feat: migrate backend from rust to go

This commit replaces the Axum/Rust backend with a Gin/Go implementation. The original Rust code has been archived in the 'rust' branch.

README.md

@@ -1,114 +1,108 @@
 # LLM Proxy Gateway
 
-A unified, high-performance LLM proxy gateway built in Rust. It provides a single OpenAI-compatible API to access multiple providers (OpenAI, Gemini, DeepSeek, Grok, Ollama) with built-in token tracking, real-time cost calculation, multi-user authentication, and a management dashboard.
+A unified, high-performance LLM proxy gateway built in Go. It provides a single OpenAI-compatible API to access multiple providers (OpenAI, Gemini, DeepSeek, Grok, Ollama) with built-in token tracking, real-time cost calculation, multi-user authentication, and a management dashboard.
 
 ## Features
 
 - **Unified API:** OpenAI-compatible `/v1/chat/completions` and `/v1/models` endpoints.
 - **Multi-Provider Support:**
   - **OpenAI:** GPT-4o, GPT-4o Mini, o1, o3 reasoning models.
-  - **Google Gemini:** Gemini 2.0 Flash, Pro, and vision models.
-  - **DeepSeek:** DeepSeek Chat and Reasoner models.
+  - **Google Gemini:** Gemini 2.0 Flash, Pro, and vision models (with native CoT support).
+  - **DeepSeek:** DeepSeek Chat and Reasoner (R1) models.
   - **xAI Grok:** Grok-beta models.
   - **Ollama:** Local LLMs running on your network.
 - **Observability & Tracking:**
-  - **Real-time Costing:** Fetches live pricing and context specs from `models.dev` on startup.
-  - **Token Counting:** Precise estimation using `tiktoken-rs`.
-  - **Database Logging:** Every request logged to SQLite for historical analysis.
-  - **Streaming Support:** Full SSE (Server-Sent Events) with `[DONE]` termination for client compatibility.
+  - **Asynchronous Logging:** Non-blocking request logging to SQLite using background workers.
+  - **Token Counting:** Precise estimation and tracking of prompt, completion, and reasoning tokens.
+  - **Database Persistence:** Every request logged to SQLite for historical analysis and dashboard analytics.
+  - **Streaming Support:** Full SSE (Server-Sent Events) support for all providers.
 - **Multimodal (Vision):** Image processing (Base64 and remote URLs) across compatible providers.
 - **Multi-User Access Control:**
   - **Admin Role:** Full access to all dashboard features, user management, and system configuration.
   - **Viewer Role:** Read-only access to usage analytics, costs, and monitoring.
   - **Client API Keys:** Create and manage multiple client tokens for external integrations.
 - **Reliability:**
-  - **Circuit Breaking:** Automatically protects when providers are down.
-  - **Rate Limiting:** Per-client and global rate limits.
-  - **Cache-Aware Costing:** Tracks cache hit/miss tokens for accurate billing.
+  - **Circuit Breaking:** Automatically protects when providers are down (coming soon).
+  - **Rate Limiting:** Per-client and global rate limits (coming soon).
 
 ## Security
 
 LLM Proxy is designed with security in mind:
 
-- **HMAC Session Tokens:** Management dashboard sessions are secured using HMAC-SHA256 signed tokens.
-- **Encrypted Provider Keys:** Sensitive LLM provider API keys are stored encrypted (AES-256-GCM) in the database.
-- **Session Refresh:** Activity-based session extension prevents session hijacking while maintaining user convenience.
-- **XSS Prevention:** Standardized frontend escaping using `window.api.escapeHtml`.
+- **Signed Session Tokens:** Management dashboard sessions are secured using HMAC-SHA256 signed tokens.
+- **Encrypted Storage:** Support for encrypted provider API keys in the database.
+- **Auth Middleware:** Secure client authentication via database-backed API keys.
 
-**Note:** You must define a `SESSION_SECRET` in your `.env` file for secure session signing.
+**Note:** You must define an `LLM_PROXY__ENCRYPTION_KEY` in your `.env` file for secure session signing and encryption.
 
 ## Tech Stack
 
-- **Runtime:** Rust with Tokio.
-- **Web Framework:** Axum.
-- **Database:** SQLx with SQLite.
-- **Frontend:** Vanilla JS/CSS with Chart.js for visualizations.
+- **Runtime:** Go 1.22+
+- **Web Framework:** Gin Gonic
+- **Database:** sqlx with SQLite (CGO-free via `modernc.org/sqlite`)
+- **Frontend:** Vanilla JS/CSS with Chart.js for visualizations
 
 ## Getting Started
 
 ### Prerequisites
 
-- Rust (1.80+)
-- SQLite3
+- Go (1.22+)
+- SQLite3 (optional, driver is built-in)
 - Docker (optional, for containerized deployment)
 
 ### Quick Start
 
 1. Clone and build:
    ```bash
-   git clone ssh://git.dustin.coffee:2222/hobokenchicken/llm-proxy.git
+   git clone <repository-url>
    cd llm-proxy
-   cargo build --release
+   go build -o llm-proxy ./cmd/llm-proxy
    ```
 
 2. Configure environment:
    ```bash
    cp .env.example .env
-   # Edit .env and add your API keys:
-   # SESSION_SECRET=... (Generate a strong random secret)
+   # Edit .env and add your configuration:
+   # LLM_PROXY__ENCRYPTION_KEY=... (32-byte hex or base64 string)
    # OPENAI_API_KEY=sk-...
    # GEMINI_API_KEY=AIza...
    ```
 
 3. Run the proxy:
    ```bash
-   cargo run --release
+   ./llm-proxy
    ```
 
-The server starts on `http://localhost:8080` by default.
+The server starts on `http://0.0.0.0:8080` by default.
 
 ### Deployment (Docker)
 
-A multi-stage `Dockerfile` is provided for efficient deployment:
-
 ```bash
 # Build the container
 docker build -t llm-proxy .
 
 # Run the container
 docker run -p 8080:8080 \
-  -e SESSION_SECRET=your-secure-secret \
+  -e LLM_PROXY__ENCRYPTION_KEY=your-secure-key \
   -v ./data:/app/data \
   llm-proxy
 ```
 
 ## Management Dashboard
 
-Access the dashboard at `http://localhost:8080`. The dashboard architecture has been refactored into modular sub-components for better maintainability:
+Access the dashboard at `http://localhost:8080`.
 
-- **Auth (`/api/auth`):** Login, session management, and password changes.
-- **Usage (`/api/usage`):** Summary stats, time-series analytics, and provider breakdown.
-- **Clients (`/api/clients`):** API key management and per-client usage tracking.
-- **Providers (`/api/providers`):** Provider configuration, status monitoring, and connection testing.
-- **System (`/api/system`):** Health metrics, live logs, database backups, and global settings.
+- **Auth:** Login, session management, and status tracking.
+- **Usage:** Summary stats, time-series analytics, and provider breakdown.
+- **Clients:** API key management and per-client usage tracking.
+- **Providers:** Provider configuration and status monitoring.
+- **Users:** Admin-only user management for dashboard access.
 - **Monitoring:** Live request stream via WebSocket.
 
 ### Default Credentials
 
 - **Username:** `admin`
-- **Password:** `admin123`
-
-Change the admin password in the dashboard after first login!
+- **Password:** `admin` (You will be prompted to change this or should change it manually in the dashboard)
 
 ## API Usage
 
@@ -131,4 +125,4 @@ response = client.chat.completions.create(
 
 ## License
 
-MIT OR Apache-2.0
+MIT