使用Python从API提取特定JSON数据（Discord.py机器人问题）

我正在制作一个小型Discord.py机器人作为Python/API实验项目，目标是在Discord中按需打印API返回的特定数据。相关代码如下：

@client.command()
async def otherusers(ctx, player):
    rs = requests.get(apiLink + "/checkban?name=" + str(player))
    if rs.status_code == 200:
        rs = rs.json()
        embed = discord.Embed(title="Other users for" + str(player), description="""User is known as: """ + str(rs["usedNames"]))
        await ctx.send(embed=embed)

API返回示例如下：

{"id":1536171865,"avatar":"https://secure.download.dm.origin.com/production/avatar/prod/userAvatar/41472001/208x208.PNG","name":"_7cV","vban":{"A1 Army of One":{"bannedUntil":null,"reason":"ping >1000"}},"ingame":[],"otherNames":{"updateTimestamp":"2022-07-08T10:10:50.939000","usedNames":["ABCDE123","ABCDE1234","ABCDE12345","ABCDE1234567"]}}

当我将代码中的字符串改为str(rs["otherNames"])时可正常运行，但我只想提取用户名列表。若改为str(rs["usedNames"])，在Discord中调用命令时PyCharm会抛出错误：
discord.ext.commands.errors.CommandInvokeError: Command raised an exception: KeyError: 'usedNames'
恳请帮忙解决此问题。

核心原因 #

usedNames不是API返回JSON的顶级键，它嵌套在otherNames这个子对象里，直接访问rs["usedNames"]自然找不到对应的键，触发KeyError。

基础修正代码 #

调整键的访问路径，从rs["usedNames"]改为rs["otherNames"]["usedNames"]就能正确获取用户名列表：

@client.command()
async def otherusers(ctx, player):
    rs = requests.get(apiLink + "/checkban?name=" + str(player))
    if rs.status_code == 200:
        rs = rs.json()
        # 正确访问嵌套的usedNames列表
        used_names = rs["otherNames"]["usedNames"]
        # 将列表转为更易读的分行格式
        names_display = "\n".join(used_names)
        embed = discord.Embed(title=f"Other users for {player}", description=f"User is known as:\n{names_display}")
        await ctx.send(embed=embed)

进阶容错处理 #

为避免API返回结构变化（比如缺失otherNames或usedNames字段）导致命令崩溃，建议用dict.get()做容错处理：

@client.command()
async def otherusers(ctx, player):
    rs = requests.get(apiLink + "/checkban?name=" + str(player))
    if rs.status_code == 200:
        rs = rs.json()
        # 逐层获取字段，缺失时返回默认值
        other_names_data = rs.get("otherNames", {})
        used_names = other_names_data.get("usedNames", ["No alternative names found"])
        names_display = "\n".join(used_names)
        embed = discord.Embed(title=f"Other users for {player}", description=f"User is known as:\n{names_display}")
        await ctx.send(embed=embed)
    else:
        await ctx.send(f"Failed to fetch data. Status code: {rs.status_code}")

内容的提问来源于stack exchange，提问作者nOsfezodus