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+# 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