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Nodejs api structure on calling sql helpers inside another helper all called by a controller

I'm studying to create a simple API with mysql. I've understood and implemented the simple structure in which the app call the router, that call the controller, that call the service. But now i'm developing a multiple tag service module and I've realized that I need to call the same sql queries services declared in it. I show you the code for a better understanding:
tag_service.js:
const mysql = require("../../config/database");
module.exports = {
insertTags: async (data, callBack) => {
const connection = await mysql.connection();
let results = '';
const tagsArray = data.tags.map(tag => [data.id_manager,data.cod_table,data.id_record,tag])
try {
//console.log("at insertCallout...");
await connection.query("START TRANSACTION");
results = await connection.query(
`INSERT INTO s_com_tags (id_manager,cod_table,id_record,tag)
VALUES (?,?,?)`,
[tagsArray]
);
await connection.query("COMMIT");
} catch (err) {
await connection.query("ROLLBACK");
//console.log('ROLLBACK at insertCallout', err);
throw err;
} finally {
await connection.release();
return callBack(null, results);
}
},
deleteTags: async (data, callBack) => {
//console.log(data);
let results = '';
const connection = await mysql.connection();
try {
//console.log("at deleteCallouts...");
await connection.query("START TRANSACTION");
results = await connection.query(
`DELETE FROM s_com_tags
WHERE cod_table = ? AND id_record = ? AND tag IN (?)`,
[data.code_table, data.id_record,data.tags]
);
//console.log(res);
await connection.query("COMMIT");
} catch (err) {
await connection.query("ROLLBACK");
//console.log('ROLLBACK at deleteCallouts', err);
throw err;
} finally {
await connection.release();
return callBack(null, Callouts);
}
},
};
controller's structure that will use the service:
module.exports = {
updateLabDesc: async (req, res, next) => {
try {
const body = req.body;
if(!body.internal_code){
updateLabDesc(body.manager, async (err, results) => {
if (err) {
return next(createError.InternalServerError())
}
});
}
updateTags(body, async (err, results) => {
if (err) {
return next(createError.InternalServerError())
}
return res.json({
success: (results ? 1 : 0 ),
message: (results || 0) + " LabDesc inserted successfully"
});
});
} catch (error) {
next(error)
}
},
};
But the update is something like
updateTag function => {
try {
const current_tags = await getTags(req.body);
let newTags = [];
let oldTags = [];
req.body.tags.forEach(tag => {
if(!current_tags.includes(tag))
newTags.push(tag)
});
await insertTags(newTags);
current_tags.tags.forEach(tag => {
if(!req.body.tags.includes(tag))
oldTags.push(tag)
});
await deleteTags(oldTags);
} catch (error) {
next(error)
}
},
Basically, the tag_service has insertTags and deleteTags but I need the updateTags to call these functions as well. The final controller will call insertTags, deleteTags and updateTags. How can I structure these calls?
It is a controller that could call 2 helpers (insertTag and deleteTags) and another helper (updateTags) that call these 2 helpers. Any ideas?

learning and implementing async await

I've been reading about async and await in JS and tried to implement them in my code (which I totally messed up).
Here is my JS.
var express = require('express');
var router = express.Router();
var jsforce = require('jsforce');
const SEC_TOKEN = 'SEC_TOKEN';
const USER_ID = 'USER_ID';
const PASSWORD = 'PWD';
const { default: axios } = require('axios');
router.get("/", async (req, res, next) => {
await initConnect;
await soqlData;
await slackPostTest;
});
initConnect = async () => {
var conn = new jsforce.Connection({
loginUrl: 'https://login.salesforce.com'
});
await conn.login(USER_ID, PASSWORD + SEC_TOKEN, (err, userInfo) => {
if (err)
console.log(err);
else {
console.log(userInfo.Id);
}
});
}
soqlData = async () => {
await conn.query('Select Id, Name from Account LIMIT 1', (err, data) => {
if (err)
console.log(err);
else
return data.records[0];
})
}
slackPostTest = async () => {
await axios.post('SLACK_WEBHOOK', {
"text": "soqlRes"
})
}
module.exports = router;
What I am trying to achieve?
Initialize my connection by passing in SEC_TOKEN, USER_ID, PASSWORD to my initConnect function this will give me a connection (conn).
Use this conn and query my salesforce instance and get some other data.
post some message(currently irrelevant, but will hook up with the above response later) to my slack endpoint.
Also can someone please give me a little detailed explanation of the solution (in terms of async/await)?
Thanks

