Here is my full app.js code.
//jshint esversion:6
const express = require("express");
const bodyParser = require("body-parser");
const mongoose = require("mongoose");
const _ = require("lodash");
const app = express();
app.set('view engine', 'ejs');
app.use(bodyParser.urlencoded({extended: true}));
app.use(express.static("public"));
mongoose.connect("mongodb://localhost:27017/todolistDB", {useNewUrlParser: true});
const itemsSchema = {
name: String
};
const Item = mongoose.model("Item", itemsSchema);
const item1 = new Item({
name: "Welcome to your todolist!"
});
const item2 = new Item({
name: "Hit the + button to add a new item."
});
const item3 = new Item({
name: "<-- Hit this to delete an item."
});
const defaultItems = [item1, item2, item3];
const listSchema = {
name: String,
items: [itemsSchema]
};
const List = mongoose.model("List", listSchema);
app.get("/", function(req, res) {
Item.find({}, function(err, foundItems){
if (foundItems.length === 0) {
Item.insertMany(defaultItems, function(err){
if (err) {
console.log(err);
} else {
console.log("Successfully savevd default items to DB.");
}
});
res.redirect("/");
} else {
res.render("list", {listTitle: "Today", newListItems: foundItems});
}
});
});
app.get("/:customListName", function(req, res){
const customListName = _.capitalize(req.params.customListName);
List.findOne({name: customListName}, function(err, foundList){
if (!err){
if (!foundList){
//Create a new list
const list = new List({
name: customListName,
items: defaultItems
});
list.save();
res.redirect("/" + customListName);
} else {
//Show an existing list
res.render("list", {listTitle: foundList.name, newListItems: foundList.items});
}
}
});
});
app.post("/", function(req, res){
const itemName = req.body.newItem;
const listName = req.body.list;
const item = new Item({
name: itemName
});
if (listName === "Today"){
item.save();
res.redirect("/");
} else {
List.findOne({name: listName}, function(err, foundList){
foundList.items.push(item);
foundList.save();
res.redirect("/" + listName);
});
}
});
app.post("/delete", function(req, res){
const checkedItemId = req.body.checkbox;
const listName = req.body.listName;
if (listName === "Today") {
Item.findByIdAndRemove(checkedItemId, function(err){
if (!err) {
console.log("Successfully deleted checked item.");
res.redirect("/");
}
});
} else {
List.findOneAndUpdate({name: listName}, {$pull: {items: {_id: checkedItemId}}}, function(err, foundList){
if (!err){
res.redirect("/" + listName);
}
});
}
});
app.get("/about", function(req, res){
res.render("about");
});
app.listen(3000, function() {
console.log("Server started on port 3000");
});
Cannot understand where the error is!
The error is:
Model.find() no longer accept a call back.
2
Answers
The error message is self-explanatory: A callback function is a function that you pass as an argument to another function, and that will be called/executed later on after a certain event.
In your specific case, the
find
method doesn’t accept anymore callback functions so you need to removefunction(err, foundItems)...
fromItem.find
:For more info about it, kindly check this link to the docs
You can use an async function instead: