Waterline ORM assign the result of find to a variable - sails.js

I want to combine the results of 2 queries and then return them as one, like this:
test: async (req, res) => {
const valOne = TableOne.find({ id: id })
.exec((err, result) => {
if (err) {
res.serverError(err);
}
return result;
});
const valTwo = TableTwo.find({ id: id })
.exec((err, result) => {
if (err) {
res.serverError(err);
}
return result;
});
const data = {
keyOne: valOne,
keyTwo: valTwo,
};
res.json(data);
}
I understand above code won't return because it's async. How can I achieve this?

There is not much info you supply: node version, sails version, etc.
There are several approaches here:
1. Using promises
2. Using callback chaining
3. Using await/async
If you use sails 1.0 and node >= 8, your best bet is to use await/async, so your code should work like that:
test: async (req, res) => {
let valOne, valTwo;
try {
valOne = await TableOne.find({ id: id });
valTwo = await TableTwo.find({ id: id });
} catch (err) {
return res.serverError(err); //or res.badRequest(err);
}
const data = {
keyOne: valOne,
keyTwo: valTwo,
};
res.json(data);
}

Related

how to get callback return value in nestjs

I am going to use vonage for text service.
However, only node.js syntax exists, and the corresponding API is being used.
There is a phenomenon that the callback is executed later when trying to receive the values ​​returned from the callback to check for an error.
How can I solve this part? The code is below.
await vonage.message.sendSms(from, to, text, async (err, responseData) => {
if (err) {
console.log('1');
result.message = err;
} else {
if (responseData.messages[0]['status'] === '0') {
console.log('2');
} else {
console.log('3');
result.error = `Message failed with error: ${responseData.messages[0]['error-text']}`;
}
}
});
console.log(result);
return result;
When an error occurs as a result of executing the above code,
result{error:undefined}
3
Outputs are in order.
From what I can understand the issue is that you are passing a async callback. you could simply just give vonage.message.sendSms() a synchronous callback like so.
const result = {};
vonage.message.sendSms(from, to, text, (err, responseData) => {
if (err) {
console.log('1');
result.message = err;
} else {
if (responseData.messages[0]['status'] === '0') {
console.log('2');
} else {
console.log('3');
result.error = `Message failed with error: ${responseData.messages[0]['error-text']}`;
}
}
});
if you want to use async or promises I would suggest something like this
const sendSMS = (from, to, text) => new Promise( (resolve, reject) => {
vonage.message.sendSms(from, to, text, (err, responseData) => {
if (err) {
reject(err);
} else {
resolve(responseData);
}
});
});
// elsewhere
sendSMS(from, to, text)
.then(...)
.catch(...);

Migrating callbacks to Async

I'm struggling with migrating a HAPI function that verifies a JWT token and then makes a database call using the decoded credentials.
The problem is that jwt.verify uses a callback, but Hapi and Hapi.MySQL2 have both been updated to use async functions
The main function is as follows
exports.LoadAuth = (req, h) => {
let token = req.headers.authorization.split(' ')[1]
VerifyToken(token, async function (err, decoded) {
if (!err) {
let sql = '#SELECT STATEMENT USING decoded.id'
const [data] = await mfjobs.query(sql, decoded.id)
let auids = []
data.forEach(function (ag) {
auids.push(ag.Name)
})
auids = base64(auids.toString())
return auids
} else {
return {message: 'Not Authorised'}
}
})
}
The VerifyToken function is as follows:
VerifyToken = (tok, done) => {
jwt.verify(tok, Buffer.from(secret, 'base64'), function (err, decTok) {
if (err) {
done(err)
} else {
done(null, decTok)
}
})
}
Debugging everything above works up to the point that the data should be returned to the front end. At which point I get an ERROR 500
I know that the issue is with the VerifyToken function as if I omit this and hard code the decoded.id into the query the correct data reaches the front end.
Any pointers?
You can convert your VerifyToken function to Promises.
let VerifyToken = (tok) => {
return new Promise((resolve, reject) => {
jwt.verify(tok, Buffer.from(secret, 'base64'), function (err, decTok) {
if (err) {
reject(err)
} else {
resolve(decTok)
}
})
});
}
Now you have a function that you can use with async await notation and internally checks jwt validation via callbacks.
Then we can slightly modify your controller as follows.
exports.LoadAuth = async (req, h) => {
let token = req.headers.authorization.split(' ')[1];
try {
let decoded = await VerifyToken(token);
let sql = '#SELECT STATEMENT USING decoded.id';
const [data] = await mfjobs.query(sql, decoded.id);
let auids = [];
data.forEach(function (ag) {
auids.push(ag.Name)
});
auids = base64(auids.toString());
return auids
} catch (e) {
return {message: 'Not Authorised'}
}
}
We just converted your handler function to async function, and we already have a VerifyToken function that returns a promise so, we can call it with the await operator.

