fixed a few bugs related to vector embedding + added additional end to end documentation to showcase local and external embedders step-by-step + added example mock embedder python script

docs/local_embedder_full_example.md

@@ -0,0 +1,988 @@
+# HeroDB Embedding Models: Complete Tutorial
+
+This tutorial demonstrates how to use embedding models with HeroDB for vector search, covering both local self-hosted models and OpenAI's API.
+
+## Table of Contents
+- [Prerequisites](#prerequisites)
+- [Scenario 1: Local Embedding Model](#scenario-1-local-embedding-model-testing)
+- [Scenario 2: OpenAI API](#scenario-2-openai-api)
+- [Scenario 3: Deterministic Test Embedder](#scenario-3-deterministic-test-embedder-no-network)
+- [Troubleshooting](#troubleshooting)
+
+---
+
+## Prerequisites
+
+### Start HeroDB Server
+
+Build and start HeroDB with RPC enabled:
+
+```bash
+cargo build --release
+./target/release/herodb --dir ./data --admin-secret my-admin-secret --enable-rpc --rpc-port 8080
+```
+
+This starts:
+- Redis-compatible server on port 6379
+- JSON-RPC server on port 8080
+
+### Client Tools
+
+For Redis-like commands:
+```bash
+redis-cli -p 6379
+```
+
+For JSON-RPC calls, use `curl`:
+```bash
+curl -X POST http://localhost:8080 \
+  -H "Content-Type: application/json" \
+  -d '{"jsonrpc":"2.0","id":1,"method":"herodb_METHOD","params":[...]}'
+```
+
+---
+
+## Scenario 1: Local Embedding Model (Testing)
+
+Run your own embedding service locally for development, testing, or privacy.
+
+### Option A: Python Mock Server (Simplest)
+
+This creates a minimal OpenAI-compatible embedding server for testing.
+
+**1. Create `mock_embedder.py`:**
+
+```python
+from flask import Flask, request, jsonify
+import numpy as np
+
+app = Flask(__name__)
+
+@app.route('/v1/embeddings', methods=['POST'])
+def embeddings():
+    """OpenAI-compatible embeddings endpoint"""
+    data = request.json
+    inputs = data.get('input', [])
+    
+    # Handle both single string and array
+    if isinstance(inputs, str):
+        inputs = [inputs]
+    
+    # Generate deterministic 768-dim embeddings (hash-based)
+    embeddings = []
+    for text in inputs:
+        # Simple hash to vector (deterministic)
+        vec = np.zeros(768)
+        for i, char in enumerate(text[:768]):
+            vec[i % 768] += ord(char) / 255.0
+        
+        # L2 normalize
+        norm = np.linalg.norm(vec)
+        if norm > 0:
+            vec = vec / norm
+        
+        embeddings.append(vec.tolist())
+    
+    return jsonify({
+        "data": [{"embedding": emb, "index": i} for i, emb in enumerate(embeddings)],
+        "model": data.get('model', 'mock-local'),
+        "usage": {"total_tokens": sum(len(t) for t in inputs)}
+    })
+
+if __name__ == '__main__':
+    print("Starting mock embedding server on http://127.0.0.1:8081")
+    app.run(host='127.0.0.1', port=8081, debug=False)
+```
+
+**2. Install dependencies and run:**
+
+```bash
+pip install flask numpy
+python mock_embedder.py
+```
+
+Output: `Starting mock embedding server on http://127.0.0.1:8081`
+
+**3. Test the server (optional):**
+
+```bash
+curl -X POST http://127.0.0.1:8081/v1/embeddings \
+  -H "Content-Type: application/json" \
+  -d '{"input":["hello world"],"model":"test"}'
+```
+
+You should see a JSON response with a 768-dimensional embedding.
+
+### End-to-End Example with Local Model
+
+**Step 1: Create a Lance database**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "herodb_createDatabase",
+  "params": [
+    "Lance",
+    { "name": "local-vectors", "storage_path": null, "max_size": null, "redis_version": null },
+    null
+  ]
+}
+```
+
+Expected response:
+```json
+{"jsonrpc":"2.0","id":1,"result":1}
+```
+
+The database ID is `1`.
+
+**Step 2: Configure embedding for the dataset**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 2,
+  "method": "herodb_lanceSetEmbeddingConfig",
+  "params": [
+    1,
+    "products",
+    {
+      "provider": "openai",
+      "model": "mock-local",
+      "dim": 768,
+      "endpoint": "http://127.0.0.1:8081/v1/embeddings",
+      "headers": {
+        "Authorization": "Bearer dummy"
+      },
+      "timeout_ms": 30000
+    }
+  ]
+}
+```
+
+Redis-like:
+```bash
+redis-cli -p 6379
+SELECT 1
+LANCE.EMBEDDING CONFIG SET products PROVIDER openai MODEL mock-local DIM 768 ENDPOINT http://127.0.0.1:8081/v1/embeddings HEADER Authorization "Bearer dummy" TIMEOUTMS 30000
+```
+
+Expected response:
+```json
+{"jsonrpc":"2.0","id":2,"result":true}
+```
+
+**Step 3: Verify configuration**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 3,
+  "method": "herodb_lanceGetEmbeddingConfig",
+  "params": [1, "products"]
+}
+```
+
+Redis-like:
+```bash
+LANCE.EMBEDDING CONFIG GET products
+```
+
+Expected: Returns your configuration with provider, model, dim, endpoint, etc.
+
+**Step 4: Insert product data**
+
+JSON-RPC (item 1):
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 4,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "products",
+    "item-1",
+    "Waterproof hiking boots with ankle support and aggressive tread",
+    { "brand": "TrailMax", "category": "footwear", "price": "129.99" }
+  ]
+}
+```
+
+Redis-like:
+```bash
+LANCE.STORE products ID item-1 TEXT "Waterproof hiking boots with ankle support and aggressive tread" META brand TrailMax category footwear price 129.99
+```
+
+JSON-RPC (item 2):
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 5,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "products",
+    "item-2",
+    "Lightweight running shoes with breathable mesh upper",
+    { "brand": "SpeedFit", "category": "footwear", "price": "89.99" }
+  ]
+}
+```
+
+JSON-RPC (item 3):
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 6,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "products",
+    "item-3",
+    "Insulated winter jacket with removable hood and multiple pockets",
+    { "brand": "WarmTech", "category": "outerwear", "price": "199.99" }
+  ]
+}
+```
+
+JSON-RPC (item 4):
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 7,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "products",
+    "item-4",
+    "Camping tent for 4 people with waterproof rainfly",
+    { "brand": "OutdoorPro", "category": "camping", "price": "249.99" }
+  ]
+}
+```
+
+Expected response for each: `{"jsonrpc":"2.0","id":N,"result":true}`
+
+**Step 5: Search by text query**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 8,
+  "method": "herodb_lanceSearchText",
+  "params": [
+    1,
+    "products",
+    "boots for hiking in wet conditions",
+    3,
+    null,
+    ["brand", "category", "price"]
+  ]
+}
+```
+
+Redis-like:
+```bash
+LANCE.SEARCH products K 3 QUERY "boots for hiking in wet conditions" RETURN 3 brand category price
+```
+
+Expected response:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 8,
+  "result": {
+    "results": [
+      {
+        "id": "item-1",
+        "score": 0.234,
+        "meta": {
+          "brand": "TrailMax",
+          "category": "footwear",
+          "price": "129.99"
