Status: [UNTESTED]

Endpoints found:
http://localhost:8080/api/admin/ingest
http://localhost:8080/api/admin/status
http://localhost:8080/api/rag/ask?question=Which+pilgrimage+site+has+a+free+community+kitchen

Source: https://github.com/debdip03/langchain4j-rag-embeddings-poc

# langchain4j-rag-embeddings-poc

A Retrieval-Augmented Generation (RAG) pipeline built with **Langchain4j** and **Spring Boot**, using **Ollama** as a completely free, local LLM and embedding-model provider — no API key, no billing, no rate limits.

## Why Ollama for the "free LLM"

- Runs entirely on your machine — no signup, no cost, no usage caps.
- Langchain4j has first-class support (`langchain4j-ollama`) for both chat and embedding models.
- Swappable later: the config class is the only place you'd touch to point at a hosted provider (e.g. Groq, Gemini free tier) instead.

## Prerequisites

1. **Java 21** and **Maven 3.9+**
2. **Ollama** installed — https://ollama.com/download
3. Pull the two models this app uses:
   ```bash
   ollama pull llama3.1
   ollama pull nomic-embed-text
   ```
4. Make sure Ollama is running (it starts a local server on `http://localhost:11434` automatically after install, or run `ollama serve`).

## Project structure

```
langchain4j-rag-embeddings-poc
├── src/main/java/com/gen/ai
│   ├── RagEmbeddingsApplication.java        # Spring Boot entrypoint
│   ├── config/RagEmbeddingsConfig.java      # Ollama chat/embedding model + vector store beans
│   ├── controller/
│   │   ├── RagEmbeddedChunksRetrievalController.java   # GET /api/rag/ask
│   │   └── RagEmbeddingsAdminController.java           # POST /api/admin/ingest, GET /api/admin/status
│   ├── exception/RagEmbeddingsControllerAdvice.java     # centralized error handling
│   ├── model/
│   │   ├── RagRetrievalResponse.java
│   │   └── RetrievedChunk.java
│   └── service/
│       ├── RagEmbeddedChunksRetrievalService.java  # embed query -> search -> prompt -> LLM answer
│       └── RagEmbeddingsAdminService.java          # load/split/embed/store source documents
├── src/main/resources/application.yml
├── pilgrimage-tourist-sites/                # sample so