As I used app.get to query in urls as localhost:3000/data?country=Italy and I get the data stored in MongoDb. How can I use app.post request method to query the parameters and get the data? I'm unable to find the proper solution and I'm completely new to this.
const express = require("express");
const mongoose = require("mongoose");
const Schema = mongoose.Schema;
const url = "mongodb://localhost:27017/source_scrapped_data";
const app = express();
mongoose.connect(url, { useNewUrlParser: true });
// mongoose.Promise = global.Promise;
const db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', () => {
console.log("Connected to mongo");
});
const covid_data = mongoose.model('Covid',
new Schema({}),
'covid_data');
app.get("/data", (req, res) => {
const continent = req.query.continent;
const country = req.query.country;
covid_data.find({'Continent':continent,'Country':country},(err,docs)=>{
if(err){
console.log(err)
res.send("no data found",err)
}
else{
console.log(err)
res.send(docs)
}
});
});
module.exports = app;
app.post("/data", (req, res) => {
const continent = req.body.continent;
const country = req.body.country;
covid_data.find({'Continent':continent,'Country':country},(err,docs)=>{
if(err){
console.log(err)
res.send("no data found",err)
}
else{
console.log(err)
res.send(docs)
}
});
});
This is how you can get data in post request that is passed in the body of the request.
This is not the standard practice you should not use post request to do get a query. Always use POST method to put some data in the database.
Related
This is my Code
const express = require('express');
const { MongoClient } = require('mongodb');
const cors = require('cors');
require('dotenv').config()
const app = express();
const port = 5000;
// middle ware
app.use(cors());
app.use(express.json());
const uri = `mongodb+srv://${process.env.DB_USER}:${process.env.DB_PASS}#cluster0.84pml.mongodb.net/myFirstDatabase?retryWrites=true&w=majority`;
const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
client.connect(err => {
const collection = client.db("carMechanic").collection("services");
// perform actions on the collection object
client.close();
});
async function run() {
try {
await client.connect();
const database = client.db("carMechanic");
const servicesCollection = database.collection("services");
// post API
app.post('/services', async (req, res) => {
const service = req.body;
// console.log('hit the post is', service);
const result = await servicesCollection.insertOne(service);
console.log(result);
res.send('post hitted')
});
}
finally {
// await client.close();
}
}
run().catch(console.dir);
app.get('/', (req, res) => {
res.send('Running Genius Server');
});
app.listen(port, () => {
});
And This is the error message
G:\web_projects\practice\node\module-65-Genius-car\backend\node_modules\mongodb\lib\utils.js:690
throw new error_1.MongoRuntimeError(`illegal state transition from [${target.s.state}] => [${newState}], allowed: [${legalStates}]`);
^
MongoRuntimeError: illegal state transition from [closed] => [connected], allowed: [closed,connecting]
at stateTransition (G:\web_projects\practice\node\module-65-Genius-car\backend\node_modules\mongodb\lib\utils.js:690:19)
at G:\web_projects\practice\node\module-65-Genius-car\backend\node_modules\mongodb\lib\sdam\topology.js:226:21
at G:\web_projects\practice\node\module-65-Genius-car\backend\node_modules\mongodb\lib\cmap\connection_pool.js:272:25
at handleOperationResult (G:\web_projects\practice\node\module-65-Genius-car\backend\node_modules\mongodb\lib\sdam\server.js:363:9)
at MessageStream.messageHandler (G:\web_projects\practice\node\module-65-Genius-car\backend\node_modules\mongodb\lib\cmap\connection.js:479:9)
at MessageStream.emit (events.js:375:28)
at processIncomingData (G:\web_projects\practice\node\module-65-Genius-car\backend\node_modules\mongodb\lib\cmap\message_stream.js:108:16)
at MessageStream._write (G:\web_projects\practice\node\module-65-Genius-car\backend\node_modules\mongodb\lib\cmap\message_stream.js:28:9)
at writeOrBuffer (internal/streams/writable.js:358:12)
at MessageStream.Writable.write (internal/streams/writable.js:303:10)
The problem is this line:
client.connect(err => {
const collection = client.db("carMechanic").collection("services");
// perform actions on the collection object
client.close();
});
you don't need this because you made connection to the database later
I answered myself.
I had made a mistake, that was I wrote the extra code given below.
client.connect(err => {
const collection = client.db("carMechanic").collection("services");
// perform actions on the collection object
client.close();
});
Because this has already been declared inside of my function.
await client.connect();
const database = client.db("carMechanic");
const servicesCollection = database.collection("services");
When I remove this--
client.connect(err => {
const collection = client.db("carMechanic").collection("services");
// perform actions on the collection object
client.close();
});
the code is working well.
