How to do soft delete with mongodb using nodejs - node.js

Question

I'm able to delete data from the view , but at the sametime its getting deleted from mongodb which shouldn't happen.
I tried mongoose-soft-delete plugin to perform soft delete, but it isn't working
//schema
var mongoose= require('mongoose');
let softDelete = require('mongoosejs-soft-delete');
var Schema=mongoose.Schema;
var newblogSchema=new Schema({
user_id:Number,
title:String,
description:String,
summary:String,
hashtag:String
})
var newblogs=mongoose.model('NewBlog',newblogSchema);
newblogSchema.plugin(softDelete);
module.exports=newblogs;
//html template
<table>
<tr>
<th>Title</th>
<th>Description</th>
<th>Summary</th>
<th>HashTags</th>
</tr>
<tr *ngFor="let blog of blogs;">
<td >{{blog.title}}</td>
<td [innerHtml]="blog.description| safeHtml">{{blog.description}}</td>
<td>{{blog.summary}}</td>
<td>{{blog.hashtag}}</td>
<td> <a routerLink="/blog"><button type="button"
(click)="editblog(blog._id,blog.title,blog.description,blog.summary,blog.hashtag)">
Edit</button></a>
<td><button type="button" (click)="deleteblog(blog._id)">Delete</button>
</tr>
</table>
//ts file
deleteblog(blogid) {
var result = confirm('Want to delete?');
if (result === true) {
this.blogservice.deleteblog(blogid).subscribe(response => {this.blogs = response; });
}
//service
deleteblog(blogid):Observable<any>{
return Observable.create(observer=>{
this.http.post('http://localhost:4000/api/deleteblog', {_id: blogid}, {headers: new HttpHeaders({'Content-Type':'application/json'})}
)
.subscribe((response:Response)=>{
observer.next(response);
observer.complete();
});
});
}
//api.js
router.post('/deleteblog',(req,res)=>{
var body=req.body;
newblog.findByIdAndRemove({_id:body._id},(error,newblog)=>{if(error){
console.log(error);
}
else{
return res.json({message:'deleted',data:newblog});
}
});
});
Now the data is getting deleted from view as well as mongodb.
Expected result is to delete data only from the view and not from mongodb

Answer 1

we can implement soft delete with plugin, middleware and $isDeleted document method
soft delete plugin code:
import mongoose from 'mongoose';
export type TWithSoftDeleted = {
isDeleted: boolean;
deletedAt: Date | null;
}
type TDocument = TWithSoftDeleted & mongoose.Document;
const softDeletePlugin = (schema: mongoose.Schema) => {
schema.add({
isDeleted: {
type: Boolean,
required: true,
default: false,
},
deletedAt: {
type: Date,
default: null,
},
});
const typesFindQueryMiddleware = [
'count',
'find',
'findOne',
'findOneAndDelete',
'findOneAndRemove',
'findOneAndUpdate',
'update',
'updateOne',
'updateMany',
];
const setDocumentIsDeleted = async (doc: TDocument) => {
doc.isDeleted = true;
doc.deletedAt = new Date();
doc.$isDeleted(true);
await doc.save();
};
const excludeInFindQueriesIsDeleted = async function (
this: mongoose.Query<TDocument>,
next: mongoose.HookNextFunction
) {
this.where({ isDeleted: false });
next();
};
const excludeInDeletedInAggregateMiddleware = async function (
this: mongoose.Aggregate<any>,
next: mongoose.HookNextFunction
) {
this.pipeline().unshift({ $match: { isDeleted: false } });
next();
};
schema.pre('remove', async function (
this: TDocument,
next: mongoose.HookNextFunction
) {
await setDocumentIsDeleted(this);
next();
});
typesFindQueryMiddleware.forEach((type) => {
schema.pre(type, excludeInFindQueriesIsDeleted);
});
schema.pre('aggregate', excludeInDeletedInAggregateMiddleware);
};
export {
softDeletePlugin,
};
you can use as global for all schemas
mongoose.plugin(softDeletePlugin);
or for concrete schema

Answer 2

For Soft delete, you should maintain an active flag column that should only contain values as 0 and 1.
This way, you could analyse whether a record is deleted or not.
While displaying, add another clause for displaying only the records that have flag value 1. And while deleting, just update that flag's value to 0.
This would do the job.
For Example, here user 2 is deleted. with activeFlag as 0.
ID memberID userStatus groupCode activeFlag
1 user1 1 4455 1
2 user2 1 4220 0
3 user3 2 4220 1

Answer 3

Try to use https://www.npmjs.com/package/soft-delete-mongoose-plugin
A simple and friendly soft delete plugin for mongoose.