I want to display chatbot and facebook data at the same time. how to display it? because when I try to run in the browser but it does not appear anything. I've tried to look it up on stackoverflow but did not get the right reference
route.js
app.get('/cpanel/facebook', function(req, res) {
if (req.session.user == null) {
res.redirect('/cpanel/login');
} else {
CB.getAllRecords( function(e, chatbot) {
res.render('cpanel/facebook', { udata : req.session.user, chatbot : chatbot });
});
FBM.getAllRecords( function(e, facebook) {
res.render('cpanel/facebook', { udata : req.session.user, facebook : facebook });
});
}
});
facebook.js
var facebook = db.collection('facebook');
exports.addNewFacebook = function(newData, callback) {
facebook.findOne({accesstoken:newData.accesstoken}, function(e, o) {
if (o) {
callback('accesstoken-taken');
} else {
facebook.insert(newData, {safe: true}, callback);
}
});
}
exports.getAllRecords = function(callback) {
facebook.find().toArray(
function(e, res) {
if (e) callback(e)
else callback(null, res)
}
);
}
chatbot.js
var chatbot = db.collection('chatbot');
exports.addNewChatBot = function(newData, callback) {
chatbot.insert(newData, {safe: true}, callback);
}
exports.getAllRecords = function(callback) {
chatbot.find().toArray(
function(e, res) {
if (e) callback(e)
else callback(null, res)
}
);
}
The easier way to manage asynchronous operations in node.js, especially when you have more than one operation that you want to coordinate is to use Promises instead of plain callbacks. And, fortunately, mongodb supports a promise-based interface for all its asynchronous operations now.
So, first change your methods to return a promise instead of taking a callback:
var chatbot = db.collection('chatbot');
exports.getAllRecords = function() {
return chatbot.find().toArray();
}
var facebook = db.collection('facebook');
exports.getAllRecords = function() {
return facebook.find().toArray();
}
Then, you can use those promises with Promise.all() to coordinate:
app.get('/cpanel/facebook', function(req, res) {
if (req.session.user == null) {
res.redirect('/cpanel/login');
} else {
Promise.all([CB.getAllRecords(), FBM.getAllRecords()]).then(results => {
res.render('cpanel/facebook', { udata : req.session.user, chatbot : results[0], facebook: results[1]});
}).catch(err => {
// render some error page here
res.sendStatus(500);
});
}
});
For a call to just a single function that returns a promise, you can use .then():
app.get('/cpanel/facebook', function(req, res) {
if (req.session.user == null) {
res.redirect('/cpanel/login');
} else {
FBM.getAllRecords().then(results => {
res.render('cpanel/facebook', { udata : req.session.user, facebook: results});
}).catch(err => {
// render some error page here
res.sendStatus(500);
});
}
});
Related
I am working on express Api with mongoose to create get Api for my project. I was able to make one get call successfully. But I am not sure how to make api for sorting data by different fields
Model
id,
productName,
costPrice,
soldPrice
router.get("/sellProduct",
(req, res, next) => {
// condition
if(req.query.product){
Product.find({prodName:req.query.product} ).then(data => {
if (data) {
res.status(200).send(data)
}
})
}
// WHAT SHOULD BE THE SORT LOGIC TO SORT BY DIFF FIELD
else if(req.query.sortBy){
Product.find({}).sort().then(data => {
if (data) {
res.status(200).send(data)
}
})
}
else{
Product.find().then(data => {
if (data) {
res.status(200).send(data)
}
})
}
});
I am beigneer and trying my best but any help will be appreciated
You can build the parameters for .find and .sort dynamically:
router.get("/sellProduct", (req, res, next) => {
const findParams = {};
const sortParams = {
lowerCostPrice: { costPrice: 1 },
higherCostPrice: { costPrice: -1 },
lowerSoldPrice: { soldPrice: 1 },
higherSoldPrice: { soldPrice: -1 },
/* add more sort options ... */
}[req.query.sortBy];
if (req.query.product) findParams.prodName = req.query.product
/* add more search options ... */
Product.find(findParams).sort(sortParams).then(data => {
if (data) {
res.status(200).send(data);
} else {
res.status(404);
}
}).catch(err => {
console.log(err);
res.status(500);
});
});
If I understand you question correctly, you can add a switch block and depending on the passed value, sort the products:
router.get('/sellProduct', (req, res, next) => {
let result;
// ...
if (req.query.sortBy) {
switch (req.query.sortBy) {
case 'lowerCostPrice': {
result = await Product.find({}).sort({ price: 'asc' });
break;
}
case 'higherCostPrice': {
result = await Product.find({}).sort({ price: 'desc' });
break;
}
// and so on...