ES6 Promises in express app not properly resolving data

I'm writing an a async function with ES6 promises, that 1) saves the query parameters for a user 2) fetches data from mongodb using mongoose, 3) manipulates the json into a DSL, 4) and queries another db with it.
mongoose": "^4.7.7"
//myController.js
const myQuery = require('../models/myQuery_model');
require('mongoose').Promise = global.Promise
const uuidV4 = require('uuid/v4');
exports.saveNewQuery = function(req, res, next) {
const rawQuery = req.body;
const queryToStore = new myQuery(rawQuery);
const uid = uuidV4();
const queryToStore.uid = uid
queryToStore.save().then(() => {
fetchQueryFromMongo(uid);
}).then((storedQuery) => {
compileQueryToString(storedQuery);
}).then((queryString) => {
fetchResultsFromOtherDb(queryString);
}).then((results) => {
res.json({ results });
}).catch((error) => {
console.log(error)
})
}
Currently I'm not able to resolve the response from mongodb step 2. Still, the controllter goes on to compileQueryToString rather than catch the error from fetchQueryFromMongo
// fetchQueryFromMongo.js
const myQuery = require('../models/myQuery');
require('mongoose').Promise = global.Promise
module.exports = (uid) => {
return new Promise(
(resolve, reject) => {
myQuery.find({ uid }).then((err, res) => {
if (err) {
reject(err);
}
console.log('response success!')
resolve(res);
});
}
);
};
I'm new to promises so any tips / suggestions would be appreciated!
Make sure to return a value from your then handlers. The code below does this by using the concise body form of arrow functions.
queryToStore.save()
.then(() => fetchQueryFromMongo(uid))
.then(storedQuery => compileQueryToString(storedQuery))
.then(queryString => fetchResultsFromOtherDb(queryString))
.then(results => res.json({ results }))
.catch(console.log);

Using design documents in pouchDB with crypto-pouch

After testing pouchDB for my Ionic project, I tried to encrypt my data with crypto-pouch. But I have a problem with using design documents. I used the following code:
One of my design documents:
var allTypeOne = {
_id: '_design/all_TypeOne',
views: {
'alle_TypeOne': {
map: function (doc) {
if (doc.type === 'type_one') {
emit(doc._id);
}
}.toString()
}
}
};
For init my database:
function initDB() {
_db = new PouchDB('myDatabase', {adapter: 'websql'});
if (!_db.adapter) {
_db = new PouchDB('myDatabase');
}
return _db.crypto(password)
.then(function(){
return _db;
});
// add a design document
_db.put(allTypeOne).then(function (info) {
}).catch(function (err) {
}
}
To get all documents of type_one:
function getAllData {
if (!_data) {
return $q.when(_db.query('all_TypeOne', { include_docs: true}))
.then(function(docs) {
_data = docs.rows.map(function(row) {
return row.doc;
});
_db.changes({ live: true, since: 'now', include_docs: true})
.on('change', onDatabaseChange);
return _data;
});
} else {
return $q.when(_data);
}
}
This code works without using crypto-pouch well, but if I insert the _db.crypto(...) no data is shown in my list. Can anyone help me? Thanks in advance!
I'm guessing that your put is happening before the call to crypto has finished. Remember, javascript is asynchronous. So wait for the crypto call to finish before putting your design doc. And then use a callback to access your database after it's all finished. Something like the following:
function initDB(options) {
_db = new PouchDB('myDatabase', {adapter: 'websql'});
if (!_db.adapter) {
_db = new PouchDB('myDatabase');
}
_db.crypto(password)
.then(function(){
// add a design document
_db.put(allTypeOne).then(function (info) {
options.success(_db);
})
.catch(function (err) { console.error(err); options.error(err)})
.catch(function (err) { console.error(err); options.error(err);})
}
}
initDB({
success:function(db){
db.query....
}
)

How to findAll in mongoosejs?

My code is like that:
SiteModel.find(
{},
function(docs) {
next(null, { data: docs });
}
);
but it never returns anything... but if I specify something in the {} then there is one record. so, how to findall?
Try this code to debug:
SiteModel.find({}, function(err, docs) {
if (!err) {
console.log(docs);
process.exit();
}
else {
throw err;
}
});
The 2017 Node 8.5 way
try {
const results = await SiteModel.find({});
console.log(results);
} catch (err) {
throw err;
}
From the documentation:
let result = SiteModel.find({}, function (err, docs) {});
or using async await you can do like this also:
let result = await SiteModel.find({});
const result = await SiteModel.find() - Without the {} in the .find() function works as well.