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How to merge two files API (Node.js)

I am a node.js and MySQL beginner and I just started setting up and trying out some basic code.
I find these two APIs to practice, one is the API for the CRUD database, and the other is the API for judging user login / registration.I tried to merge the APIs of these two files, and the result was a problem. I think the current problem is the configuration file (conf.js).I plan to write a function and then wrap any file and use it again, so that the configuration files may not conflict, but I don’t know how to start.
These are the two API teaching URLs I practiced
http://www.expertphp.in/article/user-login-and-registration-using-nodejs-and-mysql-with-example
https://www.footmark.info/programming-language/nodejs/nodejs-restful-webapi-mysql/
index.js
var express = require("express");
var bodyParser = require("body-parser");
var app = express();
var authenticateController = require("./controllers/authenticate-controller");
var registerController = require("./controllers/register-controller");
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
app.post("/api/register", registerController.register);
app.post("/api/authenticate", authenticateController.authenticate);
app.listen(3000);
app.js
var bodyparser = require("body-parser");
var express = require("express");
var conf = require("./conf");
var functions = require("./functions");
var user = require("./routes/user");
var app = express();
req.body
app.use(bodyparser.urlencoded({ extended: false }));
app.use(bodyparser.json());
//app.use(functions.passwdCrypto);
app.use("/user", user);
app.listen(conf.port, function() {
console.log("app listening on port " + conf.port + "!");
});
authenticate-controller.js
var connection = require('./../conf');
module.exports.authenticate=function(req,res){
var email=req.body.email;
var password=req.body.password;
connection.query('SELECT * FROM user WHERE email = ?',[email], function (error, results, fields) {
if (error) {
res.json({
status:false,
message:'there are some error with query'
})
}else{
if(results.length >0){
if(password==results[0].password){
res.json({
status:true,
message:'successfully authenticated'
})
}else{
res.json({
status:false,
message:"Email and password does not match"
});
}
}
else{
res.json({
status:false,
message:"Email does not exits"
});
}
}
});
}
register-controller.js
var connection = require('../conf');
module.exports.register=function(req,res){
var today = new Date();
var user={
"name":req.body.name,
"email":req.body.email,
"password":req.body.password,
"created_at":today,
"updated_at":today
}
connection.query('INSERT INTO user SET ?',user, function (error, results, fields) {
if (error) {
res.json({
status:false,
message:'there are some error with query'
})
}else{
res.json({
status:true,
data:results,
message:'user registered sucessfully'
})
}
});
}
user.js(models)
var mysql = require("mysql");
var conf = require("../conf");
var connection = mysql.createConnection(conf.db);
var sql = "";
module.exports = {
items: function(req, callback) {
sql = "SELECT * FROM user";
return connection.query(sql, callback);
},
item: function(req, callback) {
sql = mysql.format("SELECT * FROM user WHERE userId = ?", [req.params.id]);
return connection.query(sql, callback);
},
add: function(req, callback) {
sql = mysql.format("INSERT INTO user SET ?", req.body);
return connection.query(sql, callback);
},
delete: function(req, callback) {
sql = mysql.format("DELETE FROM user WHERE userId = ?", [req.params.id]);
return connection.query(sql, callback);
},
put: function(req, callback) {
connection.beginTransaction(function(err) {
if (err) throw err;
sql = mysql.format("DELETE FROM user WHERE userId = ?", [req.params.id]);
connection.query(sql, function(err, results, fields) {
if (results.affectedRows) {
req.body.id = req.params.id;
sql = mysql.format("INSERT INTO user SET ?", req.body);
connection.query(sql, function(err, results, fields) {
if (err) {
connection.rollback(function() {
callback(err, 400);
});
} else {
connection.commit(function(err) {
if (err) callback(err, 400);
callback(err, 200);
});
}
});
} else {
callback(err, 410);
}
});
});
},
patch: function(req, callback) {
sql = mysql.format("UPDATE user SET ? WHERE userId = ?", [req.body, req.params.id]);
return connection.query(sql, callback);
}
};
user.js(routes)
var express = require("express");
var user = require("../models/user");
var router = express.Router();
router
.route("/")
.get(function(req, res) {
user.items(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (!results.length) {
res.sendStatus(404);
return;
}
res.json(results);
});
})
.post(function(req, res) {
user.add(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
res.status(201).json(results.insertId);
});
});
router
.route("/:id")
.get(function(req, res) {
user.item(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (!results.length) {
res.sendStatus(404);
return;
}
res.json(results);
});
})
.delete(function(req, res) {
user.delete(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (!results.affectedRows) {
res.sendStatus(410);
return;
}
res.sendStatus(204);
});
})
.put(function(req, res) {
user.put(req, function(err, results) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (results === 410) {
res.sendStatus(410);
return;
}
user.item(req, function(err, results, fields) {
res.json(results);
});
});
})
.patch(function(req, res) {
user.patch(req, function(err, results, fields) {
if (err) {
res.sendStatus(500);
return console.error(err);
}
if (!results.affectedRows) {
res.sendStatus(410);
return;
}
req.body.id = req.params.id;
res.json([req.body]);
});
});
module.exports = router;
conf.js
var mysql = require("mysql");
var connection = mysql.createConnection({
host: "localhost",
user: "root",
password: "1234",
database: "farmbot",
});
connection.connect(function(err) {
if (!err) {
console.log("Database is connected");
} else {
console.log("Error while connecting with database");
}
});
module.exports = connection;
/*If I comment out the code below, I can execute the login / register API*/
/*Without commenting out, can only perform CRUD on the database*/
module.exports = {
db: {
host: "localhost",
user: "root",
password: "1234",
database: "farmbot"
},
port: 3000
};

