How to set relation foreign key to be required

问题

I have two models. Company and Booking.
In the relation part of model Company

"bookings": {
  "type": "hasMany",
  "model": "Booking",
  "foreignKey": "companyId"
}

The issue is, it is possible to post a Booking without companyId which is not ok.
From the explorer.

Booking {
  bookingId (string, optional),
  name (string),
  location (string),
  companyId (string, optional)
}

回答1:

You actually can't enforce this particular validation out-of-the-box. Instead you have a couple different options:

a) You can enforce the creation of Booking through company through the endpoint, POST /api/Company/{id}/Bookings by disabling Booking.disableRemoteMethod('create', ...) along with any other methods that have the ability to create records from the Booking model.

b) You can add a remote hook to check whether or not the company record exists and throw an error accordingly.

Booking.beforeRemote('create', function(ctx, booking, next) {
  var Company = Booking.app.models.Company;
  var companyId = ctx.req.body.companyId;

  if (companyId) {
    errorMsg = 'Company with id=' + companyId + ' does not exist.';
    var noCompany = new Error(errorMsg);
    Company.findById(companyId, function(err, company) {
      if (err) next(err);
      if (!company) {
        ctx.res.statusCode = 400;
        next(noCompany);
      } else {
        next();
      }
    });
  } else {
    next();
  }
});

You will also have to do the same thing for any other endpoints that allow record create such as PUT /api/Bookings.

Hope that helps!

回答2:

You can add the companyId property explicitly in the booking.json file, and add the required:true property. It would look like

{
    "properties": {
        "companyId": {
            "type": "number",
            "required": true
        },
        ... //other properties
    }
}

回答3:

In richardpringle's answer part b booking was an empty object for me.

I was able to get this answer to work by adding app to the booking.js file like below:

'use strict';
var app = require('../../server/server');

module.exports = function(Booking) {
  Booking.beforeRemote('create', function(ctx, booking, next) {
    var Company = app.models.Company;
    var companyId = ctx.req.body.companyId;

    if (companyId) {
      errorMsg = 'Company with id=' + companyId + ' does not exist.';
      var noCompany = new Error(errorMsg);
      Company.findById(companyId, function(err, company) {
        if (err) next(err);
        if (!company) {
          ctx.res.statusCode = 400;
          next(noCompany);
        } else {
          next();
        }
      });
    } else {
      next();
    }
  });
};

line 2 is new
line 6 is modified from richardpringle's answer
- From: var Company = Booking.app.models.Company;
- To: var Company = app.models.Company;

来源：https://stackoverflow.com/questions/39080231/how-to-set-relation-foreign-key-to-be-required

标签

loopbackjs