+        }
+      },
+      ...
+    ]
+  }
+}
+```
+
+**Step 6: Search with metadata filter**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 9,
+  "method": "herodb_lanceSearchText",
+  "params": [
+    1,
+    "products",
+    "comfortable shoes for running",
+    5,
+    "category = 'footwear'",
+    null
+  ]
+}
+```
+
+Redis-like:
+```bash
+LANCE.SEARCH products K 5 QUERY "comfortable shoes for running" FILTER "category = 'footwear'"
+```
+
+This returns only items where `category` equals `'footwear'`.
+
+**Step 7: List datasets**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 10,
+  "method": "herodb_lanceList",
+  "params": [1]
+}
+```
+
+Redis-like:
+```bash
+LANCE.LIST
+```
+
+**Step 8: Get dataset info**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 11,
+  "method": "herodb_lanceInfo",
+  "params": [1, "products"]
+}
+```
+
+Redis-like:
+```bash
+LANCE.INFO products
+```
+
+Returns dimension, row count, and other metadata.
+
+---
+
+## Scenario 2: OpenAI API
+
+Use OpenAI's production embedding service for semantic search.
+
+### Setup
+
+**1. Set your API key:**
+
+```bash
+export OPENAI_API_KEY="sk-your-actual-openai-key-here"
+```
+
+**2. Start HeroDB** (same as before):
+
+```bash
+./target/release/herodb --dir ./data --admin-secret my-admin-secret --enable-rpc --rpc-port 8080
+```
+
+### End-to-End Example with OpenAI
+
+**Step 1: Create a Lance database**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "herodb_createDatabase",
+  "params": [
+    "Lance",
+    { "name": "openai-vectors", "storage_path": null, "max_size": null, "redis_version": null },
+    null
+  ]
+}
+```
+
+Expected: `{"jsonrpc":"2.0","id":1,"result":1}` (database ID = 1)
+
+**Step 2: Configure OpenAI embeddings**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 2,
+  "method": "herodb_lanceSetEmbeddingConfig",
+  "params": [
+    1,
+    "documents",
+    {
+      "provider": "openai",
+      "model": "text-embedding-3-small",
+      "dim": 1536,
+      "endpoint": null,
+      "headers": {},
+      "timeout_ms": 30000
+    }
+  ]
+}
+```
+
+Redis-like:
+```bash
+redis-cli -p 6379
+SELECT 1
+LANCE.EMBEDDING CONFIG SET documents PROVIDER openai MODEL text-embedding-3-small DIM 1536 TIMEOUTMS 30000
+```
+
+Notes:
+- `endpoint` is `null` (defaults to OpenAI API: https://api.openai.com/v1/embeddings)
+- `headers` is empty (Authorization auto-added from OPENAI_API_KEY env var)
+- `dim` is 1536 for text-embedding-3-small
+
+Expected: `{"jsonrpc":"2.0","id":2,"result":true}`
+
+**Step 3: Insert documents**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 3,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "documents",
+    "doc-1",
+    "The quick brown fox jumps over the lazy dog",
+    { "source": "example", "lang": "en", "topic": "animals" }
+  ]
+}
+```
+
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 4,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "documents",
+    "doc-2",
+    "Machine learning models require large datasets for training and validation",
+    { "source": "tech", "lang": "en", "topic": "ai" }
+  ]
+}
+```
+
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 5,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "documents",
+    "doc-3",
+    "Python is a popular programming language for data science and web development",
+    { "source": "tech", "lang": "en", "topic": "programming" }
+  ]
+}
+```
+
+Redis-like:
+```bash
+LANCE.STORE documents ID doc-1 TEXT "The quick brown fox jumps over the lazy dog" META source example lang en topic animals
+LANCE.STORE documents ID doc-2 TEXT "Machine learning models require large datasets for training and validation" META source tech lang en topic ai
+LANCE.STORE documents ID doc-3 TEXT "Python is a popular programming language for data science and web development" META source tech lang en topic programming
+```
+
+Expected for each: `{"jsonrpc":"2.0","id":N,"result":true}`
+
+**Step 4: Semantic search**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 6,
+  "method": "herodb_lanceSearchText",
+  "params": [
+    1,
+    "documents",
+    "artificial intelligence and neural networks",
+    3,
+    null,
+    ["source", "topic"]
+  ]
+}
+```
+
+Redis-like:
+```bash
+LANCE.SEARCH documents K 3 QUERY "artificial intelligence and neural networks" RETURN 2 source topic
+```
+
+Expected response (doc-2 should rank highest due to semantic similarity):
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 6,
+  "result": {
+    "results": [
+      {
+        "id": "doc-2",
+        "score": 0.123,
+        "meta": {
+          "source": "tech",
+          "topic": "ai"
+        }
+      },
+      {
+        "id": "doc-3",
+        "score": 0.456,
+        "meta": {
+          "source": "tech",
+          "topic": "programming"
+        }
+      },
+      {
+        "id": "doc-1",
+        "score": 0.789,
+        "meta": {
+          "source": "example",
+          "topic": "animals"
+        }
+      }
+    ]
+  }
+}
+```
+
+Note: Lower score = better match (L2 distance).
+
+**Step 5: Search with filter**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 7,
+  "method": "herodb_lanceSearchText",
+  "params": [
+    1,
+    "documents",
+    "programming and software",
+    5,
+    "topic = 'programming'",
+    null
+  ]
+}
+```
+
+Redis-like:
+```bash
+LANCE.SEARCH documents K 5 QUERY "programming and software" FILTER "topic = 'programming'"
+```
+
+This returns only documents where `topic` equals `'programming'`.
+
+---
+
+## Scenario 2: OpenAI API
+
+Use OpenAI's production embedding service for high-quality semantic search.
+
+### Setup
+
+**1. Set your OpenAI API key:**
+
+```bash
+export OPENAI_API_KEY="sk-your-actual-openai-key-here"
+```
+
+**2. Start HeroDB:**
+
+```bash
+./target/release/herodb --dir ./data --admin-secret my-admin-secret --enable-rpc --rpc-port 8080
+```
+
+### Complete Workflow
+
+**Step 1: Create database**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "herodb_createDatabase",
+  "params": [
+    "Lance",
+    { "name": "openai-docs", "storage_path": null, "max_size": null, "redis_version": null },
+    null
+  ]
+}
+```
+
+**Step 2: Configure OpenAI embeddings**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 2,
+  "method": "herodb_lanceSetEmbeddingConfig",
+  "params": [
+    1,
+    "articles",
+    {
+      "provider": "openai",
+      "model": "text-embedding-3-small",
+      "dim": 1536,
+      "endpoint": null,
+      "headers": {},
+      "timeout_ms": 30000
+    }
+  ]
+}
+```
+
+Redis-like:
+```bash
+SELECT 1
+LANCE.EMBEDDING CONFIG SET articles PROVIDER openai MODEL text-embedding-3-small DIM 1536
+```
+
+**Step 3: Insert articles**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 3,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "articles",
+    "article-1",
+    "Climate change is affecting global weather patterns and ecosystems",
+    { "category": "environment", "author": "Jane Smith", "year": "2024" }
+  ]
+}
+```
+
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 4,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "articles",
