I started studying node.js, and now I'm trying to do a "Todo-App".
I'm trying to find the best way to transfer data from my database (using mongodb) into my hbs files, so I could display it.
From the server.js -> server to the hbs -> client (correct to me if I'm wrong please, by assuming that server.js is the server of course and the hbs file is the client)
So, I succeeded to do it by passing an array.
but when I'm trying to display in html desing, it just looking bad.
The code:
app.get('/allTasks',(req,res)=>{ //get (go to) the allTasks (hbs file)
Todo.find().then((todos) => {
console.log(todos);
var arrayOfTodos = [];
todos.forEach(function(element){
console.log("\n\n\n\n\n elemnt details: ",element.text + "\n",element.completed+"\n");
arrayOfTodos.push(element.text,element.completed);
});
res.render("allTasks.hbs", {
pageTitle: "Your tasks: ",
todos: arrayOfTodos
});
});
});
The result is:
You can see a picture
As you can see, its just looking bad... cause it just display an array,
an I want to display each task seperately.
Any tips?
Thanks a lot,
Sagiv
Instead of using push just do:
Todo.find().toArray(function(err, result){
arrayOfTodos = result;
})
Once you have your array, the design got nothing to do with mongodb. You will need to learn how to use your render technology. You need to touch your html template, so you should start by posting that.
The problem solved.
I just had to learn how to handle the data in the hbs side.
so the code is: (in hbs)
{{#each todos}}
{{missionNumber}} <br>
{{text}}<br>
completed = {{completed}}<br><br>
{{/each}}
as you can see, the each is a loop , that pass on the todos parameter (my array)
and i just have to display the data in the way i want it to be displayed.
thanks for your help.
Related
This time I'm facing a problem with formatting data from Firebase. This is how structure in my database looks:
I'm getting it from database using this code:
const preObject = document.getElementById('object')
var parametryObject = firebase.database()
.ref('Parametry_powietrza')
.limitToLast(1)
.once('value').then(function(snapshot) {
var listaParametrow = snapshot.val();
console.log(listaParametrow);
preObject.innerText = JSON.stringify(snapshot.val(), null, 3)
});
And on my webpage it looks like:
My question is - how to properly refer to that data to be able to change its appearance using HTML and CSS?
Thank you! :)
It looks like you're trying to access the data inside your JSON object being returned to you from your FireBase RealTime database (RTDB). But the way you've structured your data makes it near impossible for your javascript to iterate through it.
Some pointers I can give you regarding your data in the Realtime Database atm:
1) Datetime is typically stored in what's called Epoch Time. Which is typically the number of seconds since Jan 1, 1970. The number can easily be converted back into text using various javascript time libraries. An easy one to try out is Luxon. You can see epoch time with this online convertor here.
2) Secondly, RTDB supports the creation of unique, sequential, sortable "push-id" whenever you call the .push({ myDataObject }) function. So there's no need to store the date and the time as the "keys" to your object. More info about the push-id here and here. It's really interesting stuff!
3) I hate to be writing this suggestion because it seems like taking a step back before you can take steps forward, but I feel like you would benefit alot on looking at some articles on designing databases and how to sensibly structure your data. Firebase also has a great introduction here. If it's any help, for your data structure, I suggest modifying your data structure to something like below:
{
Parametry_powietrza: {
[firebase_push_id]: {
timestamp: 726354821,
Cisnienie: 1007.78,
Temperatura: 19.23,
Wilgotnosc: 52.00,
},
[firebase_push_id]: {
timestamp: 726354821,
Cisnienie: 1007.78,
Temperatura: 19.23,
Wilgotnosc: 52.00,
}
}
}
That way, when firebase returns your data, you can iterate through the data much more easily and extract the information you need like:
database
.ref('Parametry_powietrza')
.limitToLast(10)
.once('value', snapshot => {
snapshot.forEach(child => {
// do what you need to do with the data
console.log("firebase push id", child.key);
console.log("data", child.val());
})
});
All the best! BTW are you using any javascript frameworks like React or Vue?
I've JSON data
[{"name":"Zohir","id":"151232", "code":"ZO"},{"name":"Tuhhin","id":"151233", "code":"TU"}, .....]
I want to show every single object in different page & also i want to render a single student page based on "code", Like www.mylink.com/student/ZO
I don't know is my question correct or not, I'm new in JavaScript
I tried to show all data in a page from JSON file & i did that, but i can't render a single student page
function getStudent() {
fetch('https://myjesondatas123211.herokuapp.com/v/students')
.then((res) => res.json())
.then((data) => {
let output = '<h2>Students</h2>'
data.forEach(function (student) {
output += `
<div class="col-md-4">
<h4>${student.name}</h4>
<p>${student.id}</p>
<p>${student.code}</p>
</div>
`;
});
document.getElementById('output').innerHTML = output;
})
};
A solution to this problem would be fairly complex to create in plain Javascript.
You would need to have an understanding about single page applications and routers to start tackling this problem.
You might want to look over here or search for another tutorial to get the basics:
https://dev.to/rishavs/making-a-single-page-app-in-ye-good-olde-js-es6-3eng
You want to do a single-page app, which is not simple in plain javascript.
