feat: Initialize FastAPI AI Gateway project structure with authentication, module management, and LLM API routing.

app/api/endpoints/openai.py

@@ -0,0 +1,46 @@
+from fastapi import APIRouter, Depends, Request
+from app.api.deps import get_api_key
+from app.core.limiter import limiter
+from app.core.config import settings
+from pydantic import BaseModel
+from openai import AsyncOpenAI
+import asyncio
+
+router = APIRouter()
+
+class LLMRequest(BaseModel):
+    prompt: str
+    context: str = ""
+
+# Initialize Async client
+client = None
+if settings.OPENAI_API_KEY and settings.OPENAI_API_KEY != "your-openai-api-key":
+    client = AsyncOpenAI(api_key=settings.OPENAI_API_KEY)
+
+@router.post("/chat")
+@limiter.limit(settings.RATE_LIMIT)
+async def openai_chat(
+    request: Request,
+    chat_data: LLMRequest,
+    api_key: str = Depends(get_api_key)
+):
+    try:
+        if not client:
+             return {
+                "status": "mock",
+                "model": "openai",
+                "response": f"MOCK: OpenAI response to '{chat_data.prompt}'"
+            }
+
+        # Perform Async call to OpenAI
+        response = await client.chat.completions.create(
+            model="gpt-3.5-turbo",
+            messages=[{"role": "user", "content": chat_data.prompt}]
+        )
+        return {
+            "status": "success",
+            "model": "openai",
+            "response": response.choices[0].message.content
+        }
+    except Exception as e:
+        return {"status": "error", "detail": str(e)}