I have successfully set up a database using mongodb, and I have managed to add new entries to my collection. However, when I use a similar method to delete, nothing happens.
Express.js code
router.post('/deleteproject', function(req, res) {
var MongoClient = mongodb.MongoClient;
var url = 'mongodb://localhost:27017/plugd';
MongoClient.connect(url, function(err, db) {
if (err) {
console.log("Unable to connect to server", err);
} else {
console.log('Connected to server');
var collection = db.collection('projects');
collection.remove(
{_id: new mongodb.ObjectID(req.body)}, function(err, result) {
if (err) {
console.log(err);
} else {
res.redirect("thelist");
}
db.close();
});
}
});
});
Jade code
h2.
ul
Projects
each project, i in projectlist
#project_list_item
a(href='#') #{project.owner} - #{project.project}
p #{project.ref1}
p #{project.ref2}
p #{project.ref3}
form#form_delete_project(name="deleteproject", method="post", action="/deleteproject")
input#input_name(type="hidden", placeholder="", name="_id", value="#{project._id}")
button#submit_project(type="submit") delete
I figured it out. Here is my fix for deleting data from a mongodb collection using a router in express.js.
Express.js
router.post('/deleteproject', function(req, res) {
var MongoClient = mongodb.MongoClient;
var ObjectId = require('mongodb').ObjectId;
var url = 'mongodb://localhost:27017/app';
MongoClient.connect(url, function(err, db) {
if (err){
console.log('Unable to connect to server', err);
} else {
console.log("Connection Established");
var collection = db.collection('projects');
collection.remove({_id: new ObjectId(req.body._id)}, function(err, result) {
if (err) {
console.log(err);
} else {
res.redirect("thelist");
}
db.close();
});
}
});
});
Jade code
extends layout
block content
h2.
Projects
ul
each project, i in projectlist
#project_list_item
a(href='#') #{project.owner} - #{project.project}
p #{project.ref1}
p #{project.ref2}
p #{project.ref3}
form#form_delete_project(name="deleteproject", method="post", action="/deleteproject")
input#input_name(type="hidden", placeholder="", name="_id", value="#{project._id}")
button#submit_project(type="submit") delete
The jade file is rendering to a page called 'thelist' that lists each item in the collection.
The form section handles the delete function for each item in the list.
This works for me as long as I keep Jade's indents happy :)
Try this and see if it works :
router.post('/deleteproject', function(req, res) {
var MongoClient = mongodb.MongoClient;
var url = 'mongodb://localhost:27017/plugd';
MongoClient.connect(url, function(err, db) {
if (err) {
console.log("Unable to connect to server", err);
} else {
console.log('Connected to server');
var collection = db.collection('projects');
collection.remove(
{_id: req.body}, function(err, result) {
if (err) {
console.log(err);
} else {
res.redirect("thelist");
}
db.close();
});
}
});
});
Since you're on MongoDB's Node.js Native Driver, you don't need to marshall _id inside ObjectId. You can directly specify the _id as string
Related
Im having trouble figuring out how to query the price. My current attempt is not working and im not sure what you have to type in the local host.
http://localhost:3000/priceSearch?
I have implemented - orderSearch.find({price:{$gt:400, $lt: 700}})
the price field in my mongodb is a number not a a string
Thank you:D
Here is my code:
priceSearch.ejs
var express = require('express');
var router = express.Router();
var mongodb = require('mongodb');
var MongoClient = mongodb.MongoClient;
var url = 'mongodb://localhost:27017/WishList';
router.get('/', function (req, res) {
var price = req.query.price;
MongoClient.connect(url, function (err, db) {
if (err) {
console.log("Unable to connect to the server", err);
} else {
console.log("Connection established...");
var orderSearch = db.collection('orders');
// find document who satisify price
orderSearch.find({price:{$gt:400, $lt: 700}}).toArray(function (err, result) {
if (err) {
res.send(err);
} else if (result.length) {
res.render('priceSearch',
{
priceSearch: result,
title: 'Product price search',
}
);
} else {
res.send("No documents found");
}
db.close();
});
}
});
});
module.exports = router;
req.query.price;
i added a stupid var to it
Hello I'm learning mongoDB and trying to print out my database query results to the browser.
I have a program working where it writes the output JSON to the console using console.log()
Is there a way to use res.send() (using express) or response.write() and response.send() to simply output the raw JSON data that the database query gets?
In other words, How can I make my database invokatation return a string?
