Hi im getting Parsing error: Unexpected token with no unexpected token if that makes sense. normally it tells you which token is unexpected but not for me.
In my code it says on line x there is an unexpected ) but when i delete that ) the error just moves to the bottom of the page where there is no code and just give the same error but without mentioning what the unexpected token is.
I have looked over google for an answer but its probably somone ; or ) i have missed somewhere so i related to my code but i cant seem to find it.
Here is the code where i get the first unexpected token )
app.put("/index/new_weight", function(req,res){
Exe.findById(req.body.exercise_id, function(err, array){
if (err){
console.log(err);
res.send(err);
}else{
var value = [0];
var oldArray = array.previous;
var newArray = req.body.exe.previous;
for (var i = 0; i < newArray.length; i++){
if (newArray[i] === ""){
value.push(oldArray[i]);
}else{
value.push(newArray[i]);
}
Exe.findByIdAndUpdate(req.body.exercise_id, {$set : {"previous" : value}}, function(err, newArray){
if (err){
console.log(err);
}else{
res.redirect("/index");
}
});
}
};
}); <<<< unexpected token ) apparently...
If i remove said ) the error just moves to the bottom of the page. Same error but doesnt specify what the unexpected token is....
Here is my full code in case the error is coming from above or below. I realize im probably just missing a ) or } somewhere but i cant find.
// REQUIRE REQUIRED FRAMEWORKS AND LIBS
var express = require("express");
var mongoose = require("mongoose");
var bParser = require("body-parser");
var ejs = require("ejs");
var mOverride = require("method-override");
//INITIALIZE EXPRESS, SETUP DB AND CALL LIBS
var app = express();
mongoose.connect("mongodb://localhost/exerciseApp");
app.set("view engine", "ejs");
app.use(express.static(__dirname + "/public"));
app.use(bParser.urlencoded({extended: true}));
app.use(mOverride("_method"));
//DB TEMPLATE
var exerciseSchema = new mongoose.Schema({
user: String,
exercise: [String],
previous: [Number],
latest: [Number]
});
var Exe = mongoose.model("Exe", exerciseSchema);
//**********************TESTING PURPOSES******************************
//CREATE TEST DATA
// Exe.create({
// user: "Template",
// exercise: ["Test"],
// previous: [0],
// latest: [0]
// });
// Exe.create({
// user: "Nathan",
// exercise: ["Bench Press"],
// previous: [35],
// latest: []
// });
// Exe.findOne({name: "Marc"}, function(err, test){
// console.log(test);
// });
//****************************************************
//ROUTES
app.get("/", function(req,res){
res.redirect("/index");
});
app.get("/index", function(req,res){
Exe.find({}, function(err, exercise){
if (err){
res.render("Oops, Somthing went wrong!");
}else{
res.render("index", {exes: exercise});
}
});
});
app.get("/index/new", function(req,res){
res.render("new");
});
app.put("/index", function(req,res){
Exe.update({}, {$push: req.body.exe}, {multi: true}, function(err, numAffected){ //ADDS NEW WORKOUT TO EACH USER
if (err){
console.log(err);
}else{
Exe.update({}, {$push: {"previous" : 0}}, {multi: true}, function(err, numAffected){ //PUSH STARTING VALUE OF 0 INTO PREVIOUS WEIGHT.
if (err){
console.log(err);
}else{
res.redirect("/index");
}
});
}
});
});
app.put("/index/new_weight", function(req,res){
Exe.findById(req.body.exercise_id, function(err, array){
if (err){
console.log(err);
res.send(err);
}else{
var value = [0];
var oldArray = array.previous;
var newArray = req.body.exe.previous;
for (var i = 0; i < newArray.length; i++){
if (newArray[i] === ""){
value.push(oldArray[i]);
}else{
value.push(newArray[i]);
}
Exe.findByIdAndUpdate(req.body.exercise_id, {$set : {"previous" : value}}, function(err, newArray){
if (err){
console.log(err);
}else{
res.redirect("/index");
}
});
}
});
});
app.get("/index/new/user", function(req,res){
res.render("newuser");
});
app.post("/index/new/user", function(req,res){
Exe.findOne({},{},{sort: {create_at: -1}}).lean().exec(function (err, templateSchema){ //.LEAN AND EXEC RETURNS COLLECTION MODEL AS A JS OBJECT.
