# OpenAI Flow

**Özet:** OpenAI-compatible isteklerin gateway üzerinden direkt passthrough akışı.

**Kütüphaneler:** Fiber v3, Go `net/http`

**Bağlantılar:** [[OpenAIHandler]], [[ProxyEngine]], [[RequestLog]], [[Index]]

## Akış Diyagramı

```mermaid
sequenceDiagram
    participant Client
    participant Gateway
    participant Proxy
    participant Upstream
    participant DB

    Client->>Gateway: POST /v1/chat/completions
    Note over Gateway: OpenAIHandler
    Gateway->>Gateway: fiberToHTTPHeaders()
    Gateway->>Gateway: API key auto-inject (gerekirse)
    Gateway->>Gateway: copyResponseHeaders()
    Gateway->>Proxy: Forward(method, targetURL, headers, body, timeout)
    Proxy->>Upstream: POST <OPENAI_BACKEND>/v1/chat/completions
    Upstream-->>Proxy: 200 OK + response body
    Proxy-->>Gateway: ForwardResult{StatusCode, Body, Headers}
    Gateway->>Gateway: copyResponseHeaders() (skip hop-by-hop)
    Gateway->>DB: go db.Create(logEntry) — fire-and-forget
    Gateway-->>Client: 200 OK + original response body
```

## Önemli Noktalar

- İstek body'si **olduğu gibi** iletilir (dönüşüm yok)
- Response header'ları kopyalanırken `Transfer-Encoding`, `Content-Length`, `Connection` atlanır
- Upstream hatasında client `502 Bad Gateway` alır
- DB loglama bir goroutine içinde çalışır, asla ana isteği bloke etmez