You will have to refactor them properly. You will need only once file to begin with. Why using it twice?
Refactor them in one file instead of listening to them on different ports. Once done, you can show the code to us so that we can fix it further if there's an issue.
Start from index.js and merge app.js with it but a bit carefully. I think doing it by yourself you will learn much from it.

How to call mongodb collection getall by node.js?

I wanna take the whole list of notifies from mongo db but it returns empty([]) array also I know that i need callback or shorter way of it . Do you have any idea for collecting any data from mongodb by node.js? If I call this /Notifies method (http://127.0.0.1:5000/Notifies)
var MongoClient = require('mongodb').MongoClient;
var express = require("express");
var app = express();
format = require('util').format;
MongoClient.connect('mongodb://127.0.0.1:27017/Test', function (err, db) {
if (err) {
throw err;
} else {
console.log("successfully connected to the database");
}
db.close();
});
app.get('/Notifies', function (req, res) {
// BAD! Creates a new connection pool for every request
console.log('connected');
MongoClient.connect('mongodb://127.0.0.1:27017/Test', function (err, db) {
if (err) throw err;
var coll = db.collection('Notifies');
var arr = [];
coll.find({}, function (err, docs) {
docs.each(function (err, doc) {
if (doc) {
console.log(doc);
arr.push(doc);
} else {
res.end();
}
});
});
return res.json(arr);
});
});
var port = Number(process.env.PORT || 5000);
app.listen(port, function () {
console.log("Listening on " + port);
})

Don't use for docs.each instead of this use .toArray so it will return directly a array and then use Json.stringify to convert it into json string array
MongoClient.connect('mongodb://127.0.0.1:27017/Test', function (err, db) {
if (err) throw err;
var coll = db.collection('Notifies');
coll.find({}).toArray(function (err, result) {
if (err) {
res.send(err);
} else {
res.send(JSON.stringify(result));
}
})
});

The problem is you are returning the empty array from within the function, before the actual DB operation occurs. You need to move the line return res.json(arr);
into the find function:
app.get('/Notifies', function (req, res) {
// BAD! Creates a new connection pool for every request
console.log('connected');
MongoClient.connect('mongodb://127.0.0.1:27017/Test', function (err, db) {
if (err) throw err;
var coll = db.collection('Notifies');
var arr = [];
coll.find({}, function (err, docs) {
console.log(docs);
docs.each(function (err, doc) {
if (doc) {
console.log(doc);
arr.push(doc);
} else {
res.end();
}
});
return res.json(arr);
});
});
});
Also, for future use, do not reuse variable names in nested functions (you have 3 functions that use the variable err).

