如何使用 Typeorm 创建与 Postgres 的连接

Posted 2023-03-08

【中文标题】如何使用 Typeorm 创建与 Postgres 的连接

【英文标题】：How can I create a Connection to Postgres using Typeorm

【发布时间】：2020-08-30 04:50:37

【问题描述】：

我正在关注 Ben Awad 于 1/2019 年发布的名为 TypeGraphQL 的 YouTube 视频系列。第一个视频建立了开发环境，第二个视频介绍了 Typeorm 和 PostgreSQL。在视频的这一点上，事情很简单。该代码定义了一个实体并创建了一个连接，该连接应导致代码在启动时创建表。 我在启动时收到此错误：

[nodemon] to restart at any time, enter `rs`
[nodemon] watching path(s): *.*
[nodemon] watching extensions: ts,json
[nodemon] starting `ts-node src/index.ts`

/Users/jboss/projects/ts-graphql/src/index.ts:141
export EntityManager from "./entity-manager/EntityManager";
        ^
TypeError: Cannot set property EntityManager of #<Object> which has only a getter
    at Object.<anonymous> (/Users/jboss/projects/ts-graphql/src/index.ts:141:9)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1103:10)
    at Module.load (internal/modules/cjs/loader.js:914:32)
    at Function.Module._load (internal/modules/cjs/loader.js:822:14)
    at Module.require (internal/modules/cjs/loader.js:956:19)
    at require (internal/modules/cjs/helpers.js:74:18)
    at Object.<anonymous> (/Users/jboss/projects/ts-graphql/src/index.ts:5:1)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Module.m._compile (/Users/jboss/projects/ts-graphql/node_modules/ts-node/src/index.ts:858:23)
[nodemon] app crashed - waiting for file changes before starting...

这里是 tsconfig.json

  "compilerOptions": 
    "target": "es6",
    "module": "commonjs",
    "lib": ["dom", "es6", "es2017", "esnext.asynciterable"],
    "sourceMap": true,
    "outDir": "./dist",
    "moduleResolution": "node",
    "declaration": false,

    "composite": false,
    "removeComments": true,
    "noImplicitAny": true,
    "strictNullChecks": true,
    "strictFunctionTypes": true,
    "noImplicitThis": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noImplicitReturns": true,
    "noFallthroughCasesInSwitch": true,
    "allowSyntheticDefaultImports": false,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "skipLibCheck": true,
    "baseUrl": ".",
    "rootDir": "src"
  ,
  "exclude": ["node_modules"],
  "include": ["./src/**/*.tsx", "./src/**/*.ts"]

这里是 package.json：

  "name": "ts-graphql",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": 
    "apollo-server-express": "^2.13.1",
    "bcryptjs": "^2.4.3",
    "express": "^4.17.1",
    "graphql": "^15.0.0",
    "pg": "^8.1.0",
    "reflect-metadata": "^0.1.13",
    "type-graphql": "^1.0.0-rc.1",
    "typeorm": "^0.2.24"
  ,
  "devDependencies": 
    "@types/bcryptjs": "^2.4.2",
    "@types/express": "^4.17.6",
    "@types/graphql": "^14.5.0",
    "@types/node": "^14.0.1",
    "nodemon": "^2.0.3",
    "ts-node": "^8.10.1",
    "typescript": "^3.9.2"
  ,
  "scripts": 
    "start": "nodemon --exec ts-node src/index.ts"
  

这里是 ormconfig.json:

  "name": "default",
  "type": "postgres",
  "host": "localhost",
  "port": 5432,
  "username": "postgres",
  "password": "docker",
  "database": "typegraphql",
  "synchronize": true,
  "logging": true,
  "entities": [ 
    "src/entity/**/*.*"
  ]

还有 index.ts：

import  ApolloServer  from "apollo-server-express";
import * as Express from "express";
import  buildSchema, Resolver, Query  from 'type-graphql';
import  createConnection  from "typeorm";

@Resolver()
class HelloResolver 

  @Query(() => String, name: 'helloWorld')
  async hello() 
    return "Hi from Typescript GraphQL!";
  


let main = async () => 
  await createConnection();

  const schema = await buildSchema(
    resolvers: [HelloResolver]
  );

  const apolloServer = new ApolloServer( schema )

  const app = Express();
  apolloServer.applyMiddleware( app );
  app.listen(4000, () => 
    console.log('Server started on http://localhost:4000');
  );


main();

最后是 User.ts：

import Entity, PrimaryGeneratedColumn, Column, BaseEntity from "typeorm";

@Entity(  schema: "public" )
export class User extends BaseEntity 

    @PrimaryGeneratedColumn()
    id: number;

    @Column()
    firstName: string;

    @Column()
    lastName: string;

    @Column("text",  unique: true)
    email: string;

    @Column()
    password: string;

谁能告诉我如何让它工作？我不认为我理解这个问题。

【参考方案1】：

这是昨天在 Typeorm 项目中报告的一个错误。我花了一天时间才找到它。在他们的 Slack 中找到它。爱松弛。 https://github.com/typeorm/typeorm/issues/6054 我的解决方案是：

npm install tslib@1.11.2

然后将以下内容添加到 package.json 中：

  "resolutions": 
    "ts.lib": "1.11.2"
  ,

然后用yarn重新开始。

似乎 tslib 1.12 引起了一些问题。