if (err){
console.log(err);
res.send(err);
} else{
delete templateSchema["_id"];
templateSchema.user = req.body.exe.user;
Exe.create(templateSchema);
res.redirect("/index");
}
});
});
// SETUP SERVER AND LISTEN ON PORT.
app.listen(process.env.PORT, process.env.IP, function(){
console.log("Excercise App Running...");
});
Thanks in advance for any answers!
Here is your code fixed, you miss a } for the for loop and a ) for the Exe.findById function
app.put("/index/new_weight", function (req, res) {
Exe.findById(req.body.exercise_id, function (err, array) {
if (err) {
console.log(err);
res.send(err);
} else {
var value = [0];
var oldArray = array.previous;
var newArray = req.body.exe.previous;
for (var i = 0; i < newArray.length; i++) {
if (newArray[i] === "") {
value.push(oldArray[i]);
} else {
value.push(newArray[i]);
}
Exe.findByIdAndUpdate(req.body.exercise_id, { $set: { "previous": value } }, function (err, newArray) {
if (err) {
console.log(err);
} else {
res.redirect("/index");
}
});
}
}
});
});
Related
To clean up my code, I decided to put all of my schemas and routes into different files in my directory, and require them in my app.js. Each Schema corresponds to each route. For all but one of my routes, I have gotten this to work, but for one specific one, I cannot find out why I am getting it as undefined.
Here is the code I have in my app.js (the main file)
// Schemas
const Transaction = require ("./models/transaction");
User = require ("./models/user");
Ticket = require ("./models/ticket");
Job = require ("./models/job");
Client = require ("./models/client");
// Routes
require("./routes/users")(app);
require("./routes/tickets")(app);
require("./routes/clients")(app);
require("./routes/jobs")(app);
require("./routes/transactions")(app);
All of these work, except for my transaction route.
Here is its schema:
// =======================Transaction Schema "./models/transaction"
var transactionSchema = new mongoose.Schema({
job: String,
client: String,
deposited_by_user: String,
transaction_info:{
amount: mongoose.Decimal128,
method: String,
receipt_number: String,
date: {type: Date}
},
billing_address: {
street: String,
city: String,
state: String,
zip: String
},
notes: String,
date_added: {type: Date, default: Date.now}
});
module.exports = mongoose.model("Transaction", transactionSchema);
And its route:
module.exports = function(app) {
// =======================Transaction "./routes/transactions"
// index
app.get("/transactions", function(req, res){
Transaction.find({}, function(err, transactions){ // It is at this line where it is telling me that "Transaction" is undefined. However, with this code pasted into the app.js exactly the same as it is here, it works fine.
