javascript - 来自另一个文件的模型返回值不适用于 Sequelize.js

Question

我有以下代码目前不起作用。

var config = require('./libs/sequelize-lib.js');
var connection = config.getSequelizeConnection();//Choosing to not pass in variable this time since this should only run via script.
var models = config.setModels(connection);//Creates live references to the models.

//Alter table as needed but do NOT force the change.  If an error occurs we will fix manually.
connection.sync({ alter: true, force: false }).then(function() {
  models.users.create({
    name: 'joe',
    loggedIn: true
  }).then( task => {
    console.log("saved user!!!!!");
  });
  process.exit();//close the nodeJS Script
}).catch(function(error) {
  console.log(error);
});

sequelize-lib.js

var Sequelize = require('sequelize');

exports.getSequelizeConnection = function(stage){
  var argv = require('minimist')(process.argv.slice(2)); //If this file is being used in a script, this will attempt to get information from the argument stage passed if it exists

  //Change connection settings based on stage variable.  Assume localhost by default.
  var dbname = argv['stage'] ? argv['stage']+"_db"                              : 'localdb';
  var dbuser = argv['stage'] ? process.env.RDS_USERNAME                         : 'admin';
  var dbpass = argv['stage'] ? process.env.RDS_PASSWORD                         : 'local123';
  var dbhost = argv['stage'] ? "database-"+argv['stage']+".whatever.com"  : 'localhost';

  //If state variable used during require overide any arguments passed.
  if(stage){
    dbname = stage+"_db";
    dbuser = process.env.RDS_USERNAME
    dbpass = process.env.RDS_PASSWORD
    dbhost = "database-"+stage+".whatever.com"
  }

  var connection = new Sequelize(dbname,dbuser,dbpass, {
    dialect: 'mysql',
    operatorsAliases: false, //This gets rid of a sequelize deprecated warning , refer https://github.com/sequelize/sequelize/issues/8417
    host: dbhost
  });
  return connection;
}

exports.setModels = function(connection){
  //Import all the known models for the project.
  const fs = require('fs');
  const dir = __dirname+'/../models';

  var models = {}; //empty model object for adding model instances in file loop below.

  //@JA - Wait until this function finishes ~ hence readdirSync vs regular readdir which is async
  fs.readdirSync(dir).forEach(file => {
    console.log(file);
    //Split the .js part of the filename
    var arr = file.split(".");
    var name = arr[0].toLowerCase();
    //Create a modle object using the filename as the reference without the .js pointing to a created sequelize instance of the file.
    models[name] = connection.import(__dirname + "/../models/"+file);
  })

  //Showcase the final model.
  console.log(models);

  return models; //This returns a model with reference to the sequelize models
}

但是，使用此设置，我无法使用 create 命令。我的猜测是变量不能以某种方式正确传递。我不确定我做错了什么？

create 命令肯定有效，因为如果在 sequelize-lib.js 中我将 setModels 函数修改为此...

exports.setModels = function(connection){
  //Import all the known models for the project.
  const fs = require('fs');
  const dir = __dirname+'/../models';

  var models = {}; //empty model object for adding model instances in file loop below.

  //@JA - Wait until this function finishes ~ hence readdirSync vs regular readdir which is async
  fs.readdirSync(dir).forEach(file => {
    console.log(file);
    //Split the .js part of the filename
    var arr = file.split(".");
    var name = arr[0].toLowerCase();
    //Create a modle object using the filename as the reference without the .js pointing to a created sequelize instance of the file.
    models[name] = connection.import(__dirname + "/../models/"+file);
    models[name].create({
      "name":"joe",
      "loggedIn":true
    });
  })

  //Showcase the final model.
  console.log(models);

  return models; //This returns a model with reference to the sequelize models
}

然后它起作用了，我看到该项目已添加到数据库中! (引用下面的证明图片)



请注意，此时我只是在变量上运行 create 。 在模型对象没有在文件之间正确传递的情况下，我做错了什么？ 奇怪的部分是我没有在主文件中抛出任何错误？？就好像所有内容都已定义但为空或其他内容，并且该命令永远不会运行并且没有任何内容添加到数据库中。

我也在主文件中尝试过这个，但没有运气。

models["users"].create({
    name: 'joe',
    loggedIn: true
  }).then( task => {
    console.log("saved user!!!!!");
  });

这一切的目的是从模型目录中自动读取模型，并为每个模型创建准备好使用的实例，即使将来添加新的模型也是如此。

更新::

所以我又做了一个有趣的测试，看起来create函数在sync命令的.then()函数中不起作用。看起来它正确地传递了它。把首页改成这样后...

var config = require('./libs/sequelize-lib.js');
var connection = config.getSequelizeConnection();//Choosing to not pass in variable this time since this should only run via script.
var models = config.setModels(connection);//Creates live references to the models using connection previosly created.

models["users"].create({
  "name":"joe",
  "loggedIn":true
});

//Alter table as needed but do NOT force the change.  If an error occurs we will fix manually.
connection.sync({ alter: true, force: false }).then(function() {
  process.exit();//close the nodeJS Script
}).catch(function(error) {
  console.log(error);
});

这样做似乎可以让 create 工作。我不确定这是否是好的形式，因为此时可能没有创建数据库？我需要一种方法让它在同步功能中工作。

Answer 1

好吧，我终于回答了我的问题，但我不确定我喜欢这个答案。

var config = require('./libs/sequelize-lib.js');
var connection = config.getSequelizeConnection();//Choosing to not pass in variable this time since this should only run via script.
var models = config.setModels(connection);//Creates live references to the models using connection previosly created.

//Alter table as needed but do NOT force the change.  If an error occurs we will fix manually.
connection.sync({ alter: false, force: false }).then( () => {
  models["users"].create({
    "name":"joe",
    "loggedIn":true
  }).then( user => {
    console.log("finished, with user.name="+user.name);
    process.exit();
  }).catch( error => {
    console.log("Error Occured");
    console.log(error);
  });
}).catch(function(error) {
  console.log(error);
});

原来 process.exit 是在创建之前触发的，因为创建是异步发生的。这意味着我的所有代码都必须不断地通过回调运行……这似乎有点像一场噩梦。请问有没有更好的办法？