// Use connect method to connect to the server
var invokeDatabase = function() {
MongoClient.connect(url, function(err, db) {
assert.equal(null, err);
console.log("Connected successfully to database server");
findDocuments(db, function() {
findDocumentsFiltered(db, function() {
db.close();
});
});
});
};
//routes
app.get('/', function(req, res) {
console.log("Someone connected.")
res.send("accessing database... " + invokeDatabase())
//res.send('Welcome G')
})
This example may help you to understand
// Use connect method to connect to the server
var invokeDatabase = function(callback) {
MongoClient.connect(url, function(err, db) {
//assert.equal(null, err);
if(err) {
console.log("Unable to connect database");
callback(err, null);
return;
}
console.log("Connected successfully to database server");
findDocuments(db, function() {
findDocumentsFiltered(db, function(err, data) {
callback(err, data);
db.close();
});
});
});
};
//Added for demo. Here users is collection
var findDocumentsFiltered = function(db, callback) {
db.collection('users').find({}).toArray(function(err, userList) {
callback(err, userList);
});
};
//routes
app.get('/', function(req, res) {
console.log("Someone connected.")
invokeDatabase(function(err, data) {
if(err)
res.status(500).json({error: err});
else
res.json(data);
}))
//res.send('Welcome G')
})
How to find mongo data(db.collection_name.find()) through express route and print the data into jade template.
Here is my express route( I am using express2.5.8)
app.get('/showData',function(req,res){
db.collection('comments',function(err, data){
if(err){
throw err;
}
else{
data.find();
res.render('help', {data: data});
}
});
});
It through an error that db.collection is not a function
For a quick start, you can connect to the db first, and then store db in a variable:
var MongoClient = require('mongodb').MongoClient;
var database;
// Connection URL
var url = 'mongodb://localhost:27017/myproject';
// Use connect method to connect to the Server
MongoClient.connect(url, function(err, db) {
if (!err) {
console.log("Connected correctly to server");
database = db;
}
})
app.get('/showData',function(req,res){
database.collection('comments',function(err, data){
if(err){
throw err;
}
else {
data.find();
res.render('help', {data: data});
}
});
Later you can move all the db connectivity functionality into separate file and just require it when needed.
I find the answer myself below is the code:
Controller :
company.find({}, function(err, companies) {
if (err){
callback(err);
}
else{
callback(null, companies);
}
});
Route :
app.get('/companies', isLoggedIn,function(req, res) {
companyCtrl.companyList(function(err, companies){
res.render('companies',{companies:companies});
});
});
Jade Template :
each val in companies
tr
td(data-field="state" data-checkbox="true" ) ID
td(data-field="id" data-sortable="true")= val.id
td(data-field="name" data-sortable="true")= val.name
In the above example i have used .find method in controller to fetch the documents in the collection and send them back to the route with callback function and jade display the results in the frontend
I know how to...
Remove a single document.
Remove the collection itself.
Remove all documents from the collection with Mongo.
But I don't know how to remove all documents from the collection with Mongoose. I want to do this when the user clicks a button. I assume that I need to send an AJAX request to some endpoint and have the endpoint do the removal, but I don't know how to handle the removal at the endpoint.
In my example, I have a Datetime collection, and I want to remove all of the documents when the user clicks a button.
api/datetime/index.js
'use strict';
var express = require('express');
var controller = require('./datetime.controller');
var router = express.Router();
router.get('/', controller.index);
router.get('/:id', controller.show);
router.post('/', controller.create);
router.put('/:id', controller.update);
router.patch('/:id', controller.update);
router.delete('/:id', controller.destroy);
module.exports = router;
api/datetime/datetime.controller.js
'use strict';
var _ = require('lodash');
var Datetime = require('./datetime.model');
// Get list of datetimes
exports.index = function(req, res) {
Datetime.find(function (err, datetimes) {
if(err) { return handleError(res, err); }
return res.json(200, datetimes);
});
};
// Get a single datetime
exports.show = function(req, res) {
Datetime.findById(req.params.id, function (err, datetime) {
if(err) { return handleError(res, err); }
if(!datetime) { return res.send(404); }
return res.json(datetime);
});
};
// Creates a new datetime in the DB.
exports.create = function(req, res) {
Datetime.create(req.body, function(err, datetime) {
if(err) { return handleError(res, err); }
return res.json(201, datetime);
});
};
// Updates an existing datetime in the DB.
exports.update = function(req, res) {
if(req.body._id) { delete req.body._id; }
Datetime.findById(req.params.id, function (err, datetime) {
if (err) { return handleError(res, err); }
if(!datetime) { return res.send(404); }
var updated = _.merge(datetime, req.body);
updated.save(function (err) {
if (err) { return handleError(res, err); }
return res.json(200, datetime);
});
});
};
// Deletes a datetime from the DB.
exports.destroy = function(req, res) {
Datetime.findById(req.params.id, function (err, datetime) {
if(err) { return handleError(res, err); }
if(!datetime) { return res.send(404); }
datetime.remove(function(err) {
if(err) { return handleError(res, err); }
return res.send(204);
});
});
};
function handleError(res, err) {
return res.send(500, err);
}
DateTime.remove({}, callback) The empty object will match all of them.
