如何使用 NodeJS 为 Sequelize model 添加默认值？

Question

我已经创建了一个 controller 来将新值添加到数据库中，但现在我不知道如何将默认值设置为 Sequelize。 让我在下面演示我的代码

Model 用户：

module.exports = (sequelize, Sequelize) => {
  const User = sequelize.define("user", {
    user_id: {
      type: Sequelize.STRING,
      autoIncrement: true,
      primaryKey: true,
    },
    username: {
      type: Sequelize.STRING,
    },
    password: {
      type: Sequelize.STRING,
    },
    full_name: {
      type: Sequelize.STRING,
    },
    email: {
      type: Sequelize.STRING,
    },
    role_id: {
      type: Sequelize.STRING,
    },
    is_active: {
      type: Sequelize.BOOLEAN,
    },
    created_date: {
      type: Sequelize.DATE,
    },
    created_by: {
      type: Sequelize.STRING,
    },
    updated_date: {
      type: Sequelize.DATE,
    },
    updated_by: {
      type: Sequelize.STRING,
    },
  });

  return User;
};

Model 作用：

module.exports = (sequelize, Sequelize) => {
  const Role = sequelize.define("role", {
    role_id: {
      type: Sequelize.STRING,
      autoIncrement: true,
      primaryKey: true,
    },
    role_name: {
      type: Sequelize.STRING,
    },
    is_active: {
      type: Sequelize.BOOLEAN,
    },
    created_date: {
      type: Sequelize.DATE,
    },
    created_by: {
      type: Sequelize.STRING,
    },
    updated_date: {
      type: Sequelize.DATE,
    },
    updated_by: {
      type: Sequelize.STRING,
    },
  });

  return Role;
};

Controller 用户：

const db = require("../models");
const User = db.users;

exports.create = (req, res) => {
    // Validate request
    if (!req.body.username) {
      res.status(400).send({
        message: "Content can not be empty!"
      });
      return;
    }
  
    // Create a Tutorial
    const user = {
        username: req.body.username,
        password: req.body.password,
        full_name: req.body.full_name,
        email: req.body.email,
        role_id: req.body.role_id,
        is_active: req.body.is_active,
        created_date: req.body.created_date,
        created_by: req.body.created_by,
        updated_date: req.body.updated_date,
        updated_by: req.body.updated_by,
    };
  
    // Save Tutorial in the database
    User.create(user)
      .then(data => {
        res.send(data);
      })
      .catch(err => {
        res.status(500).send({
          message:
            err.message || "Some error occurred while creating new User."
        });
      });
  };

现在我需要帮助添加默认值，即每个值必须是角色是 USER 和is_active = 1 。 如果您有任何想法，请帮助我或给我一些建议，以便我可以更轻松地完成此问题。 而且，我希望你能支持这篇文章。 谢谢

Answer 1

您可以在迁移文件中的数据库级别定义默认值。 或者，您也可以在 model 定义本身中定义续集级别。

module.exports = (sequelize, Sequelize) => {
  const User = sequelize.define("user", {
    user_id: {
      type: Sequelize.STRING,
      autoIncrement: true,
      primaryKey: true,
    },
role_name: {
      type: Sequelize.STRING,
      defaultValue: 'USER'
    },
    is_active: {
      type: Sequelize.BOOLEAN,
      defaultValue: 1
    }
    });

  return User;
};

https://sequelize.org/docs/v6/core-concepts/model-basics/#default-values