Node.js doesn't show results status properly in api

I'm developing a simple rest API in Node.js, and it works middling.
This is my controller code:
...
exports.listById = function(id, callback) {
Course.findById(id, function(err, courses){
if(err){
callback({error: 'Not Found'});
}
else{
callback(courses);
}
});
}
And this is my route:
app.get('/courses/:id', function(req, res){
var id = req.params.id;
courseController.listById(id, function(resp){
res.status(200).json(resp);
});
});
This code works and show results of my collection in mongodb.
But the code below, doesn't show results with postman:
app.get('/courses/:id', function(req, res){
var id = req.params.id;
courseController.listById(id, function(err, resp){
if(err){
res.status(404).send(err);
}
else{
res.status(200).json(resp);
}
});
});

exports.listById = function(id, callback) {
Course.findById(id, function(err, courses){
if(err)
return callback(new Error('Not Found')); // You must return Error by standard
callback(null, courses); // You must set first argument (error) to null
});
}
...
// You can check that id is number
app.get('/courses/:id(\\d+)', function(req, res, next) {
var id = req.params.id;
courseController.listById(id, function(err, resp) {
if(err)
return next(err); // Pass error to error-handler (see link below)
res.status(200).json(resp);
});

Best practice for callback function is first argument as error and second as result.You should
exports.listById = function (id, callback) {
Course.findById(id, function (err, courses) {
if (err) {
callback(error);
}
else {
callback(null, courses);
}
});
}
while your route should look like this:
app.get('/courses/:id', function (req, res) {
var id = req.params.id;
courseController.listById(id, function (error, courses) {
if (error) return res.status(500) // internal server error
// if I remember correctly, sources is empty array if course not found
res.status(200).json(resp);
});
});

Node File System Create Directory and files on post route

I have a dashboard that generates JSON data and saves it as a .json file. This was initially written in PHP but for various reasons we have re-written the application in node. The code below takes the post data and then should check to see if the file exists then if it does update it if not it should create the file and directory.
However it only seems to create the first file and I cannot fathom why it doesn't create the subsequent files as this post route is called once for each post.
the post method looks like this
$.ajax({
type : "POST",
url : '/save/',
dataType : 'json',
data : {
category : settings.category_id,
name : settings.campaignId,
json : JSON.stringify(settings)
}
});
I have debugged and when called all the correct file paths are passed but its almost as if the file isn't being written with the data.
During debugging using node-inspector and nodemon the code loops through all the requested new file names and gives me the error code ENOENT, so it should then follow the create file path.
If you know anything about node and the file system module and feel like helping me out that would be amazing even if it's just pointing me in the direction of some more tutorials, ... anything would be great!
-
'use strict'
const fs = require('fs');
const path = require('path');
const express = require('express');
const router = express.Router();
/* Save Data */
router.post('/', function(req, res) {
if (!(req.body.json && req.body.name && req.body.category)) {
res.sendStatus(400);
return;
}
let dir = 'public/savedData/' + req.body.category;
let filepath = dir + '/' + req.body.name + '.json';
fs.access(filepath, function(error) {
console.log(filepath);
console.log(error.code);
if (error) {
if (error.code == 'ENOENT') {
console.log(error.code);
//debugger;
// Create file since it doesn't exist
createFile(req, res, filepath);
} else {
//debugger;
console.log('access error:', error);
res.sendStatus(500);
}
} else {
//debugger;
// Update file since it already exists
updateFile(req, res, filepath);
}
});
});
function createFile(req, res, filepath) {
try {
let json = JSON.parse(req.body.json);
let output = JSON.stringify([json], null, 4);
fs.mkdir(path.dirname(filepath), function(error) {
if (error) {
if (error.code == 'EEXIST') {
updateFile(req, res, filepath);
} else {
res.sendStatus(500);
console.log('create file error :', error);
}
} else {
fs.writeFile(filepath, output, function(error) {
if (error) {
res.sendStatus(500);
console.log('write file error :', error);
} else {
res.sendStatus(200);
console.log('Data successfully saved');
}
});
}
});
} catch (error) {
res.sendStatus(500);
console.log(error);
}
}
function updateFile(req, res, filepath) {
try {
fs.readFile(filepath, 'utf-8', function(error, data) {
if (error) {
res.sendStatus(500);
console.log('update error:', error);
} else {
try {
let newJSON = JSON.parse(req.body.json);
let jsonArray = JSON.parse(data);
let output;
jsonArray.push(newJSON);
output = JSON.stringify(jsonArray, null, 4);
fs.writeFile(filepath, output, function(error) {
if (error) {
res.sendStatus(500);
console.log(error);
} else {
res.sendStatus(200);
console.log('Data successfully saved');
}
});
} catch (error) {
res.sendStatus(500);
console.log(error);
}
}
});
} catch (error) {
res.sendStatus(500);
console.log(error);
}
}
module.exports = router;

