迷宫求解Bot重复发送消息问题及嵌套on_message失效求助

我正在开发一个用于破解另一个Bot迷宫的Bot，需通过!wall、!step等指令进行移动，每条指令都会收到对应响应。目前该Bot可正常响应消息，但在转向操作时会同时发送两条消息，原因是仍在使用旧的响应消息，从而产生消息插入间隙。我尝试通过嵌套async def on_message(self, ctx)来更新消息，但并未生效。

当前使用的代码：

async def on_message(self, ctx):
        message_input = ctx.content
        message_content = " ".join(line.strip() for line in message_input.splitlines())
        time.sleep(1)
        #MOVEMENT
        #keep right
        await ctx.channel.send("!turn right")
        await ctx.channel.send("!wall")
        async def on_message(self, ctx):
            message_input = ctx.content
            message_content = " ".join(line.strip() for line in message_input.splitlines())
            #move if no wall in front
            if message_content == f"__**Wall**__ You can move forward.":
                return await ctx.channel.send("!step")
            #if wall is in front, turn forward again and check for walls
            if message_content == f"__**Wall**__ There is a wall in front of you.":
                await ctx.channel.send("!turn left")
                await ctx.channel.send("!wall")
                async def on_message(self, ctx):
                    message_input = ctx.content
                    message_content = " ".join(line.strip() for line in message_input.splitlines())
                    #if wall is still in front of me, turn around and go back
                    if message_content == f"__**Wall**__ There is a wall in front of you.":
                        await ctx.channel.send("!turn right")
                        await ctx.channel.send("!turn right")
                        await ctx.channel.send("!step")
                    #if no wall is in front of me, keep going forward
                    else:
                        await ctx.channel.send("!step")

解决办法 #

1. 移除嵌套的on_message函数 #

嵌套定义事件处理函数完全无效，事件系统不会识别内部的on_message。你需要用状态机跟踪Bot的操作阶段，而不是嵌套监听。

2. 实现状态管理 #

给Bot添加状态变量，记录当前执行的操作阶段，根据状态处理对应响应：

import asyncio

class MazeBot:
    def __init__(self):
        self.current_state = "idle"  # 初始状态：空闲
        # 提取响应文本为常量，避免硬编码
        self.WALL_CAN_MOVE = "__**Wall**__ You can move forward."
        self.WALL_BLOCKED = "__**Wall**__ There is a wall in front of you."

    async def on_message(self, ctx):
        message_input = ctx.content
        message_content = " ".join(line.strip() for line in message_input.splitlines())

        if self.current_state == "idle":
            # 初始操作：右转并检查墙体
            await asyncio.sleep(1)  # 替换同步sleep为异步延迟
            await ctx.channel.send("!turn right")
            await ctx.channel.send("!wall")
            self.current_state = "waiting_first_wall"

        elif self.current_state == "waiting_first_wall":
            if message_content == self.WALL_CAN_MOVE:
                await ctx.channel.send("!step")
                self.current_state = "idle"
            elif message_content == self.WALL_BLOCKED:
                await ctx.channel.send("!turn left")
                await ctx.channel.send("!wall")
                self.current_state = "waiting_second_wall"

        elif self.current_state == "waiting_second_wall":
            if message_content == self.WALL_BLOCKED:
                await ctx.channel.send("!turn right")
                await ctx.channel.send("!turn right")
                await ctx.channel.send("!step")
            else:
                await ctx.channel.send("!step")
            self.current_state = "idle"

3. 替换同步阻塞的time.sleep #

time.sleep(1)会阻塞整个事件循环，导致Bot无法及时处理其他消息。改用asyncio.sleep(1)实现异步延迟，不影响Bot的其他操作。

4. 优化响应文本判断 #

把迷宫Bot的响应文本提取为类属性常量，避免重复硬编码，后续修改响应格式时只需更新常量即可。

内容的提问来源于stack exchange，提问作者Sampler