+    "article-2",
+    "Quantum computing promises to revolutionize cryptography and drug discovery",
+    { "category": "technology", "author": "John Doe", "year": "2024" }
+  ]
+}
+```
+
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 5,
+  "method": "herodb_lanceStoreText",
+  "params": [
+    1,
+    "articles",
+    "article-3",
+    "Renewable energy sources like solar and wind are becoming more cost-effective",
+    { "category": "environment", "author": "Alice Johnson", "year": "2023" }
+  ]
+}
+```
+
+**Step 4: Semantic search**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 6,
+  "method": "herodb_lanceSearchText",
+  "params": [
+    1,
+    "articles",
+    "environmental sustainability and green energy",
+    2,
+    null,
+    ["category", "author"]
+  ]
+}
+```
+
+Redis-like:
+```bash
+LANCE.SEARCH articles K 2 QUERY "environmental sustainability and green energy" RETURN 2 category author
+```
+
+Expected: Returns article-1 and article-3 (both environment-related).
+
+**Step 5: Filtered search**
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 7,
+  "method": "herodb_lanceSearchText",
+  "params": [
+    1,
+    "articles",
+    "new technology innovations",
+    5,
+    "category = 'technology'",
+    null
+  ]
+}
+```
+
+---
+
+## Scenario 3: Deterministic Test Embedder (No Network)
+
+For CI/offline development, use the built-in test embedder that requires no external service.
+
+### Configuration
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "herodb_lanceSetEmbeddingConfig",
+  "params": [
+    1,
+    "testdata",
+    {
+      "provider": "test",
+      "model": "dev",
+      "dim": 64,
+      "endpoint": null,
+      "headers": {},
+      "timeout_ms": null
+    }
+  ]
+}
+```
+
+Redis-like:
+```bash
+SELECT 1
+LANCE.EMBEDDING CONFIG SET testdata PROVIDER test MODEL dev DIM 64
+```
+
+### Usage
+
+Use `lanceStoreText` and `lanceSearchText` as in previous scenarios. The embeddings are:
+- Deterministic (same text → same vector)
+- Fast (no network)
+- Not semantic (hash-based, not ML)
+
+Perfect for testing the vector storage/search mechanics without external dependencies.
+
+---
+
+## Advanced: Custom Headers and Timeouts
+
+### Example: Local model with custom auth
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "herodb_lanceSetEmbeddingConfig",
+  "params": [
+    1,
+    "secure-data",
+    {
+      "provider": "openai",
+      "model": "custom-model",
+      "dim": 512,
+      "endpoint": "http://192.168.1.100:9000/embeddings",
+      "headers": {
+        "Authorization": "Bearer my-local-token",
+        "X-Custom-Header": "value"
+      },
+      "timeout_ms": 60000
+    }
+  ]
+}
+```
+
+### Example: OpenAI with explicit API key (not from env)
+
+JSON-RPC:
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "herodb_lanceSetEmbeddingConfig",
+  "params": [
+    1,
+    "dataset",
+    {
+      "provider": "openai",
+      "model": "text-embedding-3-small",
+      "dim": 1536,
+      "endpoint": null,
+      "headers": {
+        "Authorization": "Bearer sk-your-key-here"
+      },
+      "timeout_ms": 30000
+    }
+  ]
+}
+```
+
+---
+
+## Troubleshooting
+
+### Error: "Embedding config not set for dataset"
+
+**Cause:** You tried to use `lanceStoreText` or `lanceSearchText` without configuring an embedder.
+
+**Solution:** Run `lanceSetEmbeddingConfig` first.
+
+### Error: "Embedding dimension mismatch: expected X, got Y"
+
+**Cause:** The embedding service returned vectors of a different size than configured.
+
+**Solution:** 
+- For OpenAI text-embedding-3-small, use `dim: 1536`
+- For your local mock (from this tutorial), use `dim: 768`
+- Check your embedding service's actual output dimension
+
+### Error: "Missing API key in env 'OPENAI_API_KEY'"
+
+**Cause:** Using OpenAI provider without setting the API key.
+
+**Solution:**
+- Set `export OPENAI_API_KEY="sk-..."` before starting HeroDB, OR
+- Pass the key explicitly in headers: `"Authorization": "Bearer sk-..."`
+
+### Error: "HTTP request failed" or "Embeddings API error 404"
+
+**Cause:** Cannot reach the embedding endpoint.
+
+**Solution:**
+- Verify your local server is running: `curl http://127.0.0.1:8081/v1/embeddings`
+- Check the endpoint URL in your config
+- Ensure firewall allows the connection
+
+### Error: "ERR DB backend is not Lance"
+
+**Cause:** Trying to use LANCE.* commands on a non-Lance database.
+
+**Solution:** Create the database with backend "Lance" (see Step 1).
+
+### Error: "write permission denied"
+
+**Cause:** Database is private and you haven't authenticated.
+
+**Solution:** Use `SELECT <db_id> KEY <access-key>` or make the database public via RPC.
+
+---
+
+## Complete Example Script (Bash + curl)
+
+Save as `test_embeddings.sh`:
+
+```bash
+#!/bin/bash
+
+RPC_URL="http://localhost:8080"
+
+# 1. Create Lance database
+curl -X POST $RPC_URL -H "Content-Type: application/json" -d '{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "herodb_createDatabase",
+  "params": ["Lance", {"name": "test-vectors", "storage_path": null, "max_size": null, "redis_version": null}, null]
+}'
+
+echo -e "\n"
+
+# 2. Configure local embedder
+curl -X POST $RPC_URL -H "Content-Type: application/json" -d '{
+  "jsonrpc": "2.0",
+  "id": 2,
+  "method": "herodb_lanceSetEmbeddingConfig",
+  "params": [1, "products", {
+    "provider": "openai",
+    "model": "mock",
+    "dim": 768,
+    "endpoint": "http://127.0.0.1:8081/v1/embeddings",
+    "headers": {"Authorization": "Bearer dummy"},
+    "timeout_ms": 30000
+  }]
+}'
+
+echo -e "\n"
+
+# 3. Insert data
+curl -X POST $RPC_URL -H "Content-Type: application/json" -d '{
+  "jsonrpc": "2.0",
+  "id": 3,
+  "method": "herodb_lanceStoreText",
+  "params": [1, "products", "item-1", "Hiking boots", {"brand": "TrailMax"}]
+}'
+
+echo -e "\n"
+
+# 4. Search
+curl -X POST $RPC_URL -H "Content-Type: application/json" -d '{
+  "jsonrpc": "2.0",
+  "id": 4,
+  "method": "herodb_lanceSearchText",
+  "params": [1, "products", "outdoor footwear", 5, null, null]
+}'
+
+echo -e "\n"
+```
+
+Run:
+```bash
+chmod +x test_embeddings.sh
+./test_embeddings.sh
+```
+
+---
+
+## Summary
+
+| Provider | Use Case | Endpoint | API Key |
+|----------|----------|----------|---------|
+| `openai` | Production semantic search | Default (OpenAI) or custom URL | OPENAI_API_KEY env or headers |
+| `openai` | Local self-hosted gateway | http://127.0.0.1:8081/... | Optional (depends on your service) |
+| `test` | CI/offline development | N/A (local hash) | None |
+| `image_test` | Image testing | N/A (local hash) | None |
+
+**Notes:**
+- The `provider` field is always `"openai"` for OpenAI-compatible services (whether cloud or local). This is because it uses the OpenAI-compatible API shape.
+- Use `endpoint` to point to your local service
+- Use `headers` for custom authentication
+- `dim` must match your embedding service's output dimension
+- Once configured, `lanceStoreText` and `lanceSearchText` handle embedding automatically

