run_ui.py

from datetime import timedelta
import os
import secrets
import sys
import time
import socket
import struct
from functools import wraps
import threading
import signal
from typing import override
from flask import Flask, request, Response, session
from flask_basicauth import BasicAuth
import initialize
from python.helpers import errors, files, git, mcp_server
from python.helpers.files import get_abs_path
from python.helpers import runtime, dotenv, process
from python.helpers.extract_tools import load_classes_from_folder
from python.helpers.api import ApiHandler
from python.helpers.print_style import PrintStyle


# Set the new timezone to 'UTC'
os.environ["TZ"] = "UTC"
# Apply the timezone change
if hasattr(time, 'tzset'):
    time.tzset()

# initialize the internal Flask server
webapp = Flask("app", static_folder=get_abs_path("./webui"), static_url_path="/")
webapp.secret_key = os.getenv("FLASK_SECRET_KEY") or secrets.token_hex(32)
webapp.config.update(
    JSON_SORT_KEYS=False,
    SESSION_COOKIE_NAME="session_" + runtime.get_runtime_id(),  # bind the session cookie name to runtime id to prevent session collision on same host
    SESSION_COOKIE_SAMESITE="Strict",
    SESSION_PERMANENT=True,
    PERMANENT_SESSION_LIFETIME=timedelta(days=1)
)


lock = threading.Lock()

# Set up basic authentication for UI and API but not MCP
basic_auth = BasicAuth(webapp)


def is_loopback_address(address):
    loopback_checker = {
        socket.AF_INET: lambda x: struct.unpack("!I", socket.inet_aton(x))[0]
        >> (32 - 8)
        == 127,
        socket.AF_INET6: lambda x: x == "::1",
    }
    address_type = "hostname"
    try:
        socket.inet_pton(socket.AF_INET6, address)
        address_type = "ipv6"
    except socket.error:
        try:
            socket.inet_pton(socket.AF_INET, address)
            address_type = "ipv4"
        except socket.error:
            address_type = "hostname"

    if address_type == "ipv4":
        return loopback_checker[socket.AF_INET](address)
    elif address_type == "ipv6":
        return loopback_checker[socket.AF_INET6](address)
    else:
        for family in (socket.AF_INET, socket.AF_INET6):
            try:
                r = socket.getaddrinfo(address, None, family, socket.SOCK_STREAM)
            except socket.gaierror:
                return False
            for family, _, _, _, sockaddr in r:
                if not loopback_checker[family](sockaddr[0]):
                    return False
        return True


def requires_api_key(f):
    @wraps(f)
    async def decorated(*args, **kwargs):
        valid_api_key = dotenv.get_dotenv_value("API_KEY")
        if api_key := request.headers.get("X-API-KEY"):
            if api_key != valid_api_key:
                return Response("API key required", 401)
        elif request.json and request.json.get("api_key"):
            api_key = request.json.get("api_key")
            if api_key != valid_api_key:
                return Response("API key required", 401)
        else:
            return Response("API key required", 401)
        return await f(*args, **kwargs)

    return decorated


# allow only loopback addresses
def requires_loopback(f):
    @wraps(f)
    async def decorated(*args, **kwargs):
        if not is_loopback_address(request.remote_addr):
            return Response(
                "Access denied.",
                403,
                {},
            )
        return await f(*args, **kwargs)

    return decorated


# require authentication for handlers
def requires_auth(f):
    @wraps(f)
    async def decorated(*args, **kwargs):
        user = dotenv.get_dotenv_value("AUTH_LOGIN")
        password = dotenv.get_dotenv_value("AUTH_PASSWORD")
        if user and password:
            auth = request.authorization
            if not auth or not (auth.username == user and auth.password == password):
                return Response(
                    "Could not verify your access level for that URL.\n"
                    "You have to login with proper credentials",
                    401,
                    {"WWW-Authenticate": 'Basic realm="Login Required"'},
                )
        return await f(*args, **kwargs)

    return decorated


def csrf_protect(f):
    @wraps(f)
    async def decorated(*args, **kwargs):
        token = session.get("csrf_token")
        header = request.headers.get("X-CSRF-Token")
        cookie = request.cookies.get("csrf_token_" + runtime.get_runtime_id())
        sent = header or cookie
        if not token or not sent or token != sent:
            return Response("CSRF token missing or invalid", 403)
        return await f(*args, **kwargs)

    return decorated


# handle default address, load index
@webapp.route("/", methods=["GET"])
@requires_auth
async def serve_index():
    gitinfo = None
    try:
        gitinfo = git.get_git_info()
    except Exception:
        gitinfo = {
            "version": "unknown",
            "commit_time": "unknown",
        }
    return files.read_file(
        "./webui/index.html",
        version_no=gitinfo["version"],
        version_time=gitinfo["commit_time"],
    )


def run():
    PrintStyle().print("Initializing framework...")

    # Suppress only request logs but keep the startup messages
    from werkzeug.serving import WSGIRequestHandler
    from werkzeug.serving import make_server
    from werkzeug.middleware.dispatcher import DispatcherMiddleware
    from a2wsgi import ASGIMiddleware, WSGIMiddleware

    PrintStyle().print("Starting server...")

    class NoRequestLoggingWSGIRequestHandler(WSGIRequestHandler):
        def log_request(self, code="-", size="-"):
            pass  # Override to suppress request logging

    # Get configuration from environment
    port = runtime.get_web_ui_port()
    host = (
        runtime.get_arg("host") or dotenv.get_dotenv_value("WEB_UI_HOST") or "localhost"
    )
    server = None

    def register_api_handler(app, handler: type[ApiHandler]):
        name = handler.__module__.split(".")[-1]
        instance = handler(app, lock)

        async def handler_wrap():
            return await instance.handle_request(request=request)

        if handler.requires_loopback():
            handler_wrap = requires_loopback(handler_wrap)
        if handler.requires_auth():
            handler_wrap = requires_auth(handler_wrap)
        if handler.requires_api_key():
            handler_wrap = requires_api_key(handler_wrap)
        if handler.requires_csrf():
            handler_wrap = csrf_protect(handler_wrap)

        app.add_url_rule(
            f"/{name}",
            f"/{name}",
            handler_wrap,
            methods=handler.get_methods(),
        )

    # initialize and register API handlers
    handlers = load_classes_from_folder("python/api", "*.py", ApiHandler)
    for handler in handlers:
        register_api_handler(webapp, handler)

    # add the webapp and mcp to the app
    app = DispatcherMiddleware(
        webapp,
        {
            "/mcp": ASGIMiddleware(app=mcp_server.DynamicMcpProxy.get_instance()),  # type: ignore
        },
    )
    PrintStyle().debug("Registered middleware for MCP and MCP token")

    PrintStyle().debug(f"Starting server at {host}:{port}...")

    server = make_server(
        host=host,
        port=port,
        app=app,
        request_handler=NoRequestLoggingWSGIRequestHandler,
        threaded=True,
    )
    process.set_server(server)
    server.log_startup()

    # Start init_a0 in a background thread when server starts
    # threading.Thread(target=init_a0, daemon=True).start()
    init_a0()

    # run the server
    server.serve_forever()


def init_a0():
    # initialize contexts and MCP
    init_chats = initialize.initialize_chats()
    initialize.initialize_mcp()
    # start job loop
    initialize.initialize_job_loop()
    # preload
    initialize.initialize_preload()

    # only wait for init chats, otherwise they would seem to dissapear for a while on restart
    init_chats.result_sync()


# run the internal server
if __name__ == "__main__":
    runtime.initialize()
    dotenv.load_dotenv()
    run()