json vs jinja2 templates rendering - json

I'm currently sending data from my flask application to my HTML pages as dicts or list and I use templates rendering to display the values like {{data[0]}}, and I'm wondering is it a bad practice? should I use jsonify instead or it's the same thing?

I'm wondering is it a bad practice?
It's not a bad practice. It's what we called template rendering.
should I use jsonify instead or it's the same thing?
They are not the same thing. jsonify() will return a JSON reponse (Content-Type: application/json), while render_template() reutrn a HTML respone (Content-Type: text/html). The former pass pure data (for machine), the latter show a HTML page (for human).
Normally, you only use jsonify when building a REST API or making AJAX call.

Related

Initialize an Angular page with large json from client?

I am used to creating webapplications with Wicket. There it is possible to generate a HTML page using POST, receiving a large JSON from the client (browser) to generate some charts. This can be done for example with CURL.
In Angular, I could not find a similar approach.
What is the recommended way to render a chart based on the JSON that a browser provides? An URL parameter is not really the way to go as the URL length is limited.
I can think of a work-around wheren I first post the data to some webservice, receive an id, and then pass that id to an URL in Angular, but that seems a lot of work for something simple :)

how to send json file to a restful webservice from html

I recently started learning to create restful web services with spring framework.
all the course is using postman to send requests but I want to send requests from a web page, like creating a table and send firstName and lastName from the HTML file (from the view, .jsp file) and store it in the database.
everywhere I lookt, they all saying the standard file to send to or retrieve from a restful endpoint is JSON, not HTML.
and from what I see #RequestBody only accepts JSON or XML, not HTML inputs.
I tried sending data from HTML(Method = "POST") to a #PostMapping method of my restful web server, to create something and store it in the database but an exception that says "Content-type not supported" was thrown.
I have lots of questions about this, and they all point to the same thing, Not understanding the whole thing.
what's the point of creating restful web service for the back end of a website, when HTML doesn't support put and delete requests and standard file that everyone uses to get requests from the client is JSON, not HTML.
can a web page (HTML) generate it's content to form a JSON file that is being sent back from a restful server?
how can I generate a JSON file from the inputs in HTML file and send it to the restful #PostMapping method?
there are two things that I should mention here,
I don't know much about creating web pages (HTML) I have only been creating very simple HTML files to help me create and test a back end server.
I searched so many questions before I post this one, and none of them helped me.
I will try to answer your questions
First, you need to understand what rest is it is a Representational state transfer (REST) is a software architectural style that defines a set of constraints to be used for creating Web services.(https://en.wikipedia.org/wiki/Representational_state_transfer)
so we follow a set of standards to make things easier.
Now coming to your actual question why JSON and not HTML because these are not only consumed from HTML these are consumed by different apps or services and json is a more lightweight and less verbose format, and it’s easier to read and write as well. In most cases, it’s ideal for data interchange over the internet
and we can use it with front end libraries like react , jquery or vanilla javascript to render the content in HTML from JSON without any changes to the API and also use a Backend web service to use this API.
https://api.jquery.com/jQuery.getJSON/
https://reactjs.org/docs/faq-ajax.html
for the other two questions basically You don't have to generate JSON file to call the rest API from HTML and render the content in HTML Instead you can use front end libraries like Jquery, React, Angular or use vanilla javascript to render content and call the rest API.

what's the utility of json with grails?

I've read many tutorials showing how to use json with grails using templates, but what the utility of doing so? why would I want to show plain json page? ? what the utility of json templates ? like : (from grails official documentation)
model {
Person person
}
json {
name person.name
age person.age
}
since they're not allowing ANY styling ?
Thank you
The reason for this (as pointed out in the comments by dmahapatro) is for use with a REST API.
It makes no sense in the context of displaying this directly to an end-user. However, in the context of a REST API used by another system or by AJAX calls from within a HTML/GSP page it makes a lot of sense.
Since a REST API can be based on HTTP requests made to send/receive JSON data, having the configuration on how a domain class is represented in JSON as a part of the domain class itself helps keep things centralized and tidy. Instead of JSON being manually created or configuration for representing your domain classes in JSON kept somewhere else.

Using HTML Templates at server side

I am working on play framework with SCALA as backend.
Json data is given to the front end from the controller.
I want to add HTML as value of some fields of json.
This HTML will be kept as a template and data will be added in this template at run time.
I think i should put unique names in the HTML template and then these names will be replaced by the data which i want to add at run time. Ultimately, this HTML will be added in the json response.
Is my approach right? If not, what is the best approach to add data in an HTML template,add this template in json response and send this combined response to the front-end for further use?
Is it a good practice to use string replacement to add data in an HTML template?
I think as long as you use Play, you can put your HTML templates into app/views package. Let's say you call your template mytemplate.scala.html
You can parameterize this view as any Play view.
In the place in your code where you generate your JSON response you can then call mytemplate(parameters) to get html generated, Play will do all the work here for you. Then using play.api.libs.json.JSON object's methods and related facilities you can convert this html to JSON.
So in your controller's code you will have something like Ok(JSON.toJson(mytemplate(parameters)))
This is of course a sketch, so you will need to elaborate and try.

Preventing default views with RESTful api in CakePHP

I am following the tutorial in the CakePHP book that explains the basics of setting up a RESTful web service.
So far, I've updated my routes file to the following:
Router::mapResources('stores');
Router::parseExtensions('json');
I have also setup a blank layout in app/layouts/json and the appropriate json views. I am receiving my json output successfully when I navigate to controller/action.json
I am wondering though, without the.json extension it attempts to load the regular view. I am looking to build a pure api with only json output, is there any way to prevent regular render output instead?
You could force a rendering as JSON if you can recognise a JSON request another way. For example, if the Accepts HTTP header contains application/json, you could put this in your controller:
public function beforeFilter(){
if ($this->request->accepts('application/json')) {
$this->RequestHandler->renderAs($this, 'json');
}
parent::beforeFilter();
}
It's CakePHP 2.0 notation, but something similar probably exists for CakePHP 1.2 and 1.3.
You could also detect the request Content-Type instead, or as well, especially if Accepts is not used.
What are you seeing at the moment? If you've used bake Cake may have generated the views for you?
Just delete the views in /app/views/layout and /app/views/controllername
If you are trying to prevent the request from hitting the controller at all then I'm not so sure, you could just update your .htaccess file to only send requests ending in .json to the app or something similar.
here is what i did.
if i know i'm building only json API, i added to my AppController.php following:
public function beforeFilter()
{
if (empty($this->request->params['ext']) || $this->request->params['ext'] != "json")
{
$this->render(FALSE, 'maintenance'); //no view, only layout
$this->response->send();
$this->_stop();
}
}
and in my /app/Layouts/maintenance.ctp
echo __('Invalid extension');
this way all requests without the json extension will end up on the "maintenance" page where you can put any info you want, i'm planning to put there link to API docs.