A reusable and production-ready n8n workflow that secures public webhooks using Bearer Token authentication and dynamic request validation. ✨ What It Does Verifies Bearer Token** Compares the Authorization header with a configured secret token. Validates Required Fields** Checks that all expected fields are present in the incoming request body. Returns Standardized JSON Responses** 401 Unauthorized if token is missing or invalid 400 Bad Request if required fields are missing 200 OK with a custom success payload 👤 Who It’s For Developers exposing n8n workflows as APIs No-code/low-code builders integrating with external forms or tools Anyone needing simple authentication and validation on incoming webhooks 💡 Why Use It 🔒 Secure: Prevents unauthorized access to your public workflows 🧼 Clean: Centralized configuration for token and required fields ⚙️ Flexible: Easy to extend and customize for any use case 🛠 Setup Instructions Configure Values in the Configuration Node Set your secret token: config.bearerToken = YOUR_TOKEN Define required request fields by key: Example: config.requiredFields.message = true; config.requiredFields.email = true; ✅ Only the keys matter – values can be
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See all General Automation→Poll and download received invoice PDFs with KSeF Gateway to disk storage
Quick overview This workflow runs every 20 minutes to poll a self-hosted KSeF Gateway for newly received KSeF invoices, maintains a cursor checkpoint in n8n static data, downloads each new invoice PDF via the gateway API, and saves the files to local disk. How it works Runs every 20 minutes on a schedule. Reads the last successful polling checkpoint from the workflow’s static data and calls the KSeF Gateway /ksef/invoices/received/new endpoint with the since cursor. If the gateway response is unsuccessful, records the error details for alerting and leaves the checkpoint unchanged so the next run retries the same window. If the response is successful, stores the returned nextSince value as the new checkpoint. If new invoices are returned, processes each invoice summary individually. Downloads each invoice PDF from the KSeF Gateway /ksef/invoice/{ksefNumber}/pdf endpoint and saves it to the configured local folder. Outputs invoice metadata (number, seller, amount, and saved file path) as a placeholder where you can plug in notifications (Slack, email, or Discord). Setup Deploy and configure a self-hosted KSeF Gateway (https://github.com/jurczykpawel/ksef-gateway) with a token or cert
Create KSeF invoices from completed Sellf purchases via KSeF Gateway
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Send signed WooCommerce orders to KSeF via a self-hosted KSeF Gateway
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