The Reusable n8n Module Every Document Workflow Needs 🔥
Built 15 document workflows. All needed same error handling. Copying logic between workflows was tedious. One bug meant updating 15 workflows. Created reusable error module. Now every workflow more robust with zero duplicated code. THE MODULE (5 NODES): Function Node → catches errors from document processing IF Node → checks error type (parsing/API/validation/timeout) Switch Node → routes to appropriate recovery Slack Node → notifies with error details + document context Google Sheets → logs failed documents for bulk reprocessing THE ERROR CATEGORIES: Parsing failures: Document unreadable (corrupted, unsupported format) → Manual processing queue, immediate notification Extraction failures: Low confidence data extraction → Human review queue with document preview API failures: External service timeout (QuickBooks, Airtable) → Retry with exponential backoff, queue if still fails Validation failures: Data fails business rules (negative amounts, future dates) → Flag for review with specific errors highlighted WHY THIS MATTERS: Before module: Each workflow handled errors differently. Some failed silently. Documents disappeared. Clients complained. After module: Consistent handling everywhere. Every failure logged. Every error recoverable. Zero lost documents. THE IMPLEMENTATION: Built 5-node module once. Saved as workflow snippet. When building new workflow, import module, connect to error output. Done. Time: 2 hours to build initially. Saves 30 minutes per new workflow. REAL RECOVERY: QuickBooks API down 3 hours. 240 invoices failed. Without module: Manual reprocessing nightmare. With module: All 240 logged automatically. Slack notified once. When API returned, triggered bulk reprocess. All posted automatically. THE UNEXPECTED BENEFIT: Error logs became debugging data. Saw pattern: "80% of reviews are Vendor X invoices." Investigated. Vendor X uses non-standard format. Added specific handling. Review rate dropped to 5%. CURRENT STATE: 15 workflows using same module