File size: 3,616 Bytes
5d50e27 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 | """e-Padoms FastAPI backend."""
import asyncio
import time
import uuid
from typing import Literal
from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from pydantic import BaseModel
from sse_starlette.sse import EventSourceResponse
from rag.pipeline import chat_stream
from rag.retriever import Retriever
app = FastAPI(title="e-Padoms API", version="1.0.0")
app.add_middleware(
CORSMiddleware,
allow_origins=["*"],
allow_methods=["*"],
allow_headers=["*"],
)
# In-memory conversation store: {conversation_id: {"messages": [...], "last_active": float}}
_conversations: dict[str, dict] = {}
CONVERSATION_TTL = 30 * 60 # 30 minutes
_retriever = Retriever()
SUGGESTIONS = [
"How do I register a SIA (limited liability company) in Latvia?",
"What taxes apply to Latvian startups?",
"What is the Startup Law and how do I qualify?",
"What is LIAA and how does it support startups?",
"Can a foreigner start a company in Latvia?",
"What is the difference between SIA and IK?",
]
def _expire_conversations():
now = time.time()
expired = [k for k, v in _conversations.items() if now - v["last_active"] > CONVERSATION_TTL]
for k in expired:
del _conversations[k]
class ChatRequest(BaseModel):
message: str
conversation_id: str | None = None
language: Literal["lv", "en", "auto"] = "auto"
@app.get("/api/health")
async def health():
return {"status": "ok", "documents_indexed": _retriever.count()}
@app.get("/api/suggestions")
async def suggestions():
return {"suggestions": SUGGESTIONS}
@app.post("/api/chat")
async def chat(req: ChatRequest):
if not req.message.strip():
raise HTTPException(status_code=400, detail="Message cannot be empty")
if len(req.message) > 2000:
raise HTTPException(status_code=400, detail="Message too long (max 2000 chars)")
_expire_conversations()
conv_id = req.conversation_id or str(uuid.uuid4())
if conv_id not in _conversations:
_conversations[conv_id] = {"messages": [], "last_active": time.time()}
conv = _conversations[conv_id]
conv["last_active"] = time.time()
history = conv["messages"]
# Add user message to history
history.append({"role": "user", "content": req.message})
# Keep last 10 messages (5 turns)
if len(history) > 10:
history[:] = history[-10:]
assistant_response_parts: list[str] = []
async def event_generator():
try:
async for event_data in chat_stream(req.message, history[:-1], req.language):
import json
parsed = json.loads(event_data)
if parsed["type"] == "token":
assistant_response_parts.append(parsed["content"])
yield {"data": event_data}
except Exception as e:
import json
yield {"data": json.dumps({"type": "error", "content": str(e)})}
finally:
# Store assistant's full response in history
full_response = "".join(assistant_response_parts)
if full_response:
history.append({"role": "assistant", "content": full_response})
if len(history) > 10:
history[:] = history[-10:]
return EventSourceResponse(
event_generator(),
headers={"X-Accel-Buffering": "no"},
)
from fastapi.staticfiles import StaticFiles
from pathlib import Path
_here = Path(__file__).parent
_frontend = _here / "frontend_dist"
app.mount("/", StaticFiles(directory=str(_frontend), html=True), name="frontend")
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