Refactor API structure: move chat functionality to v1 router, implement dependency injection for OpenAI client, and set up application state management

agent_api/core/llm.py

@@ -1,7 +0,0 @@
-from openai import OpenAI
-from .config import DEEPSEEK_API_KEY
-
-client = OpenAI(
-    api_key=DEEPSEEK_API_KEY,
-    base_url="https://api.deepseek.com"
-)

agent_api/main.py

@@ -1,84 +0,0 @@
-from fastapi import FastAPI
-from fastapi.middleware.cors import CORSMiddleware
-from pydantic import BaseModel
-from .core.llm import client
-
-app = FastAPI()
-
-app.add_middleware(
-    CORSMiddleware,
-    allow_origins=["*"],
-    allow_credentials=True,
-    allow_methods=["*"],
-    allow_headers=["*"],
-)
-
-class ChatRequest(BaseModel):
-    message: str
-    session_id: str | None = None
-
-
-def run_agent(message: str, session_id: str | None = None):
-    response = client.chat.completions.create(
-        model="deepseek-chat",
-        messages=[
-            {"role": "system", "content": "You are a helpful agent."},
-            {"role": "user", "content": message}
-        ]
-    )
-    return response.choices[0].message.content
-
-
-@app.get("/")
-def root():
-    return {"status": "ok"}
-
-
-@app.post("/chat")
-def chat(req: ChatRequest):
-    response = run_agent(req.message, req.session_id)
-
-    return {
-        "response": response,
-        "session_id": req.session_id
-    }
-
-
-@app.get("/v1/models")
-def list_models():
-    return {
-        "object": "list",
-        "data": [
-            {
-                "id": "agent-model",
-                "object": "model",
-                "created": 0,
-                "owned_by": "local-agent"
-            }
-        ]
-    }
-
-@app.get("/models")
-def legacy_models():
-    return list_models()
-
-@app.post("/chat/completions")
-def chat_completions(req: dict):
-    messages = req["messages"]
-    user_message = messages[-1]["content"]
-
-    response = run_agent(user_message)
-
-    return {
-        "id": "chatcmpl-local",
-        "object": "chat.completion",
-        "choices": [
-            {
-                "index": 0,
-                "message": {
-                    "role": "assistant",
-                    "content": response
-                }
-            }
-        ]
-    }

api/dependencies.py

@@ -0,0 +1,7 @@
+from fastapi import Request
+from openai import OpenAI
+
+
+def get_llm_client(request: Request) -> OpenAI:
+    """FastAPI dependency – returns the singleton OpenAI client from app.state."""
+    return request.app.state.llm_client

api/v1/chat.py

@@ -0,0 +1,70 @@
+from fastapi import APIRouter, Body, Depends
+from openai import OpenAI
+from pydantic import BaseModel
+
+from api.dependencies import get_llm_client
+
+router = APIRouter()
+
+
+class ChatRequest(BaseModel):
+    message: str
+    session_id: str | None = None
+
+
+def run_agent(client: OpenAI, message: str, session_id: str | None = None) -> str:
+    response = client.chat.completions.create(
+        model="deepseek-chat",
+        messages=[
+            {"role": "system", "content": "You are a helpful agent."},
+            {"role": "user", "content": message},
+        ],
+    )
+    return response.choices[0].message.content
+
+
+@router.get("/")
+def root():
+    return {"status": "ok"}
+
+
+@router.post("/chat")
+def chat(req: ChatRequest, client: OpenAI = Depends(get_llm_client)):
+    response = run_agent(client, req.message, req.session_id)
+    return {"response": response, "session_id": req.session_id}
+
+
+@router.get("/models")
+def list_models():
+    return {
+        "object": "list",
+        "data": [
+            {
+                "id": "agent-model",
+                "object": "model",
+                "created": 0,
+                "owned_by": "local-agent",
+            }
+        ],
+    }
+
+
+@router.post("/chat/completions")
+def chat_completions(
+    payload: dict = Body(...),
+    client: OpenAI = Depends(get_llm_client),
+):
+    messages = payload["messages"]
+    user_message = messages[-1]["content"]
+    response = run_agent(client, user_message)
+
+    return {
+        "id": "chatcmpl-local",
+        "object": "chat.completion",
+        "choices": [
+            {
+                "index": 0,
+                "message": {"role": "assistant", "content": response},
+            }
+        ],
+    }

core/config.py

@@ -2,6 +2,6 @@ from dotenv import load_dotenv
 from pathlib import Path
 import os
 
-load_dotenv(Path(__file__).resolve().parent.parent.parent / ".env")
+load_dotenv(Path(__file__).resolve().parent.parent / ".env")
 
 DEEPSEEK_API_KEY = os.getenv("DEEPSEEK_API_KEY")

core/llm.py

@@ -0,0 +1,9 @@
+from openai import OpenAI
+
+
+def create_client(api_key: str) -> OpenAI:
+    """Factory for an OpenAI-compatible client pointed at DeepSeek."""
+    return OpenAI(
+        api_key=api_key,
+        base_url="https://api.deepseek.com",
+    )

docker/Dockerfile

@@ -10,4 +10,4 @@ COPY . /Agents
 
 ENV PYTHONPATH=/Agents
 
-CMD ["uvicorn", "agent_api.main:app", "--host", "0.0.0.0", "--port", "8000"]
+CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000"]

main.py

@@ -0,0 +1,30 @@
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from api.v1.chat import router as v1_router
+from core.config import DEEPSEEK_API_KEY
+from core.llm import create_client
+
+
+app = FastAPI()
+
+# ---------------------------------------------------------------------------
+# Middleware
+# ---------------------------------------------------------------------------
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+# ---------------------------------------------------------------------------
+# Singletons (stored on app.state so every module can reach them via Depends)
+# ---------------------------------------------------------------------------
+app.state.llm_client = create_client(DEEPSEEK_API_KEY)
+
+# ---------------------------------------------------------------------------
+# Routers
+# ---------------------------------------------------------------------------
+app.include_router(v1_router, prefix="/v1")