mock_embedder.py

@@ -0,0 +1,34 @@
+from flask import Flask, request, jsonify
+import numpy as np
+
+app = Flask(__name__)
+
+@app.route('/v1/embeddings', methods=['POST'])
+def embeddings():
+    data = request.json
+    inputs = data.get('input', [])
+    if isinstance(inputs, str):
+        inputs = [inputs]
+    
+    # Generate deterministic 768-dim embeddings (hash-based)
+    embeddings = []
+    for text in inputs:
+        # Simple hash to vector
+        vec = np.zeros(768)
+        for i, char in enumerate(text[:768]):
+            vec[i % 768] += ord(char) / 255.0
+        # Normalize
+        norm = np.linalg.norm(vec)
+        if norm > 0:
+            vec = vec / norm
+        embeddings.append(vec.tolist())
+    
+    return jsonify({
+        "data": [{"embedding": emb} for emb in embeddings],
+        "model": data.get('model', 'mock'),
+        "usage": {"total_tokens": sum(len(t) for t in inputs)}
+    })
+
+if __name__ == '__main__':
+    app.run(host='127.0.0.1', port=8081)
+

src/cmd.rs

@@ -1,4 +1,4 @@
-use crate::{error::DBError, protocol::Protocol, server::Server, embedding::{EmbeddingConfig, EmbeddingProvider}};
+use crate::{error::DBError, protocol::Protocol, server::Server, embedding::EmbeddingConfig};
 use base64::{engine::general_purpose, Engine as _};
 use tokio::time::{timeout, Duration};
 use futures::future::select_all;
@@ -170,9 +170,7 @@ pub enum Cmd {
     // Embedding configuration per dataset
     LanceEmbeddingConfigSet {
         name: String,
-        provider: String,
+        config: EmbeddingConfig,
-        model: String,
-        params: Vec<(String, String)>,
     },
     LanceEmbeddingConfigGet {
         name: String,
@@ -1089,20 +1087,25 @@ impl Cmd {
                             Cmd::LanceCreateIndex { name, index_type, params }
                         }
                         "lance.embedding" => {
-                            // LANCE.EMBEDDING CONFIG SET name PROVIDER p MODEL m [PARAM k v ...]
+                            // LANCE.EMBEDDING CONFIG SET name PROVIDER p MODEL m DIM d [ENDPOINT url] [HEADER k v]... [TIMEOUTMS t]
                             // LANCE.EMBEDDING CONFIG GET name
                             if cmd.len() < 3 || cmd[1].to_uppercase() != "CONFIG" {
                                 return Err(DBError("ERR LANCE.EMBEDDING requires CONFIG subcommand".to_string()));
                             }
                             if cmd.len() >= 4 && cmd[2].to_uppercase() == "SET" {
                                 if cmd.len() < 8 {
-                                    return Err(DBError("ERR LANCE.EMBEDDING CONFIG SET requires: SET name PROVIDER p MODEL m [PARAM k v ...]".to_string()));
+                                    return Err(DBError("ERR LANCE.EMBEDDING CONFIG SET requires: SET name PROVIDER p MODEL m DIM d [ENDPOINT url] [HEADER k v]... [TIMEOUTMS t]".to_string()));
                                 }
                                 let name = cmd[3].clone();
                                 let mut i = 4;
+
                                 let mut provider: Option<String> = None;
                                 let mut model: Option<String> = None;
-                                let mut params: Vec<(String, String)> = Vec::new();
+                                let mut dim: Option<usize> = None;
+                                let mut endpoint: Option<String> = None;
+                                let mut headers: std::collections::HashMap<String, String> = std::collections::HashMap::new();
+                                let mut timeout_ms: Option<u64> = None;
+
                                 while i < cmd.len() {
                                     match cmd[i].to_uppercase().as_str() {
                                         "PROVIDER" => {
@@ -1119,22 +1122,62 @@ impl Cmd {
                                             model = Some(cmd[i + 1].clone());
                                             i += 2;
                                         }
-                                        "PARAM" => {
+                                        "DIM" => {
-                                            i += 1;
+                                            if i + 1 >= cmd.len() {
-                                            while i + 1 < cmd.len() {
+                                                return Err(DBError("ERR DIM requires a value".to_string()));
-                                                params.push((cmd[i].clone(), cmd[i + 1].clone()));
-                                                i += 2;
                                             }
+                                            let d: usize = cmd[i + 1].parse().map_err(|_| DBError("ERR DIM must be an integer".to_string()))?;
+                                            dim = Some(d);
+                                            i += 2;
+                                        }
+                                        "ENDPOINT" => {
+                                            if i + 1 >= cmd.len() {
+                                                return Err(DBError("ERR ENDPOINT requires a value".to_string()));
+                                            }
+                                            endpoint = Some(cmd[i + 1].clone());
+                                            i += 2;
+                                        }
+                                        "HEADER" => {
+                                            if i + 2 >= cmd.len() {
+                                                return Err(DBError("ERR HEADER requires key and value".to_string()));
+                                            }
+                                            headers.insert(cmd[i + 1].clone(), cmd[i + 2].clone());
+                                            i += 3;
+                                        }
+                                        "TIMEOUTMS" => {
+                                            if i + 1 >= cmd.len() {
+                                                return Err(DBError("ERR TIMEOUTMS requires a value".to_string()));
+                                            }
+                                            let t: u64 = cmd[i + 1].parse().map_err(|_| DBError("ERR TIMEOUTMS must be an integer".to_string()))?;
