javascript - sequelize.sync({ 强制 : true }) sometimes fails to set up database correctly

Question

我正在尝试使用 Sequelize 和 PostgreSQL 设置测试夹具。然而，我写的测试有时会通过，有时会失败。错误范围从 SequelizeDatabaseError: type "participants_id_seq"already exists 到 SequelizeUniqueConstraintError: Validation error 到 SequelizeDatabaseError: relation "participants"does not exist，这让我相信要么我错误地设置了等待，要么我错误地设置了同步。我试过使用 async/await，我也试过使用回调设置 Promises，但没有成功。

在每次测试之前，我调用sync({ force: true })，就像这样

const { sequelize, participants: Participants } = require('../../models');

const existingUserCredentials = {
  teamName: 'TeamName',
  firstName: 'FirstName',
  lastName: 'LastName',
  email: 'helloworld@helloworld.com',
  password: 'helloworld',
};

const Fixture = async () => {
  try {
    await sequelize.sync({ force: true });
    await Participants.create(existingUserCredentials);
  } catch (err) {
    logger.error(err);
    throw err;
  }
};

module.exports = {
  Fixture
};

然后我在我的测试用例中这样调用它:

describe('POST /login', () => {
  beforeEach(async () => {
    await Fixture();
  });

  it('throws unauthorized when user does not exist', async () => {
    const { body, status } = await request(app)
      .post('/api/login')
      .send({
        email: 'someemail@helloworld.com',
        password: 'hunter123',
      });

    expect(body).toEqual({
      message: messages.INVALID_LOGIN_CREDENTIALS,
    });
    expect(status).toEqual(HttpStatus.UNAUTHORIZED);
  });
});

此测试有时会通过，但有时会失败并出现不同的错误。

我的模型是这样的:

const bcrypt = require('bcryptjs');

module.exports = (sequelize, DataTypes) => {
  const Participant = sequelize.define('participants', {
    teamName: {
      type: DataTypes.STRING,
      allowNull: true,
    },
    firstName: {
      type: DataTypes.STRING,
      allowNull: false,
    },
    lastName: {
      type: DataTypes.STRING,
      allowNull: false,
    },
    email: {
      type: DataTypes.STRING,
      allowNull: false,
    },
    password: {
      type: DataTypes.STRING,
      allowNull: false,
      set(password) {
        const hash = bcrypt.hashSync(password, bcrypt.genSaltSync(10));
        this.setDataValue('password', hash);
      },
    },
  });

  Participant.verifyPassword = (password, hash) =>
    bcrypt.compareSync(password, hash);

  return Participant;
};

我的迁移看起来像这样

module.exports = {
  up: (queryInterface, Sequelize) =>
    queryInterface.createTable('participants', {
      id: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: Sequelize.INTEGER,
      },
      teamName: {
        type: Sequelize.STRING,
        allowNull: true,
      },
      firstName: {
        type: Sequelize.STRING,
        allowNull: false,
      },
      lastName: {
        type: Sequelize.STRING,
        allowNull: false,
      },
      email: {
        type: Sequelize.STRING,
        allowNull: false,
      },
      password: {
        type: Sequelize.STRING,
        allowNull: false,
      },
      createdAt: {
        allowNull: false,
        type: 'TIMESTAMP',
        defaultValue: Sequelize.literal('CURRENT_TIMESTAMP'),
      },
      updatedAt: {
        allowNull: false,
        type: 'TIMESTAMP',
        defaultValue: Sequelize.literal('CURRENT_TIMESTAMP'),
      },
    }),
  down: (queryInterface) => queryInterface.dropTable('participants'),
};

我是否正确设置了它以便我可以为每个测试提供一个干净的数据库？感谢您的帮助!

Answer 1

更新

我想通了。原来 Jest 并行运行测试用例，所以测试数据库被多个测试用例同时使用。真正的解决方案是通过将 --runInBand 标志添加到测试命令来顺序运行测试用例

// package.json
{
    ...
    "scripts": {
        ...
        "test": "cross-env NODE_ENV=test jest --runInBand"
    }
    ...
}

但是，这会减慢运行测试用例所需的时间。更好的解决方案可能是模拟您的数据库，而不是使用实际的测试数据库。那里有一些，例如 sequelize-mock和 sequelize-mocking .

---

所以，我无法用 PostgreSQL 解决这个问题。相反，我将我的 Sequelize 配置切换为使用 SQLite 进行测试并且它有效。这是我的配置

module.exports = {
  development: {
    username: process.env.PGUSER,
    password: process.env.PGPASSWORD,
    database: process.env.PGDATABASE,
    host: process.env.PGHOST || '127.0.0.1',
    dialect: 'postgres',
    operatorsAliases: false,
  },
  test: {
    username: process.env.SQLITEUSER,
    password: process.env.SQLITEPASSWORD,
    database: process.env.SQLITEDATABASE,
    host: process.env.PGHOST || '127.0.0.1',
    dialect: 'sqlite',
    operatorsAliases: false,
  },
  production: {
    username: process.env.PGUSER,
    password: process.env.PGPASSWORD,
    database: process.env.PGPRODDATABASE,
    host: process.env.PGHOST || '127.0.0.1',
    dialect: 'postgres',
    operatorsAliases: false,
    logging: false,
  },
};

虽然我不认为这是一个很好的解决方案，但我打算让这个问题悬而未决