}
}
// ...
res.status(200).send(result);
});
I am working on nodejs and i am using "Express js" framework, I am working on Controller and i am trying to get data from "two model functions" but i am getting message "anonymous", How can i get data from multiple "model functions", Here is my code,
This is my homeController
homeController.index = function (req, res, next) {
// fetching data into 'data variable' from FetchRecords model
homeModel.FetchRecords(function (err, data) {
if (err) {
req.flash('error', 'There was no records.');
} else {
res.render('home/index', { data: data });
}
});
homeModel.getAverage(function (average) {
console.log(average);
// res.render('home/index',{data:average});
});
};
This is my homeMOdel
homeModel.FetchRecords = function (data) {
sql.query('SELECT * FROM rating', function (err, res) {
if (err) {
return data(err, null);
} else {
return data(null, res);
}
});
};
homeModel.getAverage = function (average) {
console.log(average);
sql.query('SELECT avg(value) FROM rating', function (err, res) {
if (err) {
return average(err, null);
} else {
return average(null, res);
}
});
};
Inside homeModel just create 1 function instead of 2 separate. You can combine both MySQL queries into one like this.
const FetchRecordsAndAverage = function (data) {
sql.query('SELECT * FROM rating; SELECT avg(value) FROM rating', function (err, res) {
if (err) {
return data(err, null);
} else {
return data(null, res);
}
});
};
module.exports = {
FetchRecordsAndAverage
}
With this you will get combined data of both queries as arrays inside array.
Result of queries can be accessed as data[0] & data[1].
You should export the function from the home model:
const FetchRecords = function (data) {
sql.query('SELECT * FROM rating', function (err, res) {
if (err) {
return data(err, null);
} else {
return data(null, res);
}
});
};
const getAverage = function (average) {
console.log(average);
sql.query('SELECT avg(value) FROM rating', function (err, res) {
if (err) {
return average(err, null);
} else {
return average(null, res);
}
});
};
module.exports = {
FetchRecords,
getAverage
}
And retrieve them in your application by calling:
const { FetchRecords, getAverage } = require('./path/to/home_model');
I have a PUT request that I'm trying to have hit the backend, but for some reason, it never reaches it. What's odd is the if(req.body.bidderId){} hits no problem, but not the if(req.body.watchingGroup){}
The watching angular service uses identical code to the bidderId so I don't know what's different between the two where only one would reach the endpoint? Whats wrong with the addToWatchList call? I did testing and both console.log statements in code block return the correct value. So the data is ready to be passes, but is never received.
console.log("MADE IT TO LISTINGS BACKEND");
never outputs for watchingGroup scenario
watching.service.ts
addToWatchList(id: string, watchingGroup: string[]) {
const watching: Watching = {
id: id,
watchingGroup: watchingGroup
};
console.log("Here are the values being passed to backend");
console.log(watching.id);
console.log(watching.watchingGroup);
console.log(watching);
return this.http.put(`http://localhost:3000/api/listings/${watching.id}`, watching,
);
}
app.js
app.put("/api/listings/:id", (req, res) => {
console.log("MADE IT TO LISTINGS BACKEND");
if (req.body.biddingGroup) {
console.log("bidding has been received");
Post.findByIdAndUpdate(
{ _id: req.params.id },
{
currentBid: req.body.currentBid,
lastBidTimeStamp: Date.now(),
bidderId: req.body.bidderId,
auctionEndDateTime: req.body.auctionEndDateTime,
biddingGroup: req.body.biddingGroup,
lastBidTimeStamp: req.body.lastBidTimeStamp
},
function(err, docs) {
if (err) res.json(err);
else {
console.log(docs);
}
}
);
}
if (req.body.watchingGroup) {
console.log("watching has been received");
Post.findByIdAndUpdate(
{ _id: req.params.id },
{
watchingGroup: req.body.watchingGroup
},
function(err, docs) {
if (err) res.json(err);
else {
console.log(docs);
}
}
);
}
});
addToWatchList
addToWatchList(
auctionId: string,
watchingGroup: string[]
) {
this.watchItStatus = true;
this.userId = localStorage.getItem("userId: ");
var unique = watchingGroup.filter(function(elem, index, self) {
return index === self.indexOf(elem);
});
this.uniqueResult = unique;
watchingGroup.push(this.userId);
this.watchListService.addToWatchList(auctionId, this.uniqueResult);
}
As i suspected you're not subscribing to it. It's weird but you need to subscribe to it.
