rebuild(stage-10): deliver mentor and unified llm streaming

next/backend/features/mentor/routes.py

@@ -0,0 +1,104 @@
+from __future__ import annotations
+
+import json
+from collections.abc import Iterator
+from typing import Annotated
+
+from fastapi import APIRouter, Query, Request
+from fastapi.responses import StreamingResponse
+
+from backend.data.gateway import MarketDataUnavailable
+from backend.features.accounts.auth import (
+    AuthenticatedPrincipal,
+    SmartAccessPrincipal,
+    SmartWritePrincipal,
+)
+from backend.features.mentor.schemas import (
+    CountResponse,
+    MentorChatInput,
+    MentorPreferencesInput,
+)
+from backend.features.mentor.service import MentorError
+from backend.http.errors import AppError
+from backend.llm.gateway import LLMGatewayError
+
+router = APIRouter(prefix="/mentors", tags=["mentors"])
+
+
+@router.get("/setup", response_model=dict)
+def setup(
+    request: Request,
+    principal: AuthenticatedPrincipal,
+    trade_date: Annotated[str, Query(alias="date", min_length=10, max_length=10)],
+) -> dict:
+    return _call(request, "setup", principal, trade_date)
+
+
+@router.put("/preferences", response_model=dict)
+def save_preferences(
+    payload: MentorPreferencesInput,
+    request: Request,
+    principal: SmartWritePrincipal,
+) -> dict:
+    return _call(request, "save_preferences", principal, payload.order, payload.pinned)
+
+
+@router.get("/messages", response_model=list[dict])
+def messages(
+    request: Request,
+    principal: SmartAccessPrincipal,
+    mentor_id: Annotated[str, Query(min_length=1, max_length=100)],
+    trade_date: Annotated[str, Query(alias="date", min_length=10, max_length=10)],
+) -> list[dict]:
+    return _call(request, "messages", principal, mentor_id, trade_date)
+
+
+@router.delete("/messages", response_model=CountResponse)
+def clear_messages(
+    request: Request,
+    principal: SmartWritePrincipal,
+    mentor_id: Annotated[str, Query(min_length=1, max_length=100)],
+    trade_date: Annotated[str, Query(alias="date", min_length=10, max_length=10)],
+) -> CountResponse:
+    deleted = _call(request, "clear", principal, mentor_id, trade_date)
+    return CountResponse(deleted=deleted)
+
+
+@router.post("/chat")
+def chat(
+    payload: MentorChatInput,
+    request: Request,
+    principal: SmartWritePrincipal,
+) -> StreamingResponse:
+    prepared = _call(
+        request,
+        "prepare_chat",
+        principal,
+        payload.mentor_id,
+        payload.trade_date,
+        payload.question,
+    )
+
+    def body() -> Iterator[bytes]:
+        for event in request.app.state.container.mentor.stream_chat(prepared):
+            yield (json.dumps(event, ensure_ascii=False, separators=(",", ":")) + "\n").encode(
+                "utf-8"
+            )
+
+    return StreamingResponse(
+        body(),
+        media_type="application/x-ndjson",
+        headers={"Cache-Control": "no-cache, no-transform", "X-Accel-Buffering": "no"},
+    )
+
+
+def _call(request: Request, method: str, *args):
+    try:
+        return getattr(request.app.state.container.mentor, method)(*args)
+    except MentorError as exc:
+        raise AppError("mentor_unavailable", str(exc), 409) from exc
+    except MarketDataUnavailable as exc:
+        raise AppError("market_data_unavailable", str(exc), 503) from exc
+    except LLMGatewayError as exc:
+        status = 403 if exc.code in {"membership_required", "quota_exhausted"} else 503
+        raise AppError(exc.code, str(exc), status) from exc