gridfs-stream Image post generated collections but request never finishes - node.js

I am trying to upload an image to my MongoDB. I'm using Mongoose, gridfs-stream and some other packages I was told to install (I'm relatively new to the whole MEAN ecosystem)
The request seems to go through fine, and the collections used for fs-stream do get auto added to my db, but the request always seems to time out with no error being returned and nothing being logged by nodemon.
Here is my code:
const router = require('express').Router();
const database = require('../config/database');
var mongoose = require('mongoose');
var Grid = require('gridfs-stream');
Grid.mongo = mongoose.connection;
var conn = mongoose.connection;
var gfs = new Grid(conn.db, mongoose.mongo);
router.get('/', function(req, res) {
res.send("Greetings!");
})
router.post('/img', function(req, res) {
var part = req.files.fileField;
var writeStream = gfs.createWriteStream({
filename: part.name,
mode: 'w',
content_type:part.mimetype
});
writeStream.on('close', function() {
return res.status(200).send({
message: 'Success'
});
writeStream.end();
})
});
I have tried running the mongodb locally, and on mlab, I have also tried images of varying sizes, most of which were less than 10MB and some less than 1MB. I'm at a loss of where to go from here as my research into the matter has also offered no answers.

Related

Why I cant retrive data from mongodb in my simple web application?

I am trying to connect mongodb to my express nodejs web application. I am fresh new to nodejs. I am following this tutorial video but I couldn't complete it due to the connection of mongodb.
the app.js code I have:
var express = require('express');
var app = express();
var bodyParser = require('body-parser');
var mongoose = require('mongoose');
Genre = require('./models/genre');
let conn = mongoose.connection;
conn.openUri('mongodb://localhost/bookstore');
conn.on('error', err => console.error('mongodb connection error',
err));
conn.on('connected', () => console.info(`Connected to mongodb`));
conn.on('disconnected', () => console.info('Disconnected from
mongodb'));
app.get('/', function(req, res){
res.send('Hello World');
});
app.get('api/genres', function(req , res){
Genre.getGenres(function(err, genres){
if(err){
throw err;
}
res.json(genres);
})
});
app.listen(3666);
console.log('Server Running On http://localhost:3666');
and this is the genre.js
var mongoose = require('mongoose');
var genreSchema = mongoose.Schema({
name:{
type: String,
requires: true
},
create_date:{
type: Date,
default: Date.now
}
});
var Genre = module.exports = mongoose.model('Genre', genreSchema);
module.exports.getGenres = function(callback, limit){
Genre.find(callback).limit(limit);
}
and this is a picture of the database in the terminal
https://i.stack.imgur.com/S3gFb.png
And the information in genres collection in the database
https://i.stack.imgur.com/sJFE6.png
Once I open the main page I get the Hello World but once I add api/genres which I should get the data from mongodb I get this error
https://i.stack.imgur.com/B4c8o.png
and this is the files structures
https://i.stack.imgur.com/okHIN.png
I know this is a basic question but I couldnt figured out I check on google there are others way to connect to the database but I need to know why this particular way which I just followed from the tutorial video havent worked.
As you noticed I am a new to nodejs web development so if you could suggest websites or youtube channels to get me start it I would appreciate it.
It seems that it is not a db connection problem. Route matching http://localhost:3666/api/genres is not found in your application. Replace api/genres with /api/genres and I guess everything will work properly

How to connect my backend with my frontend with angular2 and ionic2 using gridFs?

I have created a file in my database using gridFs. The file is as follows:
storeAudio.js
var mongoose = require('mongoose');
var fs = require('fs');
var Grid = require('gridfs-stream');
Grid.mongo=mongoose.mongo;
//establish mongoDB connection
mongoose.Promise = global.Promise;
var conn = mongoose.createConnection('mongodb://localhost:27017/aHolyBoly');
conn.once('open',function(){
var gfs = Grid(conn.db);
// var db = new mongo.Db('aHolyBoly', new mongo.Server("127.0.0.1", 27017));
//var gfs = Grid(db, mongo);
var writeStream = gfs.createWriteStream({
filename:'song1.mp3'
});
fs.createReadStream('../list/hero.mp3').pipe(writeStream);
writeStream.on('close',function(file){
console.log(file.filename +'Written to db');
});
});
Now, I want to make an API using express and node so that I can connect my Backend with Frontend using Ionic2 and Angular2.
So I saw this tutorial:
https://www.joshmorony.com/building-a-review-app-with-ionic-2-mongodb-node/
Now in this tutorial, the HTTP verbs GET, POST etc are used to make the API calls and then it is used as a provider.So is this the way to continue with my project? And if this is the way then I have some questions which are below:
In the link mentioned above there is server.js file. In that file a code as mongoose.connect('mongodb://localhost/reviewking'); Why this is used again if already used in my file storeAudio.js?
Secondly, should the HTTP verbs be used in the similar fashion using gridFs?
Note: I am using first time everything (except ionic2 and angular2).Please let me know if any more inputs should be provided. And Sorry for the mistakes if found in this post.
Here is a sample function from one of my providers in an ionic 3 App which is making a call to my API:
getClients(){
let headers = new Headers();
headers.append('Authorization', this.authService.token);
this.http.get('https://ptassist.herokuapp.com/api/auth/' + this.authService.user._id, {headers: headers})
.map(res => res.json())
.subscribe(data => {
this.clientlist = data;
console.log(this.clientlist);
}, (err) => {
console.log(err);
});
}
As for your other query about the mongoose connection, I'm not entirely sure, have you code your code on github etc?