I have my code below and works as is. A few things:
Install dependencies again if needed
I am using the sample airbnb db they provide in Atlas service on cloud.mongodb.com
Change username:0987654321 to your own username and password where 'username' is the username and 0987654321 is the password.
Run() works fine locally but it's not straight forward to have a local method start a server endpoint and keep track of it or vice versa. For that you need good chaining
So only USE the run method to test locally and it works fine or use the express endpoints to test via your app client side or curl or postman and that works too independently.
Heres my whole server file:
const express = require('express');
const { MongoClient } = require('mongodb');
const cors = require('cors');
// middle ware
const app = express();
const port = 5000;
// middle ware
app.use(cors());
app.use(express.json());
const uri = "mongodb://username:0987654321#cluster0-shard-00-00.czraf.mongodb.net:27017,cluster0-shard-00-01.czraf.mongodb.net:27017,cluster0-shard-00-02.czraf.mongodb.net:27017/sample_airbnb?ssl=true&replicaSet=atlas-wmfxrm-shard-0&authSource=admin&retryWrites=true&w=majority";
async function run(){
//1 connect
const client = await MongoClient.connect(uri, {
useNewUrlParser: true,
useUnifiedTopology: true,
});
//2 set db and collection
const collection = client.db("sample_airbnb").collection("listingsAndReviews");
// perform actions on the collection object
//3 CREATE
let doc = {
"_id":"100009090",
"listing_url":"https://www.airbnb.com/rooms/100009190",
"name":"Ribeira Charming Duplex",
"summary":"Fantastic duplex apartment with three bedrooms, located in the historic area of Porto, Ribeira (Cube)",
"neighborhood_overview":"In the neighborhood of the river, you can",
"price":"250gbp"
}
//4.0 POST INDEPENDENTLY
//collection.insertOne(doc).then(doc => { console.log('inserted id is: ', doc.insertedId)});
//FIND ONE
//const result = await collection.find( {_id: {$eq: "10006546"} }).toArray();
//FIND MANY
//const many = await collection.find( {_id: { $in: ["10006546", "100009090"] } } ).toArray();
//LOGGER
//console.log(many)
client.close();
};
//server methods
//get route
app.get('/', (req, res) => {
res.send('Running Genius Server');
});
//get docs
app.get('/docs', async (req, res) => {
//FIND MANY
const many = await collection.find( {_id: { $in: ["10006546", "100009090"] } } ).toArray();
//LOGGER
console.log(many)
res.send('docs returned', JSON.stringify(many));
});
//add docs
app.post('/test', async (req, res) => {
//get data through body
const service = req.body.name;
//get data through query params in url
const qparam = req.query.name;
const _id = req.query.id;
//build your doc
let doc = {service:qparam, _id: _id};
//connect to db and collection
//2 set db and collection
//1 connect
const client = await MongoClient.connect(uri, {
useNewUrlParser: true,
useUnifiedTopology: true,
});
const collection = client.db("sample_airbnb").collection("listingsAndReviews");
collection.insertOne(doc).then(doc => { console.log('inserted id is: ', doc.insertedId)});
// /res.status(status).send(body)
res.send(JSON.stringify(service + ' ' + qparam));
});
app.listen(port, () => {
});
run();
Im trying to insert / Post data in my mongoDb database using exrpess and through Postman, however im at loss in how to perform it. I defined an url being "/api/post" which executes a request of post and asks for now only the "title". When I use postman to create some data, it returns to me as "undefined" with an empty object.
Here is the code:
const {MongoClient} = require('mongodb');
const express = require("express");
const mongoose = require("mongoose")
const app = express()
async function main() {
const uri = "mongodb+srv://dbUser1:<password>#movies.uxfxv.mongodb.net/Movies?retryWrites=true&w=majority";
const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
const { schema } = mongoose;
MongoClient.connect(uri, function(err, db) {
if (err) throw err;
let dbo = db.db("Movies");
dbo.collection("Movies").find({}).toArray(function(err, result) {
if (err) throw err;
console.log(result);
app.get("/", (req, res) => {
res.json(result)
})
app.post("/api/post", (req, res) => {
const title = req.body
console.log(title)
res.json({
title
})
})
db.close()
})
})
main().catch(console.error)
Here is the Postman Req.
I would appreciate any feedback an help, thanks!