You may want to consider using frameworks for this, such as Angular or React to do this quite easily
They have native routers and allow you to create routes with parameters, and display a component depending on this parameter.
I have an app running in Node.js with Express, and I wanted to dinamically change options on select object with jquery. This is actually not a big problem, but I'm having troubles on using the res.render parameters (which are mongoose documents) in the script tag. I use them without any trouble on the html (jade actually), but in the script tag I get a problem with the ObjectId not being a String.
This is an extract of the code:
On the backend:
router.get("/new", function(req, res){
res.render("session/documentos/new",
{
services: res.locals.services
});
});
On the view
block content
div
h1(class="text-center") New document
form(id="newDoc" action="/session/documentos" method="POST")
div(class="tab") Service:
div(class="form-group")
select(class="form-control" name="svc" id="svc")
option(value="undefined" disabled selected) Choose one
for service in services
option(value=service._id)=service.name
script.
$(document).ready(function() {
var sessLenght = 0;
var selectedSvc = #{services};
$("#svc").change(function(){
console.log("Service changed: " + selectedSvc);
});
});
And this is the error I'm getting:
Console error
And in Sources:
Source error on ObjectId
So I'm being able to use with no troubles the "services" collection of documents, but when trying to use them on the script tag I'm getting problems with the ObjectId element.
I was thinking that one soution would be to convert to string the ObjectId when querying the database, but I think there might be a cleaner solution to that. Which might be the best way to solve the issue?
Any thoughts appreciated! Thanks in advance
Try to change var selectedSvc = #{services};
to var selectedSvc = !{services};
or var selectedSvc = !{JSON.stringify(services)};
I'm using javascript to upload data from webduino, but have trouble with the formatting part.
The part my js pushes data to Firebase is as follows:
myFirebase.push({
messages:{
time:get_time("hms"),
d
}
});
The results in Firebase look like this:
However, to make the database manageable, it has to be like this:
which the "messages" class is above all data.
Please let me know if there is anyway I can adjust my js code to achieve this, thank you!
I think this is what you're trying to do but I'm unsure:
let messagesRef = myFirebase.ref('messages')
messagesRef.push({name: 'blah', text: 'bluh'})
I've solved it,
myFirebase = new Firebase("https://watercup-e06b3.firebaseio.com/messages/");
just add the "/messages" and everything will work!
So thanks to SO I can pass an object from node to the client, but then getting it into a knockout view model is a bit awkward. These are the steps I have so far (I've included links to the relevant lines as they appear in my github project. Thought the context might help.):
Apply JSON.stringify and pass to the jade file
recipeJSON: JSON.stringify(recipe);
Wrap this in a function in a header script that just parses the JSON and returns the result
script
function getRecipeObject() {
var r = '!{recipeJSON}';
return JSON.parse(r);
}
Call this function and pass the result to a view model constructor
self.recipe = ko.observable(new Recipe(getRecipeObject()));
This works but is there a better way?
Question clarification (Edit): I feel step 2 shouldn't be necessary. Is there a way to directly pass the JSON from node to the Recipe() constructor, without the getRecipeObject() acting as an intermediate step? I tried passing recipeJSON in directly like so
self.recipe = ko.observable(JSON.parse('!{recipeJSON}'));
That doesn't work I think because its not a jade template and has no access to the variable.
According to the answer to this question rendering data into scripts is bad practice and I should instead make an XHR call on page load instead.
Edit
I just saw you linked a github repo! So you're already familiar with most of this...you even have an endpoint set up at /recipe/:id/view, so now I'm really confused...what isn't working out for you? Just the last step of deserialization using ko.utils.*?
Sorry about all the exposition -- I thought this was way more rudimentary than it actually was; I hope no offense taken there!
You really don't want to return a script to execute -- instead, treat this as a DTO: an object that just stores data (no behaviors). An example would be:
{
recipeID: 12,
reviewIDs: [42, 12, 55, 31],
rating: 4.2
recipeName: "A super tasty pie!"
}
This object (representation) is a projection -- a simplified version of the full data stored in the database.
The next step is to create an endpoint to access that data on the server. Let's assume you're using Express:
var app = express();
app.get('/recipes/:recipeID', function(req, res) {
var recipeID = req.params.recipeID;
// It would be cool if this existed, huh?
getRecipeAsync(recipeID, function(recipe) {
res.status(200).json(recipe);
});
});
If you send a GET request to your (hypothetical) application (let's say it's https://localhost:8080/recipes/12), you'll get json representing the (admittedly imaginary) recipe with ID 12.
You can accomplish getting the JSON with jQuery (or any other library that makes XHR nice and pretty)
var recipeID = 12;
$.ajax({
url: "/recipes/" + recipeID,
type: "GET"
}).then(function(recipe) {
console.log("Hey! I got the recipe: %O", recipe);
// Note: you might need to use ko.utils.fromJS(recipe) if the returned
// data is JSON that ISN'T deserialized into an object
var recipeObservable = ko.utils.fromJS(recipe);
});
That's about everything you need to know. Obviously, the devil's in the details, but that's basic idea; let me know if that helps!