NodeJS Mongoose handle database connection failed exception

I'm building a restful web service api using NodeJS.It uses Mongoose as ODM and using MongoDB for backend.
Below i will explain my scenario
I started nodejs server
After that i shutdown the MongoDB database.
Then call the GET api call,it doest catch any errors and api call get hang.
database config in main.js file
var mongoose = require('mongoose');
var uri = 'mongodb://localhost/mydb';
mongoose.Promise = global.Promise;
var options = { server: {socketOptions: { keepAlive: 300000, connectTimeoutMS: 10000 } } } ;
mongoose.connect(uri,options);
var db = mongoose.connection;
db.on('error',console.log.bind(console,'connection refused !!!!!'));
db.once('open', console.log.bind(console,'connection success !!!!!'));
this is my basic GET call
var express = require('express');
var router = express.Router();
var mongoose = require('mongoose');
var rootRes = require('../model/rootresources.js');
router.get('/', function(req, res, next) {
rootRes.find({},function (err, rootResource) {
if (err){
console.log('Error occurd !!!') }
res.json(rootResource);
});
});
Even database connection failed, the code does not goes to error block. So didn't capture the database refuse when database connection is failed in the API call.
I want to capture that error and send internal server error (code:500) to client. I tried to find the solution but still could not find it
Any solutions or do i made a mistake ?
Thank you
Amila
Did you put the two parts of code in the same file(ie. main.js) or two different files.
put them in the same file, and run node main.js do throw exceptions.
// main.js
var mongoose = require('mongoose');
var uri = 'mongodb://localhost/mydb';
mongoose.Promise = global.Promise;
var options = { server: {socketOptions: { keepAlive: 300000,
connectTimeoutMS: 10000 } } } ;
mongoose.connect(uri,options);
var db = mongoose.connection;
db.on('error',console.log.bind(console,'connection refused !!!!!'));
db.once('open', console.log.bind(console,'connection success !!!!!'));
var express = require('express');
var router = express.Router();
var mongoose = require('mongoose');
var rootRes = require('../model/rootresources.js');
router.get('/', function(req, res, next) {
rootRes.find({},function (err, rootResource) {
if (err){
console.log('Error occurd !!!') }
res.json(rootResource);
});
});
exceptions are:
connection refused !!!!! { MongoError: failed to connect to server [localhost:27017] on first connect [MongoError: connect ECONNREFUSED 127.0.0.1:27017]
etc...
So, I think maybe you put codes about express in a file like index.js and codes about mongoose connection in another file. And just run node index.js in command line. While running codes in index.js will not include codes in other files, codes in main.js will not be executed. As the result, there is no error info.
Updates
Two ways of I know two ways of doing this:
1.In main.js create function which creates connection to database and returns a instance of db so that you can call it function in you main code.
// main.js like this
var mongoose = require('mongoose');
function createConnection(url) {
mongoose.connect(url,options);
var db = mongoose.connection;
db.on('error',console.log.bind(console,'refused !!!!!'));
db.once('open', console.log.bind(console,'success !!!!!'));
return db;
}
// export function
module.exports = createConnection;
// in your index.js
var createConnection = require('./main.js');
var db = createConnection(url);
// other codes here
2.Using require or vm to compile and run javascipt code. You can find vm api detail here
//main.js
var mongoose = require('mongoose');
var uri = 'mongodb://localhost/mydb';
mongoose.Promise = global.Promise;
var options = { server: {socketOptions: { keepAlive: 300000,
connectTimeoutMS: 10000 } } } ;
mongoose.connect(uri,options);
var db = mongoose.connection;
db.on('error',console.log.bind(console,'connection refused !!!!!'));
db.once('open', console.log.bind(console,'connection success !!!!!'));
// index.js
// require will load file and execute automaticly
var scriptSrc = require('./main');
// other codes here
You can think of the second way as using eval('var mongoose = require('mongoose');
var uri = 'mongodb://localhost/mydb'; etc...)
mongoose connection do not happen unless you hit a request. so its best you handle it in your first request middleware. see code insight bellow.
module.exports = function () {
return function (req, res, next) {
mongoose.connect(URL, MONGO_OPTIONS);
mongoose.connection
.once('open', () => { })
.on('error', (error) => {
res.status(401).json({});
});
...
Then pass the middleware above to your router: let me know if you need more explanation
router.get('/', myMiddleware(){})

What is the best practice to connect/disconnect to a database?

