无法在mikroorm中使用模块外部的导入语句。

Question

我在postgresql和nodejs中使用Mikro-orm，运行项目时会出现此错误:无法在模块外使用导入语句。我不知道怎么解释到底是怎么回事--我认为问题是在tsconfig.ts中，我正在使用带有postgresql和nodejs的Mikro-orm，这个错误在我运行我的项目时会出现:不能在模块之外使用导入语句。我不知道怎么解释这是怎么回事，我认为问题出在tsconfig.json

误差

import { Migration } from '@mikro-orm/migrations';
^^^^^^

SyntaxError: Cannot use import statement outside a module
    at wrapSafe (internal/modules/cjs/loader.js:979:16)
    at Module._compile (internal/modules/cjs/loader.js:1027:27)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
    at Module.load (internal/modules/cjs/loader.js:928:32)
    at Function.Module._load (internal/modules/cjs/loader.js:769:14)
    at Module.require (internal/modules/cjs/loader.js:952:19)
    at require (internal/modules/cjs/helpers.js:88:18)
    at Migrator.resolve (/home/logorcehab/Documents/Dev/altevibes/altevibe-server/node_modules/@mikro-orm/migrations/Migrator.js:141:27)
    at Object.customResolver (/home/logorcehab/Documents/Dev/altevibes/altevibe-server/node_modules/@mikro-orm/migrations/Migrator.js:43:44)
    at Migration.migration (/home/logorcehab/Documents/Dev/altevibes/altevibe-server/node_modules/umzug/lib/migration.js:60:38)
    at /home/logorcehab/Documents/Dev/altevibes/altevibe-server/node_modules/umzug/lib/migration.js:121:37
    at Generator.next (<anonymous>)
    at asyncGeneratorStep (/home/logorcehab/Documents/Dev/altevibes/altevibe-server/node_modules/umzug/lib/migration.js:9:103)
    at _next (/home/logorcehab/Documents/Dev/altevibes/altevibe-server/node_modules/umzug/lib/migration.js:11:194)
    at /home/logorcehab/Documents/Dev/altevibes/altevibe-server/node_modules/umzug/lib/migration.js:11:364
    at new Promise (<anonymous>)

mikro-orm.config.ts

import { MikroORM } from "@mikro-orm/core";
import { __PROD__ } from "./constants";
import { Users } from "./entities/Users";
import path from "path"
export default {
  migrations: {
    tableName: 'mikro_orm_migrations', // migrations table name
    path:'./src/migrations', // path to folder with migration files
    pattern: /^[\w-]+\d+\.[t]s$/, // how to match migration files
    transactional: true, // run each migration inside transaction
    disableForeignKeys: true, // try to disable foreign_key_checks (or equivalent)
    allOrNothing: true, // run all migrations in current batch in master transaction
    emit: 'ts', // migration generation mode
  },
  entities:[Users],
    dbName:'altevibes',
    user:'dev_main',
    password:'login@Logout64',
    type:'postgresql',
    debug: !__PROD__
} as Parameters<typeof MikroORM.init>[0];

index.ts

import {MikroORM } from "@mikro-orm/core"
import 'reflect-metadata'
import {__PROD__} from "./constants"
//import { Post } from "./entities/Post"
import express from 'express'
import { ApolloServer } from 'apollo-server-express'
import { buildSchema } from 'type-graphql'
//import { UsersResolver } from "./resolvers/user"
import { Users } from "./entities/Users"
import microConfig from './mikro-orm.config'
const main = async () => {
  const orm = await MikroORM.init(microConfig)
  await orm.getMigrator().up()
  const posts = orm.em.create(Users, {username: 'mfn'})
  await orm.em.persistAndFlush(posts)
}

console.log("Hello World")

main().catch((e)=>{console.log(e)});

package.json

{
  "name": "altevibe-server",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "watch": "tsc -w",
    "dev": "nodemon dist/src/index.js",
    "start": "node dist/src/index.js",
    "start2": "ts-node src/index.ts",
    "create:migration": "mikro-orm migration:create"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@mikro-orm/cli": "^4.3.4",
    "@mikro-orm/core": "^4.3.4",
    "@mikro-orm/migrations": "^4.3.4",
    "@mikro-orm/mongodb": "^4.3.4",
    "@mikro-orm/postgresql": "^4.3.4",
    "@sindresorhus/is": "^4.0.0",
    "apollo-server-express": "^2.19.1",
    "argon2": "^0.27.1",
    "class-validator": "^0.12.2",
    "express": "^4.17.1",
    "graphql": "^15.4.0",
    "mikro-orm": "^4.3.4",
    "mongodb": "^3.6.3",
    "nodemon": "^2.0.6",
    "pg": "^8.5.1",
    "reflect-metadata": "^0.1.13",
    "run-rs": "^0.7.4",
    "ts-node": "^9.1.1",
    "type-graphql": "^1.1.1"
  },
  "mikro-orm": {
    "useTsNode": false,
    "configPaths": [
      "./src/mikro-orm.config.ts",
      "./dist/src/mikro-orm.config.js"
    ]
  },
  "devDependencies": {
    "@types/express": "^4.17.9",
    "typescript": "^4.1.3"
  }
}

tsconfig.json

{
  "compilerOptions": {
    "target": "es6",
    "lib": [
      "es6"
    ],
    "sourceMap": true,
    "outDir": "./dist/src",
    "moduleResolution": "node",
    "removeComments": true,
    "noImplicitAny": true,
    "strictNullChecks": true,
    "strictFunctionTypes": true,
    "noImplicitThis": true,
    "module": "commonjs",
    "noUnusedParameters": true,
    "noImplicitReturns": true,
    "esModuleInterop": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "resolveJsonModule": true,
    "baseUrl": "."
  },
  "exclude": [
    "node_modules"
  ],
  "include": [
    "./src/**/*.tsx",
    "./src/**/*.ts"
  ]
}

Answer 1

我也遇到了同样的问题，并通过在root中创建一个扩展的tsconfig.mikro-orm.json文件并将其添加到其中来解决这个问题。

// tsconfig.mikro-orm.json
{
  "extends": "./tsconfig.json",
  "compilerOptions": {
    "module": "commonjs" // this line is important 
  }
}

// in package.json file add 
"mikro-orm": {
    "useTsNode": true,
    "tsConfigPath": "./tsconfig.mikro-orm.json", // and let the compiler know where the file is present.
    "configPaths": [
      "./src/mikro-orm.config.ts",
      "./dist/mikro-orm.config.js"
    ]
}

我希望这能解决问题

Answer 2

我也有同样的问题。安装ts-node包对我有效。

Answer 3

问题在于编译器将代码理解为一个单独的公共脚本文件。您需要将其声明为模块文件。

将此添加到您的package.json顶部

// package.json
{
  "type": "module"
}

正如nodejs文档https://nodejs.org/docs/latest-v13.x/api/esm.html#esm_package_json_type_field中所提到的