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Yuri Filatov
Yuri Filatov

Posted on • Updated on • Originally published at andersenlab.com

JS object processing functions

Let's look on the example of some database:

We have fields "id", "destination" (where to fly), date of creation, author name, hashtags and flight.

var posts = [
    {
        id: '1',
        destination: 'China',
        createdAt: new Date(2014, -1, 1, 2, 3, 4, 567),
        author: 'ChingHang',
        hashTags:['Berlin'],
        flug: 'A-730'
    },
    {
        id: '2',
        destination: 'Italien',
        createdAt: new Date(2014, -1, 1, 2, 3, 4, 567),
        author: 'PetrovPetr',
        hashTags:['Minsk'],
        flug: 'A-733'
    },
    {
        id: '3',
        destination: 'Spanien',
        createdAt: new Date(2017, 0, 1, 2, 3, 4, 567),
        author: 'IvanovaKatya',
        hashTags:['Moskau'],
        flug: 'A-777'
    },
    {
        id: '4',
        destination: 'Griechenland',
        createdAt: new Date(2013, 0, 1, 2, 3, 4, 567),
        author: 'ZaicevVasiliy',
        hashTags:['Riga'],
        flug: 'A-321'
    },
];
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The code above - our structure of masses to keep information structured.

Then we make a class, where all functions will be initialized and will be connected with our structure.

class arbeit { 
(functions)
constructor(posts) {
    this._posts=posts;
   } 
 } 
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Getting posts with the filter (author)

getPosts(skip=0,top= 10, filterConfig){
        if(filterConfig!=undefined){
            let result = posts.filter(team => team.author === filterConfig.author)
                return result.sort((a, b) => b.createdAt.getTime() - a.createdAt.getTime()).slice(skip,skip+top);
        }
        else {
            return  posts.sort((a, b) => b.createdAt.getTime() - a.createdAt.getTime()).slice(skip,skip+top);
        }
    }
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Getting post with id

 getPost(id) {
        for (var i = 0; i < posts.length; i++) {
            if (posts[i].id === id) {
                return posts[i];
            }
        }
        throw "No object with " + id + " id";
    }
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Validating object

validatePost(Object){
        return Object.id != null && Object.destination != null && Object.destination.length<400
            && Object.author != null && Object.createdAt != null && typeof Object.id === "string" && typeof Object.destination === "string" && typeof Object.flug === "string"
            && typeof Object.author === "string"

    }
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Clearing our "database"

clear(){
        posts.splice(0,posts.length);
    }
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Adding a new post

 addPost(Object){
       if(this.validatePost(Object)){
           posts.splice(posts.length,0,Object);
           return true;
       }
       else {
           return false;
       }
    }
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Editing post

 editPost(id,post){
        if(this.validatePost(post)){
            this.getPost(id).destination=post.destination;
            this.getPost(id).author=post.author;
            return true;
        }else {
            return false;
        }
    }
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Removing post

removePost(id){
        for (var i = 0; i < posts.length; i++) {
            if (posts[i].id === id) {
                return posts.splice(i,1);
            }
        }
        throw "No object with " + id + " id";
    }
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