I'm trying to get data from a collections database in my MongoDB using Node, which I've done successfully. My only problem is how to render the obtained data from the collections and posting it into the express app.
const { MongoClient } = require('mongodb');
const express = require("express");
const app = express()
async function main() {
const uri = "mongodb+srv://dbUser1:<password>#movies.uxfxv.mongodb.net/Movies?retryWrites=true&w=majority";
const client = new MongoClient(uri, {
useNewUrlParser: true,
useUnifiedTopology: true
});
MongoClient.connect(uri, function(err, db) {
if (err) throw err;
let dbo = db.db("Movies");
dbo.collection("Movies").find({}).toArray(function(err, result) {
if (err) throw err;
console.log(result);
db.close()
})
})
}
main().catch(console.error)
I solved my own problem by just performing an app.get() in the part were it says Mongoclient.connect() and the rest is done by logic, it displays now in the express and in postman as well.
const {MongoClient} = require('mongodb');
const express = require("express");
const app = express()
async function main() {
const uri = "mongodb+srv://dbUser1:<password>#movies.uxfxv.mongodb.net/Movies?retryWrites=true&w=majority";
const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
MongoClient.connect(uri, function(err, db) {
if (err) throw err;
let dbo = db.db("Movies");
dbo.collection("Movies").find({}).toArray(function(err, result) {
if (err) throw err;
console.log(result);
app.get("/", (req, res) => {res.json(result)})
db.close()
})
})
app.listen(4000, function() {
console.log("listening to port 4000)
}
main().catch(console.error)
Here is another way:
const MongoClient = require('mongodb').MongoClient;
const express = require('express');
const app = express();
const url = 'mongodb://localhost:27017';
const dbName = 'test';
const port = 3000;
app.listen(port);
// Type this in your browser to see db data: http://localhost:3000/
app.get('/', function(req, res) {
const client = new MongoClient(url, { useUnifiedTopology: true });
client.connect(function(err) {
console.log("Connected to server.");
const db = client.db(dbName);
db.collection("books")
.find({})
.toArray(function(err, result) {
if (err) throw err;
client.close();
console.log("Done reading db.");
res.send(JSON.stringify(result));
});
});
});
I'm trying to figure out why my data hasn't been saving in MongoDB, despite calling the .save() method. I'm aware that this is an asynchronous process, but as you can see below, I set up a callback using .then() - which executes without error. The target database has a single empty collection in it, so I was expecting the data to appear there or in a new collection, neither of which happened. Here's the code for my index.js file:
const express = require('express');
const mongoose = require('mongoose');
const { body, validationResult } = require('express-validator/check');
const router = express.Router();
const Registration = mongoose.model('Registration');
router.get('/', (req, res) => {
res.render('form', { title: 'Registration Form'});
});
router.post('/',
[body('name')
.isLength(1)
.withMessage('Please enter a name.'),
body('email')
.isLength(1)
.withMessage('Please enter an email address.')
],
(req, res) => {
//console.log(req.body);
const errors = validationResult(req);
if(errors.isEmpty)
{
const registration = new Registration(req.body);
//registration.markModified('collection_1');
registration.save()
.then(() => { res.send('Thank you for your registration!'); })
.catch(() => { res.send('Sorry! Something went wrong.'); });
} else {
// re-renders form with error message
res.render('form', {
title: 'Registration form',
errors: errors.array(),
data: req.body,
});
}
});
module.exports = router;
Let me know if any other files would be useful. Any assistance would be greatly appreciated.
EDIT: Here's my start.js file.
require('dotenv').config();
const mongoose = require('mongoose');
require('./models/Registration');
mongoose.connect(process.env.DATABASE, { useMongoClient: true });
mongoose.Promise = global.Promise;
mongoose.connection
.on('connected', () => {
console.log(`Mongoose connection open on ${process.env.DATABASE}`);
})
.on('error', (err) => {
console.log(`Connection error: ${err.message}`);
});
const app = require('./app');
const server = app.listen(3000, () => {
console.log(`Express is running on port ${server.address().port}`);
});
I am desperately trying to create a connection with mongoDB with the MEAN stack, using mongoose.
My MongoDB instance (mongod) is running and I can use mongo.exe and tested it by inserting some documents, it worked fine. But I have problems to create a connection to MongoDB with mongoose, and inserting a document with the .save() method does not work either...
I first wanted to try my POST method, created a function and tested it by creating some values in POSTMAN. But no documents were inserted in my MongoDB datbase..
