如何从函数中的多个Schema中检索和传递数据

im newbie in expressjs and wondering how to retrieve and pass data from more than 1 schema in my controller.

我在expressjs中的新手,并想知道如何从我的控制器中的多个架构中检索和传递数据。

here is the case, pretend i wanna open add_new_blog page and below is the router;

在这种情况下,假装我想打开add_new_blog页面,下面是路由器;

router.get('/add_new_blog', BlogController.index);

well then in BlogController.index i need to retrieve Category and Tag Models.

那么在BlogController.index中我需要检索类别和标签模型。

const Category = require('models/categorySchema');
const Tag = require('models/tagSchema');

module.exports = {

  index(req, res, next){

    Category.find({});
    Tag.find({});

    // how to find/retrieve data from both Schema then i pass them to Views.


    res.render('/blog/blogForm');
  }
}

The Question is What the coding will look like to retrieve the data from both then pass it to the view?

问题是从两者检索数据然后将其传递给视图的编码是什么样的?

1 个解决方案

#1

You can use Promise.all(), get the two mongoose calls data and then render it.

你可以使用Promise.all(),获取两个mongoose调用数据,然后渲染它。

const categoryFind = Category.find({}).exec(); // exec() returns a Promise.
const tagsFind = Tags.find({}).exec();

Promise.all(categoryFind, tagsFind).then((values) => {
  res.render('/blog/blogForm', { categories: values[0], tags: values[1] });
});

Notice that I render inside the callback, that is because mongoose calls are asynchronous. Otherwise you will be rendering before the queries have completed.

请注意,我在回调内部渲染,这是因为mongoose调用是异步的。否则,您将在查询完成之前进行渲染。

That is the same as:

这与以下相同:

Category.find({}, (err, catData) => {
  Tags.find({}, (err, tagsData) => {
    res.render('/blog/blogForm', { categories: catsData, tags: tagsData });
  }
}

#1