Ts-node : SyntaxError: 不能在模块外使用 import 语句答案

【问题标题】：Ts-node : SyntaxError: Cannot use import statement outside a moduleTs-node : SyntaxError: 不能在模块外使用 import 语句
【发布时间】：2020-12-31 08:03:36
【问题描述】：

我试图在项目中使用顶层，发现有必要将模块从 tscofnig 更改为 esnext 或 system，但由于某种原因，我的 ts-node 出现错误。而且我已经放了type:module 我试过用flag:--experimental-modules 但是报错还是不知道怎么解决。

package.json:

{
  "name": "micro-hr",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "type": "module",
  "scripts": {
    "commit": "git-cz",
    "build": "babel src --extensions \".js,.ts\" --out-dir dist --copy-files --no-copy-ignored",
    "start:dev": "ts-node-dev --experimental-modules --inspect --respawn --transpile-only --ignore-watch node_modules -r tsconfig-paths/register src/index.ts",
    "start:debug": "node start --debug --watch",
    "start:prod": "node dist/index.ts",
    "test": "jest",
    "lint": "eslint --fix",
    "lint2": "eslint \"{src,apps,libs,test}/**/*.ts\" --fix",
    "typeorm": "ts-node -r tsconfig-paths/register ./node_modules/typeorm/cli.js --config ./ormconfig.ts",
    "migration:generate": "ts-node ./node_modules/typeorm/cli.js migration:generate -n"
  },
  "devDependencies": {
    "@babel/cli": "^7.11.5",
    "@babel/core": "^7.11.5",
    "@babel/node": "^7.10.5",
    "@babel/preset-env": "^7.11.5",
    "@babel/preset-typescript": "^7.10.4",
    "@commitlint/cli": "^9.1.2",
    "@commitlint/config-conventional": "^9.1.2",
    "@types/bcryptjs": "^2.4.2",
    "@types/cookie-parser": "^1.4.2",
    "@types/cors": "^2.8.7",
    "@types/express": "^4.17.8",
    "@types/helmet": "^0.0.48",
    "@types/jest": "^26.0.13",
    "@types/node": "^14.6.4",
    "@types/pino": "^6.3.0",
    "@types/pino-http": "^5.0.5",
    "@types/supertest": "^2.0.10",
    "@typescript-eslint/eslint-plugin": "^4.0.1",
    "@typescript-eslint/parser": "^4.0.1",
    "babel-plugin-module-resolver": "^4.0.0",
    "commitizen": "^4.2.1",
    "cz-conventional-changelog": "^3.3.0",
    "eslint": "^7.8.1",
    "eslint-config-airbnb-base": "^14.2.0",
    "eslint-config-prettier": "^6.11.0",
    "eslint-config-standard": "^14.1.1",
    "eslint-import-resolver-typescript": "^2.3.0",
    "eslint-plugin-import": "^2.22.0",
    "eslint-plugin-node": "^11.1.0",
    "eslint-plugin-prettier": "^3.1.4",
    "eslint-plugin-promise": "^4.2.1",
    "eslint-plugin-standard": "^4.0.1",
    "husky": "^4.2.5",
    "jest": "^26.4.2",
    "pino-pretty": "^4.2.0",
    "prettier": "^2.1.1",
    "supertest": "^4.0.2",
    "ts-jest": "^26.3.0",
    "ts-node": "^9.0.0",
    "ts-node-dev": "^1.0.0-pre.62",
    "tsconfig-paths": "^3.9.0",
    "tscpaths": "^0.0.9",
    "typescript": "^4.0.2"
  },
  "dependencies": {
    "amqplib": "^0.6.0",
    "assert": "^2.0.0",
    "bcryptjs": "^2.4.3",
    "class-transformer": "^0.3.1",
    "cors": "^2.8.5",
    "dotenv": "^8.2.0",
    "envalid": "^6.0.2",
    "express": "^4.17.1",
    "extendable-error": "^0.1.7",
    "helmet": "^4.1.0",
    "nabbitmq": "^1.0.0",
    "pg": "^8.3.3",
    "pino": "^6.5.1",
    "pino-http": "^5.2.0",
    "reflect-metadata": "^0.1.13",
    "spt-rabbit-helpers": "^1.0.6",
    "tsyringe": "^4.3.0",
    "typeorm": "^0.2.25"
  },
  "config": {
    "commitizen": {
      "path": "cz-conventional-changelog"
    }
  }
}

tsconfig:

{
  "compilerOptions": {
    "target": "es2020",
    "module": "esnext",
    "allowJs": true,
    "outDir": "./dist",
    "rootDir": "./src",
    "strict": true,
    "strictPropertyInitialization": false,
    "moduleResolution": "node",
    "baseUrl": "./src",
    "allowSyntheticDefaultImports": true,
    "esModuleInterop": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "forceConsistentCasingInFileNames": true,
    "noImplicitAny": true,
    "typeRoots": ["node_modules/@types", "@types"]
  },
  "include": ["src", "__tests__"],
  "exclude": ["node_modules"]
}

主要：

import 'reflect-metadata';
import express from 'express';
import { RabbitServer } from 'spt-rabbit-helpers';
import validateEnv from 'utils/validateEnvs';
import {
  RabbitMqConnectionFactory,
  ConsumerFactory,
  PublisherFactory,
  RabbitMqConnection,
} from 'nabbitmq';
import { container, singleton } from 'tsyringe';

const factory = new RabbitMqConnectionFactory();
factory.setUri('amqp://localhost:5672');
const ConsumerConnection = await factory.newConnection();
const PublisherConnection = await factory.newConnection();
container.registerInstance('Consumer_Connection', ConsumerConnection);
container.registerInstance('Publisher_Connection', PublisherConnection);

【问题讨论】：

你解决过这个问题吗？为什么要用顶级的await需要javasript的硕士学位？

标签： typescript ts-node

【解决方案1】：

要运行 ts-node（或普通节点），您需要使用 "module": "commonjs", "target": "ES2017"，否则 import/export 语句会被非法放置在 IIFE 中。

所以我建议使用另一个名为 node.tsconfig.json 的文件，其内容如下：

{
    "extends": "./tsconfig.json",
    "compilerOptions": {
        "target": "ES2017" // For NodeJS 8 compat, see https://www.typescriptlang.org/tsconfig#target for more info
    }
}

然后用--project ./node.tsconfig.json运行ts-node

【讨论】：

需要注意的是ts-node命令中的项目arg必须在脚本名之前。例如ts-node --project ./node.tsconfig.json your-script.ts
显然 ts-node 也接受格式{"ts-node": {"compilerOptions": { ... } } } ...在主tsconfig.json

【解决方案2】：

我遇到了同样的问题，我通过将tsconfig.json 中的module 更改为commonjs 并删除module 中的module 键来修复它：

// tsconfig.json
{
    "module": "CommonJS",
}

【讨论】：

这消除了使用顶级等待的能力，这是 OP 试图完成的

【解决方案3】：

如果你使用React，则不能为TypeScript设置“commonjs”。

tsconfig.json

{
    "compilerOptions": {
        "module": "esnext"
    }
}

package.json

{
    "type": "module",
    "scripts": {
        "tsnode": "node --loader ts-node/esm --no-warnings"
    },
    "dependencies": {
        "ts-node": "^10.4.0"
    }
}

hello.ts

import * as os from "os"
console.log("os", os);

TypeScript 文件的两种执行方式：

node --loader ts-node/esm --no-warnings hello.ts
npm run tsnode hello.ts

【讨论】：