Instead of checking if the file exists, you should try to write with flags wx, which creates a file but fails if it does already exist. That way you won't be subjecting yourself to race conditions. I would also suggest the package mkdirp, which does not emit an error if the directory already exists.
router.post('/', (req, res) => {
if (!(req.body.json && req.body.name && req.body.category)) {
res.sendStatus(400);
return;
}
const dirpath = `public/savedData/${req.body.category}`;
const filepath = `${dirpath}/${req.body.name}.json`;
mkdirp(dirpath, err => {
if (err) {
console.error('mkdirp failed', err);
return res.sendStatus(500);
}
const output = JSON.stringify([JSON.parse(req.body.json)]);
fs.writeFile(filepath, output, { flags: 'wx' }, err => {
if (err) {
console.error('writeFile failed', err);
return res.sendStatus(500);
}
console.log('Data successfully saved');
res.sendStatus(200);
});
);
});
Make sure you sanitize the req.body.name and req.body.category parameters, since you could expose your filesystem to unintentional overwrites.

Thanks to #Iso this is my solution
router.post('/', (req, res) => {
if (!(req.body.json && req.body.name && req.body.category)) {
res.sendStatus(400);
return;
}
const dirpath = 'public/savedData/' + req.body.category;
const filepath = dirpath + '/' + req.body.name + '.json';
mkdirp(dirpath, err => {
if (err) {
console.error('mkdirp failed', err);
return res.sendStatus(500);
}
const output = JSON.stringify([
JSON.parse(req.body.json)
]);
fs.readFile(filepath, 'utf-8', function(error, data) {
if(error) {
fs.writeFile(filepath, output, err => {
if (err) {
console.error('writeFile failed', err);
return res.sendStatus(500);
}
console.log('Data successfully saved');
res.sendStatus(200);
});
} else {
let newJSON = JSON.parse(req.body.json);
let jsonArray = JSON.parse(data);
let output;
jsonArray.push(newJSON);
output = JSON.stringify(jsonArray, null, 4);
fs.writeFile(filepath, output, err => {
if (err) {
console.error('writeFile failed', err);
return res.sendStatus(500);
}
console.log('Data successfully saved');
res.sendStatus(200);
});
}
});
});
});

NodeJS mongo .find is not a function

I'm implementing a little server application with node.js and ran in a problem, where the collection.find() method is not recognized.
Here is my code:
// THIS FUNCTION WORKS CORRECTLY
var find_all_seasons = function (callback) {
var season_collection = db.get().collection('season_collection');
// Find some documents
season_collection.find({}).toArray(function(err, docs) {
assert.equal(err, null);
console.log("Found the following records");
console.log(docs)
callback(docs);
});
};
// HERE I ALWAYS GET THE EXCEPTION
var find_speaker_by_name = function (name, callback) {
var speaker_collection = db.get().collection('speaker_collection').find({"name":name})(function(err, doc) {
assert.equal(err, null);
console.log("Found the following records");
console.log(doc.name)
callback(doc);
});
};
........
app.get('/api/speakers/:name', function (req, res) {
var name = req.params.name;
find_speaker_by_name(name, function (err, result) {
if (err)
res.send(err);
res.json(result);
})
});
Exception:
TypeError: db.get(...).collection(...).find(...) is not a function
at find_speaker_by_name
My DB Connection:
var MongoClient = require('mongodb').MongoClient
var state = {
db: null
};
exports.connect = function(url, done) {
if (state.db) return done();
MongoClient.connect(url, function(err, db) {
if (err) return done(err);
state.db = db;
done()
})
};
exports.get = function() {
return state.db
};
exports.close = function(done) {
if (state.db) {
state.db.close(function(err, result) {
state.db = null
state.mode = null
done(err)
})
}
};