Assuming everything else about your JsForce API usage was correct (I have no experience with it, so I can't say), here's how to promisify those callback-based APIs and call them.
var express = require("express");
var router = express.Router();
var jsforce = require("jsforce");
const SEC_TOKEN = "SEC_TOKEN";
const USER_ID = "USER_ID";
const PASSWORD = "PWD";
const { default: axios } = require("axios");
router.get("/", async (req, res, next) => {
const { conn, userInfo } = await initConnect();
const data = await soqlData(
conn,
"Select Id, Name from Account LIMIT 1",
);
await slackPostTest(data.records[0]);
});
function initConnect() {
const conn = new jsforce.Connection({
loginUrl: "https://login.salesforce.com",
});
return new Promise((resolve, reject) => {
conn.login(USER_ID, PASSWORD + SEC_TOKEN, (err, userInfo) => {
if (err) return reject(err);
resolve({ conn, userInfo });
});
});
}
function soqlData(conn, query) {
return new Promise((resolve, reject) => {
conn.query(query, (err, data) => {
if (err) return reject(err);
resolve(data);
});
});
}
function slackPostTest(soqlRes) {
return axios.post("SLACK_WEBHOOK", {
text: soqlRes,
});
}
module.exports = router;

How to return value from a function to use it and respone it in router in Nodejs?

I am trying to get result from function getWeather() in Nodejs to respone it to json in one router but I can not get it.
var request = require('request');
var publicIp = require('public-ip');
function getCity (userip){
var url = `https://ipinfo.io/${userip}/json`;
request(url, (err, respone, body)=>{
var data = JSON.parse(body);
var city = data['city'];
return getLocationKey(city);
})
}
function getLocationKey(city){
var url = `http://dataservice.accuweather.com/locations/v1/cities/search?q=${city}&apikey=${API_KEY}`;
request(url, (err, respone, body)=>{
var data = JSON.parse(body);
var key = data[0].Key;
return getWeather(key);
})
}
function getWeather(key){
var url = `http://dataservice.accuweather.com/forecasts/v1/daily/1day/${key}?apikey=${API_KEY}`;
request(url, (err, respone, body)=>{
var weather = JSON.parse(body);
console.log("weather: " + weather);
return weather;
})
}
I have got result from getCity() and getLocationKey(), but when get final result from getWeather() is not successfull.
I console.log weather is Object object. I try to sepate it and call it only, it respone for me weatherDetails as images
router.get('/weather-weather', (req, res)=>{
var city = 'hanoi';
var key = '353412'
var url = `http://dataservice.accuweather.com/forecasts/v1/daily/1day/${key}?apikey=${API_KEY}`;
request(url, (err, respone, body)=>{
var weatherDetails = JSON.parse(body);
res.json(weatherDetails);
})
})
However, I want to call it in this route to respone a json but it fail
router.get('/weather', (req, res)=>{
publicIp.v4()
.then(userip=>{
console.log("userIP: " + userip);
getCity(userip);
})
.catch(err=>{
console.log('Error: '+ err);
})
})
But it failed. I don't know how to return respone result from getWeather() function. How I can get it?

The function getXXX cannot get the "return" inside the callback function.
And you did not call res.json to send the result to the client.
You could pass res to getXXX and use it in this way:
function getCity(userip, res) {
var url = `https://ipinfo.io/${userip}/json`;
request(url, (err, respone, body) => {
var data = JSON.parse(body);
var city = data['city'];
return getLocationKey(city, res);
})
}
function getLocationKey(city, res) {
var url = `http://dataservice.accuweather.com/locations/v1/cities/search?q=${city}&apikey=${API_KEY}`;
request(url, (err, respone, body) => {
var data = JSON.parse(body);
var key = data[0].Key;
return getWeather(key, res);
})
}
function getWeather(key, res) {
var url = `http://dataservice.accuweather.com/forecasts/v1/daily/1day/${key}?apikey=${API_KEY}`;
request(url, (err, respone, body) => {
var weather = JSON.parse(body);
console.log("weather: " + weather);
res.json(weather);
})
}
router.get('/weather', (req, res) => {
publicIp.v4()
.then(userip => {
getCity(userip, res);
})
.catch(err => {
console.log('Error: ' + err);
})
})

Express dosn't get return of other function querying Mongodb [duplicate]