+                                            timeout_ms = Some(t);
+                                            i += 2;
                                         }
                                         _ => {
-                                            // Unknown token; break to avoid infinite loop
                                             i += 1;
                                         }
                                     }
                                 }
-                                let provider = provider.ok_or_else(|| DBError("ERR missing PROVIDER".to_string()))?;
+
+                                let provider_str = provider.ok_or_else(|| DBError("ERR missing PROVIDER".to_string()))?;
+                                let provider_enum = match provider_str.to_lowercase().as_str() {
+                                    "openai" => crate::embedding::EmbeddingProvider::openai,
+                                    "test" => crate::embedding::EmbeddingProvider::test,
+                                    "image_test" | "imagetest" | "image-test" => crate::embedding::EmbeddingProvider::image_test,
+                                    other => return Err(DBError(format!("ERR unsupported provider '{}'", other))),
+                                };
                                 let model = model.ok_or_else(|| DBError("ERR missing MODEL".to_string()))?;
-                                Cmd::LanceEmbeddingConfigSet { name, provider, model, params }
+                                let dim = dim.ok_or_else(|| DBError("ERR missing DIM".to_string()))?;
+
+                                let config = EmbeddingConfig {
+                                    provider: provider_enum,
+                                    model,
+                                    dim,
+                                    endpoint,
+                                    headers,
+                                    timeout_ms,
+                                };
+
+                                Cmd::LanceEmbeddingConfigSet { name, config }
                             } else if cmd.len() == 4 && cmd[2].to_uppercase() == "GET" {
                                 let name = cmd[3].clone();
                                 Cmd::LanceEmbeddingConfigGet { name }
@@ -1437,25 +1480,14 @@ impl Cmd {
                     Err(e) => Ok(Protocol::err(&e.0)),
                 }
             }
-            Cmd::LanceEmbeddingConfigSet { name, provider, model, params } => {
+            Cmd::LanceEmbeddingConfigSet { name, config } => {
                 if !server.has_write_permission() {
                     return Ok(Protocol::err("ERR write permission denied"));
                 }
-                // Map provider string to enum
+                if config.dim == 0 {
-                let p_lc = provider.to_lowercase();
+                    return Ok(Protocol::err("ERR embedding DIM must be > 0"));
-                let prov = match p_lc.as_str() {
+                }
-                    "test-hash" | "testhash" => EmbeddingProvider::TestHash,
+                match server.set_dataset_embedding_config(&name, &config) {
-                    "testimagehash" | "image-test-hash" | "imagetesthash" => EmbeddingProvider::ImageTestHash,
-                    "fastembed" | "lancefastembed" => EmbeddingProvider::LanceFastEmbed,
-                    "openai" | "lanceopenai" => EmbeddingProvider::LanceOpenAI,
-                    other => EmbeddingProvider::LanceOther(other.to_string()),
-                };
-                let cfg = EmbeddingConfig {
-                    provider: prov,
-                    model,
-                    params: params.into_iter().collect(),
-                };
-                match server.set_dataset_embedding_config(&name, &cfg) {
                     Ok(()) => Ok(Protocol::SimpleString("OK".to_string())),
                     Err(e) => Ok(Protocol::err(&e.0)),
                 }
@@ -1466,16 +1498,20 @@ impl Cmd {
                         let mut arr = Vec::new();
                         arr.push(Protocol::BulkString("provider".to_string()));
                         arr.push(Protocol::BulkString(match cfg.provider {
-                            EmbeddingProvider::TestHash => "test-hash".to_string(),
+                            crate::embedding::EmbeddingProvider::openai => "openai".to_string(),
-                            EmbeddingProvider::ImageTestHash => "testimagehash".to_string(),
+                            crate::embedding::EmbeddingProvider::test => "test".to_string(),
-                            EmbeddingProvider::LanceFastEmbed => "lancefastembed".to_string(),
+                            crate::embedding::EmbeddingProvider::image_test => "image_test".to_string(),
-                            EmbeddingProvider::LanceOpenAI => "lanceopenai".to_string(),
-                            EmbeddingProvider::LanceOther(ref s) => s.clone(),
                         }));
                         arr.push(Protocol::BulkString("model".to_string()));
                         arr.push(Protocol::BulkString(cfg.model.clone()));
-                        arr.push(Protocol::BulkString("params".to_string()));
+                        arr.push(Protocol::BulkString("dim".to_string()));
-                        arr.push(Protocol::BulkString(serde_json::to_string(&cfg.params).unwrap_or_else(|_| "{}".to_string())));
+                        arr.push(Protocol::BulkString(cfg.dim.to_string()));
+                        arr.push(Protocol::BulkString("endpoint".to_string()));
+                        arr.push(Protocol::BulkString(cfg.endpoint.clone().unwrap_or_default()));
+                        arr.push(Protocol::BulkString("timeout_ms".to_string()));
+                        arr.push(Protocol::BulkString(cfg.timeout_ms.map(|v| v.to_string()).unwrap_or_default()));
+                        arr.push(Protocol::BulkString("headers".to_string()));
+                        arr.push(Protocol::BulkString(serde_json::to_string(&cfg.headers).unwrap_or_else(|_| "{}".to_string())));
                         Ok(Protocol::Array(arr))
                     }
                     Err(e) => Ok(Protocol::err(&e.0)),

