scm-harmonic-cmts-admin/routers/terminal.py

107 lines
4.1 KiB
Python
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

import asyncio
import asyncssh
from fastapi import APIRouter, WebSocket, WebSocketDisconnect
from logger import get_logger
logger = get_logger("app.ssh")
router = APIRouter()
@router.websocket("/ws/terminal")
async def websocket_terminal(websocket: WebSocket, host: str, username: str, password: str):
await websocket.accept()
conn = None
process = None
ws_task = None
ssh_task = None
try:
# 建立連線
conn = await asyncssh.connect(host, username=username, password=password, known_hosts=None)
# 💡 關鍵修復:使用 term_size 參數來指定寬高 (width, height)
process = await conn.create_process(
term_type='xterm-256color',
term_size=(80, 24), # 正確的 asyncssh 參數格式
encoding=None
)
async def forward_to_ws():
try:
while True:
data_bytes = await process.stdout.read(8192)
if not data_bytes:
logger.debug("設備端主動關閉了 stdout 通道")
break
safe_text = data_bytes.decode('utf-8', errors='replace')
await websocket.send_text(safe_text)
except asyncio.CancelledError:
pass
except Exception as e:
logger.error("❌ [WS Forward Error] 讀取設備畫面時發生錯誤", exc_info=True)
async def forward_to_ssh():
try:
while True:
data_text = await websocket.receive_text()
data_bytes = data_text.encode('utf-8')
# 攔截 xterm.js 預設的 DEL (\x7f),轉換為 BS (\x08)
if b'\x7f' in data_bytes:
data_bytes = data_bytes.replace(b'\x7f', b'\x08')
process.stdin.write(data_bytes)
await process.stdin.drain()
except WebSocketDisconnect:
# 主動拋出,讓外層捕捉以進行資源回收
# raise
# 🌟 修正:不要再 raise 拋出去了,直接 return 結束任務,讓外層自然回收
logger.debug("前端 WebSocket 正常斷開 (使用者重整或關閉網頁)")
return
except asyncio.CancelledError:
pass
except Exception as e:
logger.error("❌ [SSH Forward Error] 寫入指令到設備時發生錯誤", exc_info=True)
ws_task = asyncio.create_task(forward_to_ws())
ssh_task = asyncio.create_task(forward_to_ssh())
done, pending = await asyncio.wait(
[ws_task, ssh_task],
return_when=asyncio.FIRST_COMPLETED
)
for task in pending:
task.cancel()
except WebSocketDisconnect:
logger.debug("WebSocket 正常斷線,正在終止背景任務...")
if ws_task and not ws_task.done():
ws_task.cancel()
if ssh_task and not ssh_task.done():
ssh_task.cancel()
except Exception as e:
err_str = str(e)
error_msg = f"\r\n\x1b[31mSSH Connection Error: {err_str}\x1b[0m\r\n"
try:
# 先把錯誤印在終端機畫面上
await websocket.send_text(error_msg)
# 🌟 關鍵修復:使用自訂斷線碼 4001並附上錯誤原因 (WebSocket 規範 reason 最長 123 bytes)
safe_reason = err_str[:120] if err_str else "Authentication or Connection Failed"
await websocket.close(code=4001, reason=safe_reason)
except:
pass
logger.error("❌ [Connection Error] 建立連線或執行過程中發生錯誤", exc_info=True)
return # 🌟 提早結束,避免下方的 finally 再次執行 close 導致報錯
finally:
# 🌟 確保 process 與 conn 絕對被關閉,防止 Memory Leak
if process:
process.close()
if conn:
conn.close()
try:
await websocket.close()
except:
pass