{"product_id":"secure-invoice-ingestion-with-openai-slack-erp-webhooks","title":"Secure Invoice Ingestion with OpenAI, Slack \u0026 ERP Webhooks","description":"\u003ch3\u003eSecure Invoice Ingestion with OpenAI, Slack \u0026amp; ERP Webhooks\u003c\/h3\u003e\n\u003cp\u003eTurn invoice PDFs into structured data automatically: this n8n workflow accepts documents via webhook, extracts invoice fields with OpenAI, auto-validates them, and posts approved invoices to your ERP—while sending any exceptions to Slack for human review before anything touches your system.\u003c\/p\u003e\n\n\u003ch3\u003eWhat this workflow does\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReceives invoice PDFs\u003c\/strong\u003e via a POST request to the \u003ccode\u003e\/idp-ingest\u003c\/code\u003e webhook, accepting the invoice as a \u003cem\u003ebinary file\u003c\/em\u003e (or using \u003ccode\u003ebody.fileContent\u003c\/code\u003e where applicable).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eValidates intake\u003c\/strong\u003e by checking file type and size, and honoring an optional malware-scan status. It then creates correlation and document metadata for downstream processing.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDe-duplicates and routes outcomes\u003c\/strong\u003e using demo logic: duplicates and invalid intakes are routed to an exception path instead of being processed further.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eExtracts invoice data from PDFs\u003c\/strong\u003e by converting\/reading PDF text and sending OCR text to \u003cstrong\u003eOpenAI\u003c\/strong\u003e to return a structured invoice JSON.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eValidates invoice quality\u003c\/strong\u003e against a validation policy: required fields, non-negative amounts, presence of line items, and confidence thresholds.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAuto-approves or escalates\u003c\/strong\u003e: valid invoices are approved; violations trigger an exception.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSlack-based manual review for exceptions\u003c\/strong\u003e: the workflow posts a detailed message to \u003cstrong\u003eSlack\u003c\/strong\u003e, waits for a reviewer’s webhook decision, and routes approved vs. rejected outcomes.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePosts to your ERP\u003c\/strong\u003e for approved invoices via HTTP using an \u003ccode\u003eIdempotency-Key\u003c\/code\u003e header, then generates a sanitized audit log. Rejected\/duplicate items are closed without ERP posting.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eUse cases\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eAutomate AP intake by converting invoice PDFs into ERP-ready JSON with OpenAI.\u003c\/li\u003e\n  \u003cli\u003eAdd a human-in-the-loop review step for low-confidence or invalid invoices using Slack.\u003c\/li\u003e\n  \u003cli\u003ePrevent duplicate processing with idempotent ERP posting and correlation metadata.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical details\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003en8n nodes\/blocks: \u003cstrong\u003eWebhook\u003c\/strong\u003e, \u003cstrong\u003eCode\u003c\/strong\u003e, \u003cstrong\u003eSwitch\u003c\/strong\u003e, \u003cstrong\u003eWait\u003c\/strong\u003e, \u003cstrong\u003eSlack\u003c\/strong\u003e, and supporting nodes (including \u003cstrong\u003eSticky Note\u003c\/strong\u003e for clarity).\u003c\/li\u003e\n  \u003cli\u003eERP integration: \u003cstrong\u003eHTTP\u003c\/strong\u003e posting to an ERP endpoint with \u003cstrong\u003eIdempotency-Key\u003c\/strong\u003e.\u003c\/li\u003e\n  \u003cli\u003eOperational flow: exception handling via Slack + webhook-based reviewer decision.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eSetup\u003c\/h3\u003e\n\u003cp\u003eConfigure the \u003ccode\u003e\/idp-ingest\u003c\/code\u003e webhook in your source system to send a \u003ccode\u003edocument\u003c\/code\u003e binary file (or provide \u003ccode\u003ebody.fileContent\u003c\/code\u003e for the included Convert to File step), and use the generated resume webhook URL for the reviewer decision.\u003c\/p\u003e","brand":"N8N Commerce","offers":[{"title":"Default Title","offer_id":45761014923443,"sku":"N8N-17806","price":14.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0749\/6279\/6723\/files\/GB0kDGJxUHt3cYpF99a6Q_0GNiUNh0.png?v=1785921558","url":"https:\/\/buyflowscripts.com\/products\/secure-invoice-ingestion-with-openai-slack-erp-webhooks","provider":"N8N Commerce","version":"1.0","type":"link"}