How to add id of an object in another object with AngularJS

Question

I have two objects, Events & Comments:

   {
    "name": "events",
    "fields": {
      "name": {
        "type": "string"
      },
      "date": {
        "type": "datetime"
      },
      "time": {
        "type": "datetime"
      },
      "info": {
        "type": "text"
      },
      "users": {
        "collection": "users_events",
        "via": "event"
      },
      "eventCommentsId": {
        "collection": "comments",
        "via": "eventId"
      },
    }
  },
  {
    "name": "comments",
    "fields": {
      "content": {
        "type": "text"
      },
      "owner": {
        "object": "users"
      },
      "eventId": {
        "object": "events"
      },
      "date": {
        "type": "datetime"
      }
    }
  }

Each event should have its own unique collection of comments. So, its a One to Many relationship.

Right now, I can just get all of the comments instead of only the ones that correspond to each event. My thinking is that I need to include the id of the event in each comment. But, I'm not entirely sure how to do that.

If anyone could help me out with this, that would be amazing!

I'm building the app with Ionic/AngularJS and I'm storing my data with Backand.

Thanks in advance!

.controller('EventDetailCtrl', ['$scope', '$stateParams', '$ionicSideMenuDelegate', 'EventService', 'CommentService',function($scope, $stateParams, $ionicSideMenuDelegate, EventService, CommentService) { 
  $scope.openMenu = function () {
    $ionicSideMenuDelegate.toggleLeft();
  };    

  var id = $stateParams.id;
  EventService.getEvent(id).then(function(response){
   $scope.event = response.data;
});

  $scope.comments = [];
  $scope.input = {};

  function getAllComments() {
    CommentService.getComments()
    .then(function (result) {
      $scope.comments = result.data.data;
    });
  }

  $scope.addComment = function() {
    CommentService.addComment($scope.input)
    .then(function(result) {
      $scope.input = {};
      getAllComments();
    });
  }

  $scope.deleteComment = function(id) {
    CommentService.deleteComment(id)
    .then(function (result) {
      getAllComments();
    });
  }

  getAllComments();

}])

.service('CommentService', function ($http, Backand) {    
  var baseUrl = '/1/objects/';
  var objectName = 'comments/';

  function getUrl() {
    return Backand.getApiUrl() + baseUrl + objectName;
  }

  function getUrlForId(id) {
    return getUrl() + id;
  }

  getComments = function () {
    return $http.get(getUrl());
  };

  addComment = function(event) {
    return $http.post(getUrl(), event);
  }

  deleteComment = function (id) {
    return $http.delete(getUrlForId(id));
  };

  getComment = function (id) {
    return $http.get(getUrlForId(id));
  };


  return {
    getComments: getComments,
    addComment: addComment,
    deleteComment: deleteComment,
    getComment: getComment
  }   
})

Answer 1

It is better to move the logic of getting all comments of a specific event from the backend rather than getting everything from server and filtering on front-end. You can make the call such as:

http://mysite/getComments?eventId=2533213

And in your comments schema (for DB), you can have one field as eventId. You can then fetch all the comments having the event Id provided in the call from DB and return to your app in response.

In front-end you can do :

Controller:

function getCommentsById(event) {
    CommentService.getCommentsById(event)
    .then(function (result) {
      $scope.comments = result.data.data;
    });
  }

Service:

getCommentsById = function (event) {
    return $http.get(getUrl() + "?eventId=" + event.id); //supposing you have event.id
  };