if(err){
console.log("error")
} else {
for (let i = 0; i < transactions.length; i++){
transactions[i]["transaction_info"]["new_amount"] = numberWithCommas(transactions[i]["transaction_info"]["amount"]);
}
res.render("transactions", {transactions: transactions});
}
});
});
// new
app.get("/transactions/add", async function(req, res){
let endCollections = [];
for (let i = 0; i < collections.length; i++){
await collections[i].find({}, function(err, foundCollection){
if (err) {
console.log(err);
} else {
endCollections[i] = foundCollection;
}
});
}
res.render("add_transaction", {users: endCollections[0], clients: endCollections[2], jobs: endCollections[3]});
});
// show
app.get("/transactions/:id", function(req, res){
Transaction.findById(req.params.id, function(err, foundTransaction){
if (err){
console.log(err);
} else {
// Redirect
let price = numberWithCommas(foundTransaction["transaction_info"]["amount"]);
res.render("transaction", {transaction: foundTransaction, price: price});
}
});
});
// edit
app.get("/transactions/:id/edit", function(req, res){
Transaction.findById(req.params.id, async function(err, foundTransaction){
if (err){
console.log("error")
} else {
let endCollections = [];
for (let i = 0; i < collections.length; i++){
await collections[i].find({}, function(err, foundCollection){
if (err) {
console.log(err);
} else {
endCollections[i] = foundCollection;
}
});
}
let deposit_date = foundTransaction["transaction_info"]["date"];
deposit_date = moment(deposit_date).format("MM-DD-YYYY");
res.render("edit_transaction", {transaction: foundTransaction, users: endCollections[0], clients: endCollections[2], jobs: endCollections[3], deposit_date: deposit_date});
}
});
});
// create
app.post("/transactions", function(req, res){
// Create Transaction
Transaction.create(req.body.transaction, function(err, newTransaction){
if (err){
console.log(err)
} else {
// Redirect
res.redirect("/transactions");
}
});
});
// update
app.put("/transactions/:id", function(req, res){
// Update transaction
Transaction.findByIdAndUpdate(req.params.id, req.body.transaction, function(err, updatedTransaction){
if (err){
console.log(err)
} else {
// Redirect
res.redirect("/transactions/" + req.params.id);
}
});
});
// delete
app.delete("/transactions/:id", function(req, res){
// Delete job
Job.findByIdAndRemove(req.params.id, function(err, deletedTransaction){
if (err){
console.log(err)
} else {
// Redirect
res.redirect("/transactions");
}
});
});
}
I do not believe the Schema is the problem because when I paste the Transaction route code directly into my app.js file, character for character, it works fine. However, with it split (and the code stays exactly the same in the transactions.js file) I am getting the error when I load the page that "Transaction is undefined" at the part of my code that starts with Transaction.find
Overall, I cannot understand why when the route is in the app.js file, it works just fine, but when it is in a separate file, the Transaction variable is considered undefined; this is all despite it being modeled exactely the same as my other routes and schemas. Is there something here I am not seeing? Thanks.
1)
Instead of:
app.get("/transactions", function(req, res){
.
.
app.get("/transactions/:id", function(req, res){
Maybe just:
app.get("/", function(req, res){
.
.
app.get("/:id", function(req, res){
and so on?
2)
Transaction.find({}, function(err, transactions){
Instead of {} try ()
Transaction.find((), function(err, transactions){
It looks as you are passing one empty object
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.
I am trying to make a url shortener app using express. I have 2 middle wares for routes /shorten/:url* and /:code respectively. Somehow when I make requests like /shorten/iamarshad.com (requests that are not formatted and will fail my validateUrl method), middleware handling that request gets executed sometimes twice and sometime thrice. Why is this happening ?
Code for route.js:
var express = require("express");
var router = express.Router();
var crypto = require("./crypto");
var styles = "<style>#import url('https://fonts.googleapis.com/css?family=Cormorant+Garamond');" +
"body{background: #fefefe; word-wrap: break-word;}" +
"p {font-size: 30px;color: #b33c66;font-family: 'Cormorant Garamond', monospace;text-align: center;" +
"margin-top: 40vh;font-weight: 500;word-spacing: 2px;}</style>";
function verifyUrl(req, res, next) {
