input and return 400/200/502 responses.

How to use: Create a Gaffa account, generate an API key, configure it in n8n, then POST application/json to the workflow’s production webhook with url, fields, and optional selector.