运行amplify serve时@aws-amplify/core报TypeScript错误的解决咨询

本地运行React.js/TypeScript应用的amplify serve命令时，出现Amplify库相关的TypeScript错误，相关配置及错误信息如下：

依赖版本（package.json片段） #

{
  "dependencies": 
  {
    "@aws-amplify/core": "^5.1.12",
    "@aws-amplify/ui-react": "^4.6.0",
    "@aws-amplify/ui-react-storage": "^1.1.0",
    "aws-amplify": "^5.1.3",
    "typescript": "^3.8.3"
  }
}

tsconfig.json配置 #

{
  "compilerOptions": {
    "target": "es5",
    "lib": ["es6", "dom", "dom.iterable", "esnext" ],
    "allowJs": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "forceConsistentCasingInFileNames": true,
    "noFallthroughCasesInSwitch": true,
    "module": "esnext",
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "isolatedModules": true,
    "noEmit": true,
    "strict": true,
    "noImplicitAny": true,
    "noImplicitThis": true,
    "strictNullChecks": true,
    "plugins": [{ "name": "typescript-plugin-css-modules" }],
    "jsx": "react"
  },
  "include": ["src"],
  "exclude": ["node_modules"]
}

出现的TypeScript错误 #

错误1 #

ERROR in node_modules/@aws-amplify/core/src/Hub.ts:82:34
TS7015: Element implicitly has an 'any' type because index expression is not of type 'number'.
    80 |                        this.patterns = [...this.patterns.filter(x => x !== pattern)];
    81 |                } else {
  > 82 |                        const holder = this.listeners[channel];
       |                                                      ^^^^^^^
    83 |                        if (!holder) {
    84 |                                logger.warn(`No listeners for ${channel}`);
    85 |                                return;

错误2 #

ERROR in node_modules/@aws-amplify/core/src/Logger/ConsoleLogger.ts:33:10

TS2564: Property '_config' has no initializer and is not definitely assigned in the constructor.
    31 |    level: LOG_TYPE | string;
    32 |    private _pluggables: LoggingProvider[];
  > 33 |    private _config: object;
       |            ^^^^^^^
    34 |
    35 |    /**
    36 |     * @constructor

错误3 #

ERROR in node_modules/@aws-amplify/core/src/Logger/ConsoleLogger.ts:80:4

TS2322: Type 'null' is not assignable to type 'string'.
    78 |        let logger_level_name = this.level;
    79 |        if (ConsoleLogger.LOG_LEVEL) {
  > 80 |            logger_level_name = ConsoleLogger.LOG_LEVEL;
       |            ^^^^^^^^^^^^^^^^^
    81 |        }
    82 |        if (typeof (<any>window) !== 'undefined' && (<any>window).LOG_LEVEL) {
    83 |            logger_level_name = (<any>window).LOG_LEVEL;

• TypeScript版本不兼容：使用的TypeScript 3.8.3版本过旧，Amplify v5+的类型定义基于更高版本TS（至少4.x）编写，旧版本无法正确解析新类型规则。
• Amplify库类型缺陷：部分Amplify源码存在类型不严谨问题，比如未明确索引类型、属性未初始化、null赋值给非null变量，在TS严格模式下触发错误。
• TS严格模式冲突：tsconfig.json开启了strict: true（包含noImplicitAny、strictNullChecks等规则），放大了Amplify类型定义的问题。

1. 升级TypeScript版本（推荐） #

这是最根本的解决办法，升级到与Amplify v5兼容的TS版本（推荐4.9+）：

npm install typescript@^4.9.0 --save-dev
# 或用yarn
yarn add typescript@^4.9.0 --dev

2. 确保skipLibCheck生效 #

虽然配置里已经设了skipLibCheck: true，但可简化exclude配置确保其生效：

"exclude": ["node_modules"]

该选项会让TS跳过第三方库的类型检查，直接忽略库内部的类型错误。

3. 升级Amplify依赖到最新稳定版 #

Amplify团队会持续修复类型问题，升级到v5最新兼容版本：

npm install aws-amplify@^5.3.0 @aws-amplify/core@^5.4.0 @aws-amplify/ui-react@^4.8.0 @aws-amplify/ui-react-storage@^1.3.0 --save
# 或用yarn
yarn upgrade aws-amplify@^5.3.0 @aws-amplify/core@^5.4.0 @aws-amplify/ui-react@^4.8.0 @aws-amplify/ui-react-storage@^1.3.0

4. 临时忽略特定错误（不推荐长期使用） #

若暂时无法升级，可临时关闭部分TS严格规则：

"compilerOptions": {
  // 其他配置保持不变
  "noImplicitAny": false,
  "strictPropertyInitialization": false,
  "strictNullChecks": false
}

注意：关闭严格规则会降低TS类型检查能力，可能引入潜在问题，仅作临时方案。

内容的提问来源于stack exchange，提问作者Raystorm