如何在 beforeAll() 中调用 DB 连接并在 afterAll() 中关闭 DB 连接

Question

我是 Jest 和 TypeORM 的新手，想使用 typeorm 和 Jest 开发数据库验证框架。如何在 beforeAll() 中调用三个数据库连接实例。

这是一个使用 TypeORM 和 Jest 进行数据库验证的新框架，Ormconfig.json 包含三个数据库的详细信息，并有一个用于数据库连接的 .ts 类和一个测试类。

ormconfig.json

[{
  "name": "default",
  "type": "mysql",
  "host": "127.0.01",
  "port": 3306,
  "username": "sdf",
  "password": "uuehfldjskh",
  "database": "ifsdjh",
  "synchronize": true,
  "logging": false,
  "entities": [
    "src/entity/**/*.ts"
  ],
  "migrations": [
    "src/migration/**/*.ts"
  ],
  "subscribers": [
    "src/subscriber/**/*.ts"
  ],
  "cli": {
    "entitiesDir": "src/entity",
    "migrationsDir": "src/migration",
    "subscribersDir": "src/subscriber"
  }
},
  {
    "name": "hello",
    "type": "mysql",
    "host": "127.0.01",
    "port": 3306,
    "username": "weqwe",
    "password": "das",
    "database": "dsfds",
    "synchronize": true,
    "logging": false,
    "entities": [
      "src/entity/**/*.ts"
    ],
    "migrations": [
      "src/migration/**/*.ts"
    ],
    "subscribers": [
      "src/subscriber/**/*.ts"
    ],
    "cli": {
      "entitiesDir": "src/entity",
      "migrationsDir": "src/migration",
      "subscribersDir": "src/subscriber"
    }
  }
]

创建连接.ts

import {createConnection, getConnectionOptions} from "typeorm";

export const createConnection = async  () => {
    const createConnectionOptions = await getConnectionOptions(process.env.NODE_ENV);
    return createConnection({...createConnectionOptions,name:"default"});
}

测试类.ts

import {Patches} from "../entity/Patches";
import {createConnection} from "../utils/createConnection";

test('Query with getRepository()', async () => {
    jest.setTimeout(100000);
    const connection = await createConnection();
    const Count = await connection.getRepository(User).count();
    console.log(Count);
    expect(Count).toEqual(32);
    await connection.close();
})

如何在每次测试之前移动到数据库的连接 -

beforeAll(){
connectionDB();
}

test()
{
   connection(db1) //connect to DB1
   /** Do operation on DB1 **/
   connection(db2) //connect to DB2
   /** Do operation on DB2 **/
   Compare both result of DB1 and DB2
}

afterAll()
{
connectionDB().close();
}

Answer 1

伪代码：

let connection;

beforeAll(){
  connection = connectionDB();
}

test() {
  //...
}

afterAll() {
  connection.close();
}