NerWelcomeBot.py

import simplematrixbotlib as botlib
from nio import RoomMemberEvent, rooms
from yaml import safe_load
from re import match

with open("config.yaml", "r", encoding="utf8") as config_file:
    config = safe_load(config_file)

creds = botlib.Creds(config["target_server"], config["bot_username"], access_token=config["access_token"], session_stored_file=config["session_file"])
bot = botlib.Bot(creds)


# "m.room.member"
@bot.listener.on_custom_event(RoomMemberEvent)
async def welcome(room: rooms.MatrixRoom, message: RoomMemberEvent):
    if room.room_id == config["target_room_id"] and message.membership == "join" and message.prev_content is None:
        # someone joined!
        new_user_id = message.state_key
        new_user_name = match(r"@(.*):chat.neboer.site", new_user_id).group(1)
        print(new_user_name + " join in!")
        await bot.api.send_markdown_message(room.room_id, f"欢迎[{new_user_name}](https://matrix.to/#/@{new_user_name}:chat.neboer.site)加入NerChat!！请访问 neboer.site/nerchat 阅读文档！")

bot.run()