src/embedding.rs

@@ -1,4 +1,4 @@
-// Embedding abstraction and minimal providers.
+// Embedding abstraction with a single external provider (OpenAI-compatible) and local test providers.
 
 use std::collections::HashMap;
 use std::sync::Arc;
@@ -7,42 +7,41 @@ use serde::{Deserialize, Serialize};
 
 use crate::error::DBError;
 
-// Networking for OpenAI/Azure
+// Networking for OpenAI-compatible endpoints
 use std::time::Duration;
 use ureq::{Agent, AgentBuilder};
 use serde_json::json;
 
-/// Provider identifiers. Extend as needed to mirror LanceDB-supported providers.
+/// Provider identifiers (minimal set).
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
 #[serde(rename_all = "snake_case")]
 pub enum EmbeddingProvider {
-    // Deterministic, local-only embedder for CI and offline development (text).
+    /// External HTTP provider compatible with OpenAI's embeddings API.
-    TestHash,
+    openai,
-    // Deterministic, local-only embedder for CI and offline development (image).
+    /// Deterministic, local-only embedder for CI and offline development (text).
-    ImageTestHash,
+    test,
-    // Placeholders for LanceDB-supported providers; implementers can add concrete backends later.
+    /// Deterministic, local-only embedder for CI and offline development (image).
-    LanceFastEmbed,
+    image_test,
-    LanceOpenAI,
-    LanceOther(String),
 }
 
 /// Serializable embedding configuration.
-/// params: arbitrary key-value map for provider-specific knobs (e.g., "dim", "api_key_env", etc.)
+/// - provider: "openai" | "test" | "image_test"
+/// - model: provider/model id (e.g., "text-embedding-3-small"), may be ignored by local gateways
+/// - dim: required output dimension (used to create Lance datasets and validate outputs)
+/// - endpoint: optional HTTP endpoint (defaults to OpenAI API when provider == openai)
+/// - headers: optional HTTP headers (e.g., Authorization). If empty and OPENAI_API_KEY is present, Authorization will be inferred.
+/// - timeout_ms: optional HTTP timeout in milliseconds (for both read and write)
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct EmbeddingConfig {
     pub provider: EmbeddingProvider,
     pub model: String,
+    pub dim: usize,
     #[serde(default)]
-    pub params: HashMap<String, String>,
+    pub endpoint: Option<String>,
-}
+    #[serde(default)]
-
+    pub headers: HashMap<String, String>,
-impl EmbeddingConfig {
+    #[serde(default)]
-    pub fn get_param_usize(&self, key: &str) -> Option<usize> {
+    pub timeout_ms: Option<u64>,
-        self.params.get(key).and_then(|v| v.parse::<usize>().ok())
-    }
-    pub fn get_param_string(&self, key: &str) -> Option<String> {
-        self.params.get(key).cloned()
-    }
 }
 
 /// A provider-agnostic text embedding interface.
@@ -59,6 +58,20 @@ pub trait Embedder: Send + Sync {
     }
 }
 
+/// Image embedding interface (separate from text to keep modality-specific inputs).
+pub trait ImageEmbedder: Send + Sync {
+    /// Human-readable provider/model name
+    fn name(&self) -> String;
+    /// Embedding dimension
+    fn dim(&self) -> usize;
+    /// Embed a single image (raw bytes)
+    fn embed_image(&self, bytes: &[u8]) -> Result<Vec<f32>, DBError>;
+    /// Embed many images; default maps embed_image() over inputs
+    fn embed_many_images(&self, images: &[Vec<u8>]) -> Result<Vec<Vec<f32>>, DBError> {
+        images.iter().map(|b| self.embed_image(b)).collect()
+    }
+}
+
 //// ----------------------------- TEXT: deterministic test embedder -----------------------------
 
 /// Deterministic, no-deps, no-network embedder for CI and offline dev.
@@ -88,7 +101,7 @@ impl TestHashEmbedder {
 
 impl Embedder for TestHashEmbedder {
     fn name(&self) -> String {
-        format!("test-hash:{}", self.model_name)
+        format!("test:{}", self.model_name)
     }
 
     fn dim(&self) -> usize {
@@ -117,21 +130,7 @@ impl Embedder for TestHashEmbedder {
     }
 }
 
-//// ----------------------------- IMAGE: trait + deterministic test embedder -----------------------------
+//// ----------------------------- IMAGE: deterministic test embedder -----------------------------
-
-/// Image embedding interface (separate from text to keep modality-specific inputs).
-pub trait ImageEmbedder: Send + Sync {
-    /// Human-readable provider/model name
-    fn name(&self) -> String;
-    /// Embedding dimension
-    fn dim(&self) -> usize;
-    /// Embed a single image (raw bytes)
-    fn embed_image(&self, bytes: &[u8]) -> Result<Vec<f32>, DBError>;
-    /// Embed many images; default maps embed_image() over inputs
-    fn embed_many_images(&self, images: &[Vec<u8>]) -> Result<Vec<Vec<f32>>, DBError> {
-        images.iter().map(|b| self.embed_image(b)).collect()
-    }
-}
 
 /// Deterministic image embedder that folds bytes into buckets, applies tanh-like nonlinearity,
 /// and L2-normalizes. Suitable for CI and offline development.
@@ -159,7 +158,7 @@ impl TestImageHashEmbedder {
 
 impl ImageEmbedder for TestImageHashEmbedder {
     fn name(&self) -> String {
-        format!("test-image-hash:{}", self.model_name)
+        format!("image_test:{}", self.model_name)
     }
 
     fn dim(&self) -> usize {
@@ -188,80 +187,45 @@ impl ImageEmbedder for TestImageHashEmbedder {
     }
 }
 
