I have a variable which contains some data. This variable is in a routeHandler file called content.js. Now i have to pass this variable to a partial called nav.hbs that uses it for some calculation. Can anyone help me out with this? Very new to NodeJS.
PS:- I am using handlebars to design the partial.
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This is just a general question but I can provide an example if necessary. I've been working on a MongoDB/Mongoose, Node.JS, Express, and Handlebars stack app recently and I've ran into some issues with what is being passed from my route to the client side when dealing with Mongoose .find() queries.
I prefer to async await my queries. I have a deeply nested populate query that brings in all the data I need into one object. This is a very simplified breakdown of what I do
async function() { const finalObject = await Model.find({}).populate([*alot more populates*]) }
I pass this into my res.render() route, as so:
res.render('index', { finalObject });
The majority of my experience has been pretty straight forward. I have one issue in a separate stack overflow question about populating the same model twice in one chain (at different levels). I won't address that here.
I decided to do some calculations before passing the object to the route and attach some new values to the properties of the documents. This is where things get weird. I do some calculations and add new properties to documents (these properties are not part of the Schema). When the object is passed to the client-side, those properties I added are available to use (no problem here).
I needed to decode the finalObject into JSON and pass it as JSON as well for an easy use of the data in my client side JavaScript encodedFinalObject = encodeURIComponent(JSON.stringify(finalObject));
I decode it on the client side: clientSideFinalObject = JSON.parse(decodeURIComponent(encodedFinalObject)); and the properties I added are not there!
I'm wondering, how could the new properties I added pass through when I send the object but not pass through when I send the JSON? The decoding is the last thing I do before rendering the page, so it's not a matter of not having my code in the wrong order. I add the properties to the object then decode it.
Some research led me to find out that Model.find({}) does not return a native JavaScript object, but instead a Query. I'm assuming this is a user-defined class data-type that has special behaviors. My assumption is that between the passing from the back-end to the front-end, there is some middle step where the Query does its final processing.
The opposite situation has also occurred. As a solution to this, I decoded the Query finalObject immediately after the Model.find({}) and re-encoded it into a native JavaScript object. After that, I did all my calculations, attached the results as properties to the documents, and sent that new version over as the main finalObject (I still also sent over a separate decoded object for client-side JavaScript use).
This solved the issue of the new properties not being there. They appeared, but this time the decoded then re-encoded finalObject did not have the virtual properties of my Models. The main model has a virtual property that calculates some of it's other properties. It's almost as if that part of the query didn't execute within the .find({}) process. So, when I decoded the finalObject, the virtual properties were never there and were never decoded.
Can anyone explain to me what is going on? Thank you!
I am working on an application that uses MongoDB for data persistence, alongside the mongoose library to allow angularjs to communicate with it. I'm using Postman to test my routes, and that's where the problem comes in.
In MongoDB, I inserted an entry thusly:
db.posts.insert{{id:6, author:"Blah", area:"Sport", body:"bleh", user_id:6, comments:[{author:"foo", body:"bar"}]})
I then queried it through Postman, and it successfully returned the Post, but there was a problem. The comments array had been returned as a strange data type, object Object, and I could not access it from my HTML files.
This is what Postman retrieved:
{"_id":"5536112cffc7bf00b2585d24","id":6,"author":"Blah","area":"Sport","body":"bleh","user_id":6,"comments":["[object Object]"]}]
I want to be able to access the author and body elements of comments independently, or else to be able to get at them from my http files. Does anyone know how I might stop this Object-ification from happening, or failing that, how I might query the data from this new Object?
Thanks.
Instead of passing complete db object we can pass required parameters. below is the example to form the required parameters.
res.json({"author":item.author,"body":item.body});
Here You can find call back function and array conversion from the cursor
I'm building an app in Express. In one of the views a logged in Superadmin is able to view all available clients/user. In this view I am loading a bunch of client data from my MongoDB/Mongoose with a simple:
app.get('/superadmin', function(req, res) {
Client.find({}, '_id company monthly_cost sms_cost', function (err, docs) ...
As you can see above i have choosen only the values that I need from the query. These four are: "_id", "company", "monthly_cost" and "sms_cost"
From the "_id" i can get a "creation date" by using .getTimestamp(), but the Dateobject this function return is bit to complex formated. I need a simpler date, something like: (YYYY-MM-DD). Im thinking of using a small node plugin like dateformat or possibly writing a very simple function that extract the YYYY, MM and DD from the IsoDate object and saving this in a new variable/array
Now to my questions:
Q1) WHERE is actually the right place for this code? I'm currently putting it inside the route handler above... consequently it will follow right below the code above. I'm thinking this is principally the right way according to a MVC pattern. I'm thinking I dont want to put this code in the Jade view template?
Q2) IN WHAT FORM should i save this data and HOW should i pass it along to Jade. Should I somehow add it to the "docs"-data... that is, the data I extract from my DB. Or should I rather put this creationDate in a separate array which i pass to jade side by side with the original DB-data.
I hope my questions are clear enough!
Q1:
If your Mongoose-query is solely dependent on your route /superadmin, this is exactly the right place to put your code. If you are using the same snippet in different routes or functions you might as well wrap it in a function that is accessible to every route in question. But don´t forget to also wrap req, res and other required variables. Have your calculations within your callback and use Jade only for representation of data.
Q2:
What do you mean by "save"? When you are already iterating over every document to do your calculations and transformations, create an extra field creationDate for every document and pass docs as a single parameter to the Jade file afterwards.
Like jQuery we can collect the array of matched DOM element of class 'anything'
with the help of 'find' function
Can i have same functionality in YUI3?
Edit 1:
As i have website source code with the help of php 'file_get_content' function
and i want to find the list of meta tag by YUI3.
Here i used module named
1. io-base : to get the website source code in ajax mode
2. node : to implement functionality over code.
May i know how to parse the responseText to get the list of meta tag?
You can find the collection of all matched elements like this.
YUI().use('node', function(Y){
var myElements = Y.all('.classname');
});
If you are using the io module the user guides may help.
if the format of your response is something like json, you would include the json module and parse the responseText to json and then just treat it as an object. If it's xml that you get back use the responseXML returned via the io call and use the native xml dom functions. (The examples linked on the user guide shows just this type of work)
Also, if you are used to jQuery try the rosettastone site
I writing a node.js application using rethinkdb as a backend.
To retrieve a json value you can use:
r.table('users').get(1).run()
That method call will return the full json document, there is however a method that allows you to specify the attributes to retrieve e.g:
r.table('users').get(1).pick('firstName', 'lastName').run()
I want to make use of this functionality and I have the attributes I want to 'pick' stored in an array. I can't seem to figure out a way to convert this array to a parameter list for the .pick method.
Please advice.
Just use the native apply method to directly pass the arguments array:
r.table('users').get(1).pick.apply(this,yourArray).run()
further reading