console.log("/shorten middleware called");
req.params.url += req.params[0];
console.log(req.params.url);
if (validateUrl(req.params.url)) {
req.db.collection("counter")
.find({_id: "counter"})
.toArray(function (err, docs) {
if (err) console.error("Error occurred while getting COUNTER document:", err);
req.encodedId = crypto.encode(docs[0].count);
next();
});
}
else {
var elem = "<p>Please enter correct and formatted url!</p>";
res.send(styles + elem);
}
}
function incrementCounter(req, res, next) {
// increasing counter
req.db.collection("counter")
.update(
{
_id: "counter"
},
{
$inc : {
count : 1
}
}
);
next();
}
function insertUrlDocument(req, res, next) {
//inserting new url document
var obj = {original_url: req.params.url, _id: req.encodedId, entry_time: new Date().toUTCString()};
req.db.collection("urls")
.insert(obj, function(err, data) {
if(err) console.error("Error happened while adding new document:", err);
});
next();
}
function sendResponse(req, res) {
var elem = "<p>" + JSON.stringify({'original_url': req.params.url, 'short_url': 'https://shorten-that.herokuapp.com/' + req.encodedId}) + "</p>";
res.send(styles + elem);
}
function validateUrl(url) {
var format = /(http:\/\/|https:\/\/)[a-z0-9\-]+[.]\w+/;
return (format.test(url));
}
router.get("/:code", function(req, res) {
console.log("/:code middleware called with url", req.params.code);
var code = req.params.code.toString();
// searching short-url-id
req.db.collection("urls")
.find({_id: code})
.toArray(function(err, docs) {
if(err) console.error("Error occurred while searching urls:", err);
console.log(docs);
if(docs.length > 0)
res.redirect(docs[0]["original_url"]);
else {
var elem = "<p>Oops, wrong url requested!</p>";
res.send(styles + elem);
}
});
});
// better solution needed
router.get("/shorten/:url*", [verifyUrl, incrementCounter, insertUrlDocument, sendResponse]);
module.exports = router;
Code for server.js:
var express = require("express")
, mongo = require("mongodb").MongoClient
, port = process.env.PORT || 8080
, path = require("path")
, routes = require("./routes")
, favicon = require("serve-favicon");
var app = express();
app.use(favicon(path.join(__dirname, 'public','favicon.png')));
app.use(express.static(path.join(__dirname, "public")));
var url = 'mongodb://localhost:27017/url-shortener';
mongo.connect(url, function(err, db) {
if (err) console.error("Error occurred while connecting to db:", err);
console.log("successfully connected to db.");
app.use(function(req, res, next) {
req.db = db;
next();
});
app.use("/", routes);
});
app.listen(port, function() {
console.log("App running on", port);
});
var express = require('express');
var search = express.Router();
search.get('/', function(req, res, next) {
console.log('1');
dbCall(function(error, result) {
if (error) {
res.status(404).json();
} else {
res.json(result);
}
});
console.log('last');
next();
});
var dbCall = function(callback) {
var couchbase = require('couchbase');
var cluster = new couchbase.Cluster('couchbase://127.0.0.1');
var bucket = cluster.openBucket('default');
var doc;
var ViewQuery = couchbase.ViewQuery;
var query = ViewQuery.from('dev_test', 'allData');
bucket.query(query, function(err, viewResults) {
if (err) {
callback(err, null);
} else {
console.log('inqueryCall');
var results = viewResults;
callback(null, results);
console.log(results);
}
});
};
module.exports = search;
Here's the error that I get is :
Error: Can't set headers after they are sent.
at ServerResponse.OutgoingMessage.setHeader (_http_outgoing.js:346:11)
Can someone please explain the issue here(not just the solution)?
I've added console.log and the issue here is that the couchbase call to async
Remove next() call, that is causing this error. next() is used in middleware to pass the flow to next middleware or endpoint/route
search.get('/', function(req, res, next) {
dbCall(function(error, result) {
if (error) {
res.status(404).json();
} else {
res.json(result);
}
});
});
The error prevents my webpage from being rendered. As mentioned in the title, the error lies in styles.css, when I take this file out, I do not get any errors.
styles.css is included in a separate headers.ejs file which is added in all pages, but there is only one route for which the error is shown(/cats/new). I put up some some logs around my routes and it seems when I enter /cats/new/, I am automatically redirected to a new route (get /cats/:id). I am wondering if this is the cause of the error?