This is my app.js file:
var express = require('express');
var app = express();
var bodyParser = require("body-parser");
var morgan = require("morgan");
//var routes = require('./routes');
//var cors = require('cors')
//configure app
app.use(morgan('dev')); //log requests to the console
//configure body parser
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
var port = process.env.PORT || 5000;
//DATABASE SETUP
var mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/DNZ'); //connect to uor datbaase
//Handle the connection event
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function() {
console.log("DB connection alive");
});
//DNZ models live here
var FA = require('./models/DNZmodels/FA');
//ROUTES FOR OUR API
//=============================================================================
//create our router
var router = express.Router();
//middleware to use for all requests
router.use(function(req, res, next) {
// do logging
console.log('Something is happening.');
console.log('Today is:', Date())
next();
});
//test route to make sure everything is working (accessed at GET http://localhost:5000/DNZ/)
router.get('/', function(req, res) {
res.json({ message: 'Welcome to DNZ API!' });
});
//on routes that end in /FA
//----------------------------------------------------
router.route('/FA')
// create a FA (accessed at POST http://localhost:8080/DNZ/FA)
.post(function(req, res) {
//console.log(req.body);
//console.log(req.body.params);
//res.setHeader('Content-Type', 'application/json')
res.send(JSON.stringify(req.body));
/*
var timestamp = req.body.Timestamp;
var prognostizierterBetriebswert = req.body.PrognostizierterBetriebswert;
var posFlexPot = req.body.posFlexPot;
var negFlexPot = req.body.negFlexPot;
var leistungsuntergrenze = req.body.Leistungsuntergrenze;
var leistungsobergrenze = req.body.Leistungsobergrenze;
var posGesEnergie = req.body.posGesEnergie;
var negGesEnergie = req.body.negGesEnergie;
var preissignal = req.body.Preissignal;
var dummy1 = req.body.Dummy1;
var dummy2 = req.body.Dummy2;
var dummy3 = req.body.Dummy3;
*/
var fa = new FA();
fa.name = req.body.name;
console.log("Hier erscheint var fa:", fa);
//console.log(Dummy1);
//res.send(JSON.stringify(timestamp));
// create a new instance of the FA model
/*
var fa = new FA({
Timestamp: timestamp,
Leistungsuntergrenze: leistungsuntergrenze,
Leistungsobergrenze:leistungsobergrenze,
PrognostizierterBetriebswert :prognostizierterBetriebswert,
posFlexPot: posFlexPot,
negFlexPot:negFlexPot,
posGesEnergie: posGesEnergie,
negGesEnergie: negGesEnergie,
Preissignal:preissignal,
Dummy1: dummy1,
Dummy2: dummy2,
Dummy3: dummy3
})
*/
//SAVE the new instance
fa.save(function(err) {
if (err) {
console.log(err);
res.status(400);
res.send(err);
}
else {
console.log("debug");
res.status(200);
res.json({ message: 'FA created!' });
}
});
})
// get all the FAs (accessed at GET http://localhost:8080/DNZ/FA)
.get(function(req, res) {
FA.find(function(err, fas) {
if (err)
res.send(err);
res.json(fas);
});
});
//on routes that end in /FA/:FA_id
//----------------------------------------------------
router.route('/FA/:FA_id')
// get the bear with that id
.get(function(req, res) {
FA.findById(req.params.bear_id, function(err, fa) {
if (err)
res.send(err);
res.json(fa);
});
})
// update the bear with this id
.put(function(req, res) {
FA.findById(req.params.FA_id, function(err, fa) {
if (err)
res.send(fa);
//bear.name = req.body.name;
/*
FA.save(function(err) {
if (err)
res.send(err);
res.json({ message: 'FA updated!' });
});
*/
});
})
/*
// delete the bear with this id
.delete(function(req, res) {
FA.remove({
_id: req.params.bear_id
}, function(err, FA) {
if (err)
res.send(err);
res.json({ message: 'Successfully deleted' });
});
});
*/
//REGISTER OUR ROUTES -------------------------------
app.use('/DNZ', router);
//START THE SERVER
//=============================================================================
app.listen(port);
console.log('Magic happens on port ' + port);
/*
// set static directories
app.use(express.static('./dist'));
app.use(cors());
// Define Routes
var index = require('./routes/index');
var users = require('./routes/users');
//Set up routes
routes.init(app)
//run
app.listen(port);*/
console.log('Server started, Listening on port ', port);
I used the "template" from the Bear tutorial:
https://scotch.io/tutorials/build-a-restful-api-using-node-and-express-4
the problem here is already, that there is no message: "DB connection alive". However, in the bear tutorial (whose code I used here), the DB connection is built and I can insert bear documents in the database. However, here it does not work...
and this is my FA Schema model from FA.js:
var mongoose = require("mongoose");
var Schema = mongoose.Schema;
var FASchema = new Schema({
Timestamp: Date,
PrognostizierterBetriebswert: Number,
posFlexPot: Number,
negFlexPot: Number,
Leistungsuntergrenze: Number,
Leistungsobergrenze: Number,
posGesEnergie: Number,
negGesEnergie: Number,
Preissignal: Number,
Dummy1: Schema.Types.Mixed,
Dummy2: Schema.Types.Mixed,
Dummy3: Schema.Types.Mixed
//same: Dummy: {}
});
//var FASchema = new Schema({name: String});
module.exports = mongoose.model("FA", FASchema, 'FA');
console.log("FA wird ausgeführt!");
Anybody got an idea why there is no DB connection created?
when I test your code , the Error (Can't set headers after they are sent) was thrown. you can delete res.send(JSON.stringify(req.body)); and restart service