-//// OpenAI embedder (supports OpenAI and Azure OpenAI via REST)
+//// ----------------------------- OpenAI-compatible HTTP embedder -----------------------------
+
 struct OpenAIEmbedder {
     model: String,
     dim: usize,
     agent: Agent,
     endpoint: String,
     headers: Vec<(String, String)>,
-    use_azure: bool,
 }
 
 impl OpenAIEmbedder {
     fn new_from_config(cfg: &EmbeddingConfig) -> Result<Self, DBError> {
-        // Whether to use Azure OpenAI
-        let use_azure = cfg
-            .get_param_string("use_azure")
-            .map(|s| s.eq_ignore_ascii_case("true"))
-            .unwrap_or(false);
-
-        // Resolve API key (OPENAI_API_KEY or AZURE_OPENAI_API_KEY by default)
-        let api_key_env = cfg
-            .get_param_string("api_key_env")
-            .unwrap_or_else(|| {
-                if use_azure {
-                    "AZURE_OPENAI_API_KEY".to_string()
-                } else {
-                    "OPENAI_API_KEY".to_string()
-                }
-            });
-        let api_key = std::env::var(&api_key_env)
-            .map_err(|_| DBError(format!("Missing API key in env '{}'", api_key_env)))?;
-
         // Resolve endpoint
-        // - Standard OpenAI: https://api.openai.com/v1/embeddings (default) or params["base_url"]
+        let endpoint = cfg.endpoint.clone().unwrap_or_else(|| {
-        // - Azure OpenAI: {azure_endpoint}/openai/deployments/{deployment}/embeddings?api-version=...
+            "https://api.openai.com/v1/embeddings".to_string()
-        let endpoint = if use_azure {
+        });
-            let base = cfg
-                .get_param_string("azure_endpoint")
-                .ok_or_else(|| DBError("Missing 'azure_endpoint' for Azure OpenAI".into()))?;
-            let deployment = cfg
-                .get_param_string("azure_deployment")
-                .unwrap_or_else(|| cfg.model.clone());
-            let api_version = cfg
-                .get_param_string("azure_api_version")
-                .unwrap_or_else(|| "2023-05-15".to_string());
-            format!(
-                "{}/openai/deployments/{}/embeddings?api-version={}",
-                base.trim_end_matches('/'),
-                deployment,
-                api_version
-            )
-        } else {
-            cfg.get_param_string("base_url")
-                .unwrap_or_else(|| "https://api.openai.com/v1/embeddings".to_string())
-        };
 
-        // Determine expected dimension (default 1536 for text-embedding-3-small; callers should override if needed)
+        // Determine expected dimension (required by config)
-        let dim = cfg
+        let dim = cfg.dim;
-            .get_param_usize("dim")
-            .or_else(|| cfg.get_param_usize("dimensions"))
-            .unwrap_or(1536);
 
         // Build an HTTP agent with timeouts (blocking; no tokio runtime involved)
+        let to_ms = cfg.timeout_ms.unwrap_or(30_000);
         let agent = AgentBuilder::new()
-            .timeout_read(Duration::from_secs(30))
+            .timeout_read(Duration::from_millis(to_ms))
-            .timeout_write(Duration::from_secs(30))
+            .timeout_write(Duration::from_millis(to_ms))
             .build();
 
-        // Headers
+        // Headers: start from cfg.headers, and add Authorization from env if absent and available
-        let mut headers: Vec<(String, String)> = Vec::new();
+        let mut headers: Vec<(String, String)> =
-        headers.push(("Content-Type".to_string(), "application/json".to_string()));
+            cfg.headers.iter().map(|(k, v)| (k.clone(), v.clone())).collect();
-        if use_azure {
+
-            headers.push(("api-key".to_string(), api_key));
+        if !headers.iter().any(|(k, _)| k.eq_ignore_ascii_case("content-type")) {
-        } else {
+            headers.push(("Content-Type".to_string(), "application/json".to_string()));
-            headers.push(("Authorization".to_string(), format!("Bearer {}", api_key)));
+        }
+
+        if !headers.iter().any(|(k, _)| k.eq_ignore_ascii_case("authorization")) {
+            if let Ok(key) = std::env::var("OPENAI_API_KEY") {
+                headers.push(("Authorization".to_string(), format!("Bearer {}", key)));
+            }
         }
 
         Ok(Self {
@@ -270,19 +234,12 @@ impl OpenAIEmbedder {
             agent,
             endpoint,
             headers,
-            use_azure,
         })
     }
 
     fn request_many(&self, inputs: &[String]) -> Result<Vec<Vec<f32>>, DBError> {
-        // Compose request body:
+        // Compose request body (OpenAI-compatible)
-        // - Standard OpenAI: { "model": ..., "input": [...], "dimensions": dim? }
+        let mut body = json!({ "model": self.model, "input": inputs });
-        // - Azure:           { "input": [...], "dimensions": dim? } (model from deployment)
-        let mut body = if self.use_azure {
-            json!({ "input": inputs })
-        } else {
-            json!({ "model": self.model, "input": inputs })
-        };
         if self.dim > 0 {
             body.as_object_mut()
                 .unwrap()
@@ -331,7 +288,7 @@ impl OpenAIEmbedder {
             }
             if self.dim > 0 && v.len() != self.dim {
                 return Err(DBError(format!(
-                    "Embedding dimension mismatch: expected {}, got {}. Configure 'dim' or 'dimensions' to match output.",
+                    "Embedding dimension mismatch: expected {}, got {}. Configure 'dim' to match output.",
                     self.dim, v.len()
                 )));
             }
@@ -343,11 +300,7 @@ impl OpenAIEmbedder {
 
 impl Embedder for OpenAIEmbedder {
     fn name(&self) -> String {
-        if self.use_azure {
+        format!("openai:{}", self.model)
-            format!("azure-openai:{}", self.model)
-        } else {
-            format!("openai:{}", self.model)
-        }
     }
 
     fn dim(&self) -> usize {
@@ -368,38 +321,33 @@ impl Embedder for OpenAIEmbedder {
 }
 