I have attached my routes and the full error message below:
routes:
var express = require('express');
var router = express.Router();
var User = require('../models/user.js');
var Cat = require('../models/cat.js');
var Comment = require('../models/comment.js');
//middleware
function isAuthenticated(req,res,next) {
req.isAuthenticated() ? next() : res.redirect('/login');
}
router.get("/", function(req,res) {
res.redirect("cats");
});
router.get('/cats', function(req,res) {
Cat.find({}, function(err, cats) {
if (err) {
console.log(err);
} else {
res.render('cats', {cats: cats});
}
});
});
router.get('/cats/new', isAuthenticated, function(req,res) {
console.log('went to /cats/new');
res.render('new', {user: req.user});
});
router.post('/cats', isAuthenticated, function(req,res) {
console.log('went to post /cats');
var name = req.body.name;
var image = req.body.url;
var owner = req.user.username
var description = req.body.description;
cat = new Cat({
name: name,
image: image,
owner: owner,
description: description
});
cat.save();
User.findById(req.user._id, function(err, user) {
if (err) {
console.log(err);
} else {
user.cats.push(cat);
user.save();
}
})
res.redirect('cats');
});
router.get('/cats/:id', function(req,res) {
var id = req.params.id;
Cat.findById(id).populate('comments').exec(function(err, cat) {
if (err) {
console.log('entering get /cats/:id');
console.log(err);
} else {
console.log('no errror yet');
console.log(cat.comments);
res.render('show', {cat:cat});
}
});
});
router.post('/cats/:id', isAuthenticated, function(req,res) {
console.log(isAuthenticated);
var id = req.params.id;
Cat.findById(id, function(err, cat) {
console.log('findById running');
if (err) {
console.log(err);
console.log('err finding cat');
res.redirect('/cats');
} else {
console.log('before Comment.create');
Comment.create(req.body.comment, function(err, comment) {
console.log('after Comment.create');
if (err) {
console.log(err);
} else {
console.log('right after 2nd else');
comment.author.id = req.user._id;
console.log(req.user._id);
console.log(req.user.username);
comment.author.username = req.user.username;
comment.cat = id;
comment.save();
console.log('after saving comment');
cat.comments.push(comment);
cat.save();
console.log('saved cat');
User.findById(req.user._id, function(err, user) {
if (err) {
console.log(err);
} else {
user.comments.push(comment);
user.save();
console.log('saved user');
}
});
console.log(comment);
res.redirect("/cats/" + cat._id);
}
});
}
});
});
router.get('/cats/:id/edit', function(req,res) {
var id = req.params.id;
Cat.findById(id, function(err, cat) {
if (err) {
console.log(err);
} else {
res.render('edit.ejs', {cat:cat});
}
});
});
router.put('/cats/:id', function(req,res) {
console.log('beginning /cat/:id');
Cat.findByIdAndUpdate(
req.params.id, req.body.cat, function(err, updatedCat) {
if (err) {
console.log(err);
} else {
console.log('------------ req.body.cat');
console.log(req.body.cat);
console.log('------------ updated cat');
console.log('updated cat');
res.redirect('/cat/' + req.params.id);
console.log('not redirecting?');
}
});
router.delete('/cats/:id',isAuthenticated, function(req,res) {
var id = req.params.id;
console.log('YOU ARE TRYING TO DESTROY A CAT!');
Cat.findByIdAndRemove(id, function(err) {
if (err) {
console.log(err);
res.redirect('/user');
} else {
res.redirect('/user');
}
});
})
});
module.exports = router;
Error:
entering get /cats/:id
{ [CastError: Cast to ObjectId failed for value "styles.css" at path "_id"]
message: 'Cast to ObjectId failed for value "styles.css" at path "_id"',
name: 'CastError',
kind: 'ObjectId',
value: 'styles.css',
path: '_id',
reason: undefined }
It seems you’re including styles.css using a relative path in your template.
So when you navigate to /cats/:id, it tries to load /cats/styles.css.
In order to avoid that, you have to use an absolute path (e.g.: /styles.css or /public/styles.css – I’d recommend serving static files from a dedicated base path).
Go to
<head>
and change
<link rel="stylesheet" href="style.css">
to
<link rel="stylesheet" href="/style.css">