Next.js RAG Chat Webhook Workflow: OpenAI, Pinecone, Redis

Secure Next.js RAG Chat via Webhook—OpenAI + Pinecone + Redis (with optional ISR revalidation)

Deploy an n8n automation workflow that exposes a header-authenticated webhook API for your Next.js app to run a Retrieval-Augmented Generation (RAG) chat agent using OpenAI, Pinecone, and Redis—with structured JSON answers, citations, and optional ISR refresh callbacks when grounded content changes.

What this workflow does

• Receives a POST webhook from a Next.js Server Action or Route Handler on a secure endpoint (using Header Auth via x-api-key).
• Validates inputs (e.g., query, conversationId, tenantId, and an allowed namespace) and returns a structured 400 response when checks fail.
• Speeds up repeated requests by generating a deterministic cache key and returning cached results from Redis for identical queries.
• On cache miss, creates OpenAI embeddings and retrieves top passages from a Pinecone index scoped to the request namespace.
• Uses an OpenAI-powered agent with conversation window memory and a vector-search tool to output structured JSON containing citations and a groundedness/confidence score.
• Normalizes and persists results: validates the JSON output, stores it in Redis with a TTL, and logs each conversation turn to Postgres.
• Responds to Next.js with the final payload, and if the answer is grounded, triggers a non-blocking callback to /api/revalidate to refresh an ISR tag for that namespace.

Use cases

• SaaS chat experiences that answer questions from tenant-scoped knowledge using Pinecone, with Redis caching for low latency.
• Next.js RAG endpoints that return cited, confidence-scored JSON results and automatically refresh ISR when grounded content warrants it.
• Teams needing audit-friendly conversation logging via Postgres.

Technical details

• Integrations: OpenAI, Pinecone, Redis, Postgres.
• n8n nodes/logic: webhook (header-authenticated), if, set, code, no op, redis.
• Requires credentials for OpenAI, Redis, and Postgres and webhook Header Auth via x-api-key.