使用 mongoose 检查相关 mongodb 集合中是否存在 ID

Question

I have a "Drinkers" model and a "Sodas" model which is "related" - a drinker can have drunk X amount of sodas.

The route to get the data is this

router.get('/all/:drinkerId', sodasController.getAllSodasFromDrinker)

In my sodasController , is there a way to check if :drinkerId exists in the "Drinkers" collection and if not return an error that the drinker doesn't exist, without having to require the drinkersController in the sodasController .

Right now getAllSodasFromDrinker looks like this

const Sodas = require("../models/sodas.model");

exports.getAllSodasFromDrinker = async (req, res, next) => {
  try {
    const id = req.params.drinkerId;

    if (id.match(/^[0-9a-fA-F]{24}$/)) {
      await Sodas.find({ drinker: id }).exec((err, drinkerItem) => {
        if (err) {
          return next(err);
        }

        res.json({ data: drinkerItem });
      });
    } else {
      return next("ID is in the wrong format");
    }
  } catch (error) {
    return next(error);
  }
};

In that function, I want to check if a user exists with the applied ID.

I want to avoid having to const Drinkers = require("../models/drinkers.model") in the sodasController

The Drinkers model:

const Schema = mongoose.Schema;

    const drinkersSchema = new Schema(
      {
        name: {
          type: String,
          required: true,
        },
        email: {
          type: String,
          required: true,
          unique: true,
        },
        sodas: {
          type: Schema.Types.ObjectId,
          ref: "Sodas",
        },
      },
      { timestamps: true }
    );

The Sodas model

const Schema = mongoose.Schema;

    const sodaSchema = new Schema(
      {
        name: {
          type: String,
          required: true,
        },
        drinker: {
          type: Schema.Types.ObjectId,
          ref: "Drinkers",
        },
      },
      { timestamps: true }
    );

Answer 1

I would add a middleware function which validates if the drinkerId exists. If it exists, you can continue to the controller. If not, then you should throw a 404 error.

Your route:

router.get(
    '/all/:drinkerId',
    drinkerMiddleware.exists,
    sodasController.getAllSodasFromDrinker
);

drinkerMiddleware:

exports.exists = async (req, res, next) => {
    try {
        const drinker await Drinker.find({ drinker: req.params.drinkerId }).exec();
        if (!drinker) {
            return next("Drinker not found.");
        }

        return next();
    } catch (error) {
        return next(error);
    }
};