如何将SlashCommandBuilder选项存至独立JS文件并解决调用报错

问题场景 #

原本在SlashCommandBuilder中直接编写选项代码可正常运行：

.addStringOption((option) => option
    .setName('city')
    .setDescription('In which city are you currently based from?')
    .addChoices(
        { name: 'City 1', value: 'City-1-Example' },
        { name: 'City 2', value: 'City-2-Example' }
    )
    .setRequired(true)
)

为了统一管理选项，将选项抽离到options.js：

export const options = {
    city: [
        { name: 'City 1', value: 'City-1-Example' },
        { name: 'City 2', value: 'City-2-Example' }
    ],
    optionsForAnotherCommand: [/* ... */]
}

但调用时出现错误：

errors: [[ 0, ValidationError: Expected the value to not be an array ...

错误原因 #

Discord.js的addChoices方法要求传入多个独立的键值对对象参数，而非单个数组。直接传递options.city会把整个数组作为单个参数传入，不符合方法的参数格式要求。

快速修复 #

使用ES6扩展运算符（...）将数组展开为多个独立参数即可解决：

.addStringOption((option) => option
    .setName('city')
    .setDescription('In which city are you currently based from?')
    .addChoices(...options.city) // 用...展开数组
    .setRequired(true)
)

更规范的选项管理方案 #

1. 按功能/命令拆分选项文件 #

避免单个options.js文件过大，按通用选项、特定命令选项拆分存储：

// options/cityChoices.js
export const cityChoices = [
    { name: 'City 1', value: 'City-1-Example' },
    { name: 'City 2', value: 'City-2-Example' }
];

// options/userTypeChoices.js
export const userTypeChoices = [/* ... */];

2. 封装完整选项构建函数 #

将选项的名称、描述、必填性、选项值等完整配置封装成函数，直接在命令中调用，减少重复代码：

// options/optionBuilders.js
import { SlashCommandStringOption } from 'discord.js';
import { cityChoices } from './cityChoices.js';

export const buildCityOption = () => 
    new SlashCommandStringOption()
        .setName('city')
        .setDescription('In which city are you currently based from?')
        .addChoices(...cityChoices)
        .setRequired(true);

调用时只需一行代码：

.addStringOption(buildCityOption())

3. 配置文件驱动 #

如果选项需要频繁修改或从外部数据源同步，可以将选项存储在JSON/YAML配置文件中，通过工具函数动态加载：

// config/cityChoices.json
[
    {"name": "City 1", "value": "City-1-Example"},
    {"name": "City 2", "value": "City-2-Example"}
]

加载并使用：

import cityChoices from '../config/cityChoices.json' assert { type: 'json' };

// 在命令中
.addStringOption((option) => option
    .setName('city')
    .setDescription('In which city are you currently based from?')
    .addChoices(...cityChoices)
    .setRequired(true)
)

内容的提问来源于stack exchange，提问作者Cif