 /// Create an embedder instance from a config.
-/// - TestHash: uses params["dim"] or defaults to 64
+/// - openai: uses OpenAI-compatible embeddings REST API (endpoint override supported)
-/// - LanceOpenAI: uses OpenAI (or Azure OpenAI) embeddings REST API
+/// - test: deterministic local text embedder (no network)
-/// - Other Lance providers can be added similarly
+/// - image_test: not valid for text (use create_image_embedder)
 pub fn create_embedder(config: &EmbeddingConfig) -> Result<Arc<dyn Embedder>, DBError> {
     match &config.provider {
-        EmbeddingProvider::TestHash => {
+        EmbeddingProvider::openai => {
-            let dim = config.get_param_usize("dim").unwrap_or(64);
-            Ok(Arc::new(TestHashEmbedder::new(dim, config.model.clone())))
-        }
-        EmbeddingProvider::LanceOpenAI => {
             let inner = OpenAIEmbedder::new_from_config(config)?;
             Ok(Arc::new(inner))
         }
-        EmbeddingProvider::ImageTestHash => {
+        EmbeddingProvider::test => {
+            Ok(Arc::new(TestHashEmbedder::new(config.dim, config.model.clone())))
+        }
+        EmbeddingProvider::image_test => {
             Err(DBError("Use create_image_embedder() for image providers".into()))
         }
-        EmbeddingProvider::LanceFastEmbed => Err(DBError("LanceFastEmbed provider not yet implemented in Rust embedding layer; configure 'test-hash' or use 'openai'".into())),
-        EmbeddingProvider::LanceOther(p) => Err(DBError(format!("Lance provider '{}' not implemented; configure 'openai' or 'test-hash'", p))),
     }
 }
 
 /// Create an image embedder instance from a config.
+/// - image_test: deterministic local image embedder
 pub fn create_image_embedder(config: &EmbeddingConfig) -> Result<Arc<dyn ImageEmbedder>, DBError> {
     match &config.provider {
-        EmbeddingProvider::ImageTestHash => {
+        EmbeddingProvider::image_test => {
-            let dim = config.get_param_usize("dim").unwrap_or(512);
+            Ok(Arc::new(TestImageHashEmbedder::new(config.dim, config.model.clone())))
-            Ok(Arc::new(TestImageHashEmbedder::new(dim, config.model.clone())))
         }
-        EmbeddingProvider::TestHash | EmbeddingProvider::LanceOpenAI => {
+        EmbeddingProvider::test | EmbeddingProvider::openai => {
-            Err(DBError("Configured text provider; dataset expects image provider (e.g., 'testimagehash')".into()))
+            Err(DBError("Configured text provider; dataset expects image provider (e.g., 'image_test')".into()))
         }
-        EmbeddingProvider::LanceFastEmbed => Err(DBError("Image provider 'lancefastembed' not yet implemented".into())),
-        EmbeddingProvider::LanceOther(p) => Err(DBError(format!("Image provider '{}' not implemented; use 'testimagehash' for now", p))),
     }
 }

src/rpc.rs

@@ -9,7 +9,7 @@ use sha2::{Digest, Sha256};
 use crate::server::Server;
 use crate::options::DBOption;
 use crate::admin_meta;
-use crate::embedding::{EmbeddingConfig, EmbeddingProvider};
+use crate::embedding::EmbeddingConfig;
 use base64::{engine::general_purpose, Engine as _};
 
 /// Database backend types
@@ -248,9 +248,7 @@ pub trait Rpc {
         &self,
         db_id: u64,
         name: String,
-        provider: String,
+        config: EmbeddingConfig,
-        model: String,
-        params: Option<HashMap<String, String>>,
     ) -> RpcResult<bool>;
 
     /// Get per-dataset embedding configuration
@@ -1008,9 +1006,7 @@ impl RpcServer for RpcServerImpl {
         &self,
         db_id: u64,
         name: String,
-        provider: String,
+        config: EmbeddingConfig,
-        model: String,
-        params: Option<HashMap<String, String>>,
     ) -> RpcResult<bool> {
         let server = self.get_or_create_server(db_id).await?;
         if db_id == 0 {
@@ -1022,19 +1018,17 @@ impl RpcServer for RpcServerImpl {
         if !server.has_write_permission() {
             return Err(jsonrpsee::types::ErrorObjectOwned::owned(-32000, "write permission denied", None::<()>));
         }
-        let prov = match provider.to_lowercase().as_str() {
+        // Validate provider and dimension (only a minimal set is allowed for now)
-            "test-hash" | "testhash" => EmbeddingProvider::TestHash,
+        match config.provider {
-            "testimagehash" | "image-test-hash" | "imagetesthash" => EmbeddingProvider::ImageTestHash,
+            crate::embedding::EmbeddingProvider::openai
-            "fastembed" | "lancefastembed" => EmbeddingProvider::LanceFastEmbed,
+            | crate::embedding::EmbeddingProvider::test
-            "openai" | "lanceopenai" => EmbeddingProvider::LanceOpenAI,
+            | crate::embedding::EmbeddingProvider::image_test => {}
-            other => EmbeddingProvider::LanceOther(other.to_string()),
+        }
-        };
+        if config.dim == 0 {
-        let cfg = EmbeddingConfig {
+            return Err(jsonrpsee::types::ErrorObjectOwned::owned(-32000, "Invalid embedding config: dim must be > 0", None::<()>));
-            provider: prov,
+        }
-            model,
+
-            params: params.unwrap_or_default(),
+        server.set_dataset_embedding_config(&name, &config)
-        };
-        server.set_dataset_embedding_config(&name, &cfg)
             .map_err(|e| jsonrpsee::types::ErrorObjectOwned::owned(-32000, e.0, None::<()>))?;
         Ok(true)
     }
@@ -1056,17 +1050,7 @@ impl RpcServer for RpcServerImpl {
         }
         let cfg = server.get_dataset_embedding_config(&name)
             .map_err(|e| jsonrpsee::types::ErrorObjectOwned::owned(-32000, e.0, None::<()>))?;
-        Ok(serde_json::json!({
+        Ok(serde_json::to_value(&cfg).unwrap_or(serde_json::json!({})))
-            "provider": match cfg.provider {
-                EmbeddingProvider::TestHash => "test-hash",
-                EmbeddingProvider::ImageTestHash => "testimagehash",
-                EmbeddingProvider::LanceFastEmbed => "lancefastembed",
-                EmbeddingProvider::LanceOpenAI => "lanceopenai",
-                EmbeddingProvider::LanceOther(ref s) => s,
-            },
-            "model": cfg.model,
-            "params": cfg.params
-        }))
     }
 
     async fn lance_store_text(