this.watchListService.addToWatchList(auctionId, this.uniqueResult).subscribe(
(res) => {
// Handle success response
console.log("SUCCESS");
},
(err) => {
// Handle error response
console.log("ERROR");
}
);
I am trying to replace a string in url . Here is image of it
in this image I want to replace lssplalpha with lssplprod which are in pics array. For that I created an api . Here is a code
apiRoutes.get('/SchoolListing_lssplalpha_Replace',function(req, res) { schoolListModel.find({},function(err,check){
if(err){
return console.log(err);
}
else{
for(var i=0;i<check.length;){
var f=0;
for(var j=0;j<check[i].pics.length;j++){
f++;
var newTitle = check[i].pics[j].replace("lssplalpha","lsslprod");
check[i].pics[j] = newTitle;
console.log("after change",check[i].pics[j]);
check[i].save(function (err) {
if(err) {
console.error('ERROR!');
}
});
}
if(j==check[i].pics.length&&j==f){
i++;
}
}
console.log("i value",i);
console.log("check length",check.length);
if(i==check.length){
return res.json({status:true,message:"Updated Schools"}); }
}
});
});
I am getting success response . When I go and check database nothing changed in db. To know the reason I write log of it. When I see logs it was replacing correctly. But I didn't understand why those are not reflecting in database? Here is an image of log in console
Please help me to come out of this
The issue here is you are running a for loop (synchronous) where you are calling the model.save() operation which is asynchronous and the loop keeps iterating but the results of the async calls come later. The process of saving a database item in an array takes some time and Node.js knows this, so it starts the update and then just moves on trying to update the next item in the array. Once the write operation is complete a callback function is run, but by that point the loop has completed and there is no way to know which items finish in what order.
You could use the Bulk Write API to update your models. This allows you to sends multiple write operations to the MongoDB server in one command. This is faster than sending multiple independent operations (like) if you use create()) because with bulkWrite() there is only one round trip to MongoDB.
The following examples show how you can use the bulkWrite.
Using async/await:
apiRoutes.get('/SchoolListing_lssplalpha_Replace', async (req, res) => {
try {
let ops = [];
const docs = await schoolListModel.find({}).lean().exec();
docs.forEach(doc => {
const pics = doc.pics.map(pic => pic.replace("lssplalpha", "lsslprod"));
ops.push({
"updateOne": {
"filter": { "_id": doc._id },
"update": {
"$set": { pics }
}
}
});
});
const result = await schoolListModel.bulkWrite(ops);
console.log('Bulk update complete.', result);
res.status(200).json({
status: true,
message: "Updated Schools"
});
} catch (err) {
res.status(400).send({
status: false,
message: err
});
}
});
Using Promise API:
const bulkUpdate = (Model, query) => (
new Promise((resolve, reject) => {
let ops = [];
Model.find(query).lean().exec((err, docs) => {
if (err) return reject(err);
docs.forEach(doc => {
const pics = doc.pics.map(pic => (
pic.replace("lssplalpha", "lsslprod")
));
ops.push({
"updateOne": {
"filter": { "_id": doc._id },
"update": {
"$set": { pics }
}
}
});
if (ops.length === 500) {
Model.bulkWrite(ops).then((err, result) => {
if (err) return reject(err);
ops = [];
resolve(result);
});
}
});
if (ops.length > 0) {
Model.bulkWrite(ops).then((err, result) => {
if (err) return reject(err);
resolve(result);
});
}
});
})
);
apiRoutes.get('/SchoolListing_lssplalpha_Replace', (req, res) => {
bulkUpdate(schoolListModel, {}).then(result => {
console.log('Bulk update complete.', result);
res.status(200).json({
status: true,
message: "Updated Schools"
});
}).catch(err => {
res.status(400).send({
status: false,
message: err
});
});
});
You are running asynchronous call model.save() in for loop(synchronous)
To make your for loop synchronous you can use for...of loop which works asynchronous, also you will not need to add multiple checks like you have done in your code.
Try following code, it will work
apiRoutes.get('/SchoolListing_lssplalpha_Replace', function (req, res) {
schoolListModel.find({},function (err, check) {
if (err) {
return console.log(err);
}
else {
for (let checkObj of check) {
let newPicArr=[];
for (let pic of checkObj.pics) {
pic = pic.replace("lssplalpha", "lsslprod");
newPicArr.push(pic);
}
checkObj.pics=newPicArr;
checkObj.save(function (err) {
if (err) {
console.error('ERROR!');
}
});
}
return res.json({ status: true, message: "Updated Schools" });
}
});
});
i'm new!
I can't cope with the problem!
Did I try adding 'return' or not?
thx!
'GET /edit': async (ctx, next) => {
cache.get('user', function (err, result) {
if (err) {
console.log(err);
return;
}
var user = JSON.parse(result);
if (user == null) {
ctx.render('login.html', {
title: '登录'
});
} else {
ctx.render('edit.html');
}
})
// ctx.redirect('/login');
}