This question already has answers here:
How do I return the response from an asynchronous call?
(41 answers)
Closed 3 years ago.
I'm working in a simple API Key authentication, I just want to verify the given key against the user provied key.
I have a seperate file with the function querying the database, and returning true/false and the user object.
But in my route.js file, the return object is undefined even tough in my auth.js file it isn't.
I tried making the the function in router.get an async function using express-promise-router and making the function an await return var user = await auth.verify(req.params.uid, req.get("token")) but I don't realy know how async works.
router.js
[...]
router.get('/list/:uid', function(req, res) {
var user = auth.verify(req.params.uid, req.get("token"))
console.log("User: " + user) // <-- Undefined
if (user.status) {
res.send("Success")
} else {
res.status(403)
res.json({status: 403, error: "Unkown User / Token"})
}
})
[...]
auth.js
var db = require('./db')
var ObjectId = require('mongodb').ObjectId;
module.exports = {
verify: (uid, key) => {
try {
var collection = db.get().collection('users')
const obj_id = new ObjectId(uid)
const query = { _id: obj_id }
collection.find(query).limit(1).toArray(function(err, user) {
var status = 0;
var usr = {};
if (err) {throw err}else{status=1}
if (user.length <= 0) {throw "NotExistingExc"; status = 0}else{
usr = user[0];
if (key != usr.api) status = 0
}
var returnObj = {
status: status,
user: usr
} /* --> Is {
status: 1,
user: {
_id: d47a2b30b3d2770606942bf0,
name: 'Sh4dow',
groups: [ 0 ],
api: 'YWFiMDI1MGE4NjAyZTg0MWE3N2U0M2I1NzEzZGE1YjE='
}
}
*/
return returnObj;
})
} catch (e) {
console.error(e)
return {
status: 0,
user: {},
error: e
}
}
}
}
db.js (Idk if needed)
var MongoClient = require('mongodb').MongoClient
var state = {
db: null,
}
exports.connect = function(url, done) {
if (state.db) return done()
MongoClient.connect(url, { useNewUrlParser: true }, function(err, db) {
if (err) return done(err)
state.db = db
done()
})
}
exports.get = function() {
return state.db.db("database")
}
exports.close = function(done) {
if (state.db) {
state.db.close(function(err, result) {
state.db = null
state.mode = null
done(err)
})
}
}
I want to have the returnObjin auth.js in the router.get of my route.js file.

Make auth.verify return a Promise which we can then await for it inside router, You can just make the callback async no need for express-promise-router
router.get('/list/:uid', async function(req, res) {
try {
var user = await auth.verify(req.params.uid, req.get("token"))
console.log("User: " + user)
if (user.status) {
res.send("Success")
} else {
res.status(403).json({status: 403, error: "Unkown User / Token"})
}
} catch (e) {
console.error(e)
res.status(/* */).json(/* */)
}
})
auth
module.exports = {
verify: (uid, key) => new Promise((resolve, reject) => {
var collection = db.get().collection('users')
const obj_id = new ObjectId(uid)
const query = { _id: obj_id }
collection.find(query).limit(1).toArray(function(err, user) {
var status = 0;
var usr = {};
if (err) {
reject(err)
return
} else {
status = 1
}
if (user.length <= 0) {
reject(new Error("NotExistingExc"))
return
} else {
usr = user[0]
if (key != usr.api) status = 0
}
var returnObj = {
status: status,
user: usr
}
resolve(returnObj);
})
}
}

In short, the reason you get undefined is because the code in auth.js is asyncronous. But you're really close. The toArray method in MongoDB returns a promise, so you need to make sure you return that promise and then use it in the router correctly.
In auth.js, make sure verify returns a promise - just add return!
return collection.find(query).limit(1).toArray(...)
And then, change your usage of the verify to the async/await you originally tried:
router.get('/list/:uid', async function(req, res) {
var user = await auth.verify(req.params.uid, req.get("token"))
// More code here...
})

ExpressJS Router + Promise not working

I have a problem with Express response and Promise.
My script call a MongoDB Database to get informations from the server. I use Promise to send the result only when my server answered me.
The problem is in my route. I get the response correctly, but the
res.send returns nothing. I can't figure why.
Let's review my code. I've truncated some of the files, as it is not important code.
I have first a server.js file with my router declaration :
let router = express.Router();
app.use('/mongo', MongoRouter);
Then here is my MongoRouter.js file :
import { Router } from 'express';
import { MongoController } from '../Controllers/MongoController';
class MongoRouter {
constructor() {
this.router = Router();
this.controller = new MongoController();
this.routes();
}
routes() {
let obj = this;
this.router.get('/global', (req, res) => {
let promise = obj.controller.globalInfos();
promise.then((value) => {
console.log('Resolve OK. Showing data');
console.log(value);
res.send(value);
}).catch((error) => {
res.status(500).send(error.toString());
});
});
this.router.get('*', (req, res) => {
res.json({
data: 'Invalid route'
});
});
}
}
export default new MongoRouter().router;
And the function globalInfos() from my MongoController :
globalInfos() {
var status = '';
var globalInfos = new Array();
var internalServerReached = 0;
var dbCommand = {'serverStatus': 1};
let obj = this;
return new Promise((resolve, reject) => {
obj.cnxStrings.forEach(element => {
MongoClient.connect(element['cnxString'], (err, db) => {
if (!err) {
if (element['replica'] == true) {
dbCommand = {'replSetGetStatus':1};
}
db.command(dbCommand, (err, results) => {
if (!err) {
status = results;
} else {
status = 'Status unknown';
}
globalInfos[element['name']] = status;
internalServerReached++;
db.close();
if (internalServerReached >= obj.cnxStrings.length) {
console.log('Waiting 3s for the resolve');
setTimeout(() => {
resolve(globalInfos);
},3000);
}
});
} else {
status = 'Unreachable';
}
});
});
});
}
When i go to http://localhost:3000/mongo my function is running, the resolve is called after 3sec, my data are ok in the console (in the .then() callback), but the res.send(..) show an empty array []
Thanks!