I'd like to know how to work with connectivity to a database in MEAN stack application. In particular, when should I create a connection to a database and when should I destroy a connection to a database. Should I create and destroy a connection on every new HTTP request or should I store a once created connection and use it for any subsequent requests as long as possible. I use Mongoose as a modeling tool.
Here is an example.
This is my routes.js file with a route /index. A request to this route should fetch some date from MongoDb database. It bothers me how I connect and disconnect to a database now. Yes, I connect and disconnect to a database exactly as written in Mongoose docs, but it it the right way to do it in a serious production environment?
var express = require('express');
var router = express.Router();
var config = require('./db-config');
// I create a Mongoose instance as a module object,
// as opposite to create it in every request handler function below.
var mongoose = require('mongoose');
var productSchema = require('../db/productSchema'); // model schema is also a module-wide object
// And here is a request handler function.
// It is called on every request as a brand new.
// I create and destroy a database connection inside this request handler
router.get('/index', function(req, res, next) {
// I connect to a database on every request.
// Do I need to do it here in a request handler?
// May I do it outside of this request handler on a module-wide level?
mongoose.connect('mongodb://my_database');
// I create a new connection here in a request handler.
// So it lives only during this request handler run.
// Is this the right way? May I do it outside of this request handler
// on a module-wide level and somehow keep this connection and use it
// in every subsequent requests to this or any other route in the app?
var db = mongoose.connection;
db.on('connecting', function() {
console.log('connecting');
});
db.on('connected', function() {
console.log('connected');
});
db.on('open', function() {
console.log('open');
});
db.on('error', console.error.bind(console, 'connection error'));
db.once('open', function(cb) {
var Product = mongoose.model('Product', productSchema);
Product.find({category: "books"}, function(err, prods) {
if (err) return console.error(err);
// I close a connection here in a callback.
// As soon as successfully fetched the data.
// Do I need to close it after every request?
// What is the right place and time to do it?
db.close(disconnect);
res.json(prods);
});
});
})
Found some good answers:
https://softwareengineering.stackexchange.com/questions/142065/creating-database-connections-do-it-once-or-for-each-query
What are best practices on managing database connections in .NET?
Its best practice to have your db connection in a separate module (db.js)
var mongoose = require('mongoose')
mongoose.connect('mongodb://localhost/dbname', function(){
console.log('mongodb connected')
})
module.exports = mongoose
Each model should have a separate module that takes in the db connection (post.js)
var db = require('../db.js')
var Post = db.model('Post', {
username: {type: String, required: true},
body: {type: String, required: true},
date: { type: Date, required: true, default: Date.now }
})
module.exports = Post
Then whenever you need to use that data set just require it and make calls
var Post = require('/models/post')
Post.save()
Post.find()
This is an opinion based question I'd say. What I use for my app is
app.get('/', function (req, res) {
res.sendfile('index.html');
});
mongoose.connect('mongodb://localhost:27017/my_db');
This way I create a connection once rather than on every HTTP request. Your way should work fine but it seems you will have to connect and disconnect the db to your app way too many times specially when the app is in development.
You want your connection to act like a singleton so as mentioned in the answer above it makes sense to do it outside of, and preferable before your routes:
var compression = require('compression');
var express = require('express');
var app = express();
var port = process.env.PORT || 8080;
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var session = require('express-session');
...
app.use(compression());
// db
var mongoose = require('mongoose');
var configDB = require('./config/database.js');
mongoose.connect(configDB.url); // connect to our database
config/database.js:
module.exports = {
'url' : '#localhost:27017/dbname'
};
This is my solution :
import express from 'express';
import mongoose from 'mongoose';
import { name } from '../package.json';
import * as localconfig from './local-config';
import debug from 'debug';
debug(name);
const app = express();
const port = process.env.PORT || 3000;
const mongoUrl = localconfig.credentials.MONGO_URL;
import usersRoutes from './routes/users/user-routes';
app.use('/v1/users', usersRoutes);
mongoose.connect(mongoUrl)
.then(() => {
debug('DB connection successful');
app.listen(port, '0.0.0.0', () => {
debug(`Running on port ${port}`);
});
})
.catch((err) => {
debug(err);
});
You should first check weather the connection is successful or not and only then listen to a certain port. This is my app.js file where all the routes are loaded, so you do not have to call the db connection in all your files. You have a single config file where all the config is done. Your router file user-routes.js will look something similar to this:
import express from 'express';
import User from '../models/user'
const router = express.Router();
router.get('/', (req, res, next) => {
User.find()
.then((response) => res.json(response))
.catch((err) => next(err));
});
module.exports = router;

Read file from gridfs in mongodb

I have this route for this task:
var mongoose = require('mongoose');
var gfs;
var Grid = require('gridfs-stream');
var connection = mongoose.createConnection(mongodb://localhost/images);
connection.once('open', function () {
gfs = Grid(connection.db, mongoose.mongo);
});
app.get('/api/image/:file', function(req, res) {
res.set('Content-Type', getType(req.params.file));
gfs.createReadStream({
filename: '/api/image/'+req.params.file
}).pipe(res);
});
For some reason it's really slow, can't figure why is that. Even when i run it on local. If i use something like mongoose-fs or something familiar it will be faster?
Also every time image is loading, it don't keep that image in cache(every time is 200). How can i tell to node that this have to be cached? At the moment i have express way app.set('view cache', true);.

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