SEQUELIZE：belongsTo 调用的东西不是 Sequelize.Model 的子类答案

【问题标题】：SEQUELIZE: belongsTo called with something that's not a subclass of Sequelize.ModelSEQUELIZE：belongsTo 调用的东西不是 Sequelize.Model 的子类
【发布时间】：2020-09-21 23:42:50
【问题描述】：

我是 sequelize 的新手，我正在尝试创建两个表。用户和项目。我为每个名为 UserModel 和 ProjectModel 的模型定义了一个模型，当我尝试将项目与用户关联时，我遇到了这个错误：

belongsTo 调用的东西不是 Sequelize.Model

这些是我定义每个模型的文件：

user.js

module.exports = (sequelize, DataType) => {
    const UserModel = sequelize.define("user", {
        id: {
            type: DataType.INTEGER,
            primaryKey: true,
            autoIncrement: true,
            allowNull: false,
        },
        email: {
            type: DataType.STRING,
            allowNull: false,
            isEmail: {
                msg: "The format of the e-mail is not correct"
            },
            validate: {
                notNull: {
                    msg: "E-mail cannot be empty"
                }
            }
        },
        name: {
            type: DataType.STRING,
            is: /^[a-zA-Z ]+$/i,
            allowNull: false,
            validate: {
                notNull: {
                    msg: "Name cannot be empty"
                }
            }
        },
        surname: {
            type: DataType.STRING,
            is: /^[a-zA-Z ]+$/i,
            allowNull: false,
            validate: {
                notNull: {
                    msg: "Surname cannot be empty"
                }
            }
        }
    });
    UserModel.associate = (models) => {
        UserModel.hasMany(models.ProjectModel, {
            foreignKey: "userID"
        })
    }

    return UserModel;    
};

project.js

module.exports = (sequelize, DataType) => {
    const ProjectModel =  sequelize.define("project", {
        id: {
            type: DataType.INTEGER,
            primaryKey: true,
            autoIncrement: true,
            allowNull: false,
        },
        name: {
            type: DataType.STRING,
            is: /^[a-zA-Z ]+$/i,
            allowNull: false,
            validate: {
                notNull: {
                    msg: "Name cannot be empty"
                }
            }
        },
        body: {
            type: DataType.TEXT,
            allowNull: false,
            validate: {
                notNull: {
                    msg: "Body cannot be empty"
                }
            }
        },
        status: {
            type: DataType.ENUM("active", "inactive", "declined", "completed"),
            allowNull: false,
            validate: {
                notNull: {
                    msg: "Status cannot be empty"
                }
            }
        },
        userID: {
            type: DataType.INTEGER,
            allowNull: false,
            validate: {
                notNull: {
                    msg: "userID cannot be empty"
                }
            },
            references: {
                model: UserModel,
                key: "id"
            }            
        }
    }); 
    ProjectModel.associate = (models) => {
        ProjectModel.belongsTo(models.UserModel, {
            foreignKey: "userID"
        });
    }

    ProjectModel.belongsTo(UserModel, {
        foreignKey: "userID"
    });


    return ProjectModel;
}

我做错了什么？

【问题讨论】：

标签： node.js sequelize.js

【解决方案1】：

最后，我找到了解决问题的方法。在这个关联中，例如：

ProjectModel.associate = (models) => {
    ProjectModel.belongsTo(models.UserModel, {
        foreignKey: "userID"
    });
}

使用变量 models.UserModel 我引用了模型返回的变量。取而代之的是，您必须写下表的名称。所以，就我而言，正确的功能是：

ProjectModel.associate = (models) => {
    ProjectModel.belongsTo(**models.users**, {
        foreignKey: "userID"
    });
}

【讨论】：