.remove() is deprecated. instead we can use deleteMany
DateTime.deleteMany({}, callback).
In MongoDB, the db.collection.remove() method removes documents from a collection. You can remove all documents from a collection, remove all documents that match a condition, or limit the operation to remove just a single document.
Source: Mongodb.
If you are using mongo sheel, just do:
db.Datetime.remove({})
In your case, you need:
You didn't show me the delete button, so this button is just an example:
<a class="button__delete"></a>
Change the controller to:
exports.destroy = function(req, res, next) {
Datetime.remove({}, function(err) {
if (err) {
console.log(err)
} else {
res.end('success');
}
}
);
};
Insert this ajax delete method in your client js file:
$(document).ready(function(){
$('.button__delete').click(function() {
var dataId = $(this).attr('data-id');
if (confirm("are u sure?")) {
$.ajax({
type: 'DELETE',
url: '/',
success: function(response) {
if (response == 'error') {
console.log('Err!');
}
else {
alert('Success');
location.reload();
}
}
});
} else {
alert('Canceled!');
}
});
});
MongoDB shell version v4.2.6
Node v14.2.0
Assuming you have a Tour Model: tourModel.js
const mongoose = require('mongoose');
const tourSchema = new mongoose.Schema({
name: {
type: String,
required: [true, 'A tour must have a name'],
unique: true,
trim: true,
},
createdAt: {
type: Date,
default: Date.now(),
},
});
const Tour = mongoose.model('Tour', tourSchema);
module.exports = Tour;
Now you want to delete all tours at once from your MongoDB, I also providing connection code to connect with the remote cluster.
I used deleteMany(), if you do not pass any args to deleteMany(), then it will delete all the documents in Tour collection.
const mongoose = require('mongoose');
const Tour = require('./../../models/tourModel');
const conStr = 'mongodb+srv://lord:<PASSWORD>#cluster0-eeev8.mongodb.net/tour-guide?retryWrites=true&w=majority';
const DB = conStr.replace('<PASSWORD>','ADUSsaZEKESKZX');
mongoose.connect(DB, {
useNewUrlParser: true,
useCreateIndex: true,
useFindAndModify: false,
useUnifiedTopology: true,
})
.then((con) => {
console.log(`DB connection successful ${con.path}`);
});
const deleteAllData = async () => {
try {
await Tour.deleteMany();
console.log('All Data successfully deleted');
} catch (err) {
console.log(err);
}
};
Your_Mongoose_Model.deleteMany({}) can do the job
References:
https://mongoosejs.com/docs/api.html#query_Query-deleteMany
https://www.geeksforgeeks.org/mongoose-deletemany-function/
How do I programmatically create a database using the MongoDB Node.JS driver?
This looks promising, but I'm not sure how to connect to with the admin credentials and create a new database.
var db = new Db('test', new Server('locahost', 27017));
// Establish connection to db
db.open(function(err, db) {
assert.equal(null, err);
// Add a user to the database
db.addUser('user3', 'name', function(err, result) {
assert.equal(null, err);
// Authenticate
db.authenticate('user3', 'name', function(err, result) {
assert.equal(true, result);
// Logout the db
db.logout(function(err, result) {
assert.equal(true, result);
// Remove the user
db.removeUser('user3', function(err, result) {
assert.equal(true, result);
db.close();
});
});
});
});
});
in mongodb databases and collections are created on first access. When the new user first connects and touches their data, their database will get created then.
This seems to work.
var Db = require('mongodb').Db,
Server = require('mongodb').Server;
var db = new Db('test', new Server('localhost', 27017));
db.open(function (err, db) {
if (err) throw err;
// Use the admin database for the operation
var adminDb = db.admin();
adminDb.authenticate('adminLogin', 'adminPwd', function (err, result) {
db.addUser('userLogin', 'userPwd', function (err, result) {
console.log(err, result);
});
});
});
Try as below:
var adminuser = "admin";
var adminpass = "admin";
var server = "localhost";
var port = 27017;
var dbName = "mydatabase";
var mongodb = require('mongodb');
var mongoClient = mongodb.MongoClient;
var connString = "mongodb://"+adminuser+":"+adminpass+"#"+server+":"+port+"/"+dbName;
mongoClient.connect(connString, function(err, db) {
if(!err) {
console.log("\nMongo DB connected\n");
}
else{
console.log("Mongo DB could not be connected");
process.exit(0);
}
});