Express.js & Node.js | Rendering template - html

1) Can I render a view with Express without using any template file like jade?
I'm building a real-time chat system for Mobile Devs (cross-platform, so it's a web app) with Node, Express & Socket.io, and the server code core will be build for dispatch messages, user's requests & so on, I don't need to have a view but the result of the functions, because the view is already running on the device.

That's not really rendering, just serving.
You can send a file as answer using res.sendfile :
res.sendfile("pathToYourFile.html");

If you just want to send the results of functions, you can simply send the response without using a template by calling the .end() method (documentation) of the response object that Node passes. An example:
function onRequest( request, response ) {
functionResult = someFunctionYouWantToCall();
response.end( functionResult );
}

Related

How does restangular talk to MySQL database

I am total JS newbie working on a project build in Grail 2.4.4, a web-app. It's a working app, build by a developer whom is not available anymore.
To get it to work locally I had to upgrade it to Grails 3.2.0. I got it almost working in Netbeans. But I got stuck at getting the data from the MySQL database.
The Chrome inspector says:
angular.min.js GET http://localhost:8080/<app>/currency/allCurrencies 404 ()
The controllers are written in Restangular which call the above URL.
What am I missing?
Firstly, Restangular is an Angular library which simplifies and standardizes making calls to a REST backend (which in your case is a Grails app). So, Restangular does not directly retrieve data from your a database, it invokes a web service which (in some cases) may retrieve data from a database.
In your case, Restangular is attempting to retrieve data from the endpoint http://localhost:8080/<app>/currency/allCurrencies but you are getting a 404 response, indicating that there is no endpoint mapped to this URL.
HTTP REST helps you connect to the API easily. Restangular can handle that by sending standard methods [Get, Post, Delete, Put] to the api like what you see.
This mean StudentController > Get()
localhost:2045/api/student
This mean StudentController > Get(Guid id)
localhost:2045/api/student/8ae37cfa-905b-4c71-ad03-bf416d93bdf8
This mean StudentController > POST(Guid id) ... if you send Post method to the API, it will detect it, this work also on put method
localhost:2045/api/student
use this module to get easily rest api.
Http-Rest-Service

MEAN.js $http.get() return index html content instead of json file

I'm doing a web app based on original MEAN.js framework. When I want to request local json test file using $http.get() method in my AngularJS file, it returned my index html content.Is it a routing problem? I didnot change the original mean.js routing code(https://github.com/meanjs/mean), just added a $http.get() method in home.client.controller.js file. Can anyone help me with this? Thanks!
That is most likely happening, because you didn't define an endpoint for that particular GET request in your app.
Everytime you make a request to your server (for example a GET request to /my-request) nodejs/express are configured in MEAN.js so that your server will try to find the endpoint for that request, if it does not find any, that request will be handled by this particular code block (specified in /modules/core/server/routes/core.server.routes.js):
// Define application route
app.route('/*').get(core.renderIndex);
Which will basically render the index view.
I'm not sure if you're using a custom module or not, eitherway, if you want that request to be handled in a different way in MEAN.js, you can specify your endpoint in your custom module routes file (or in core.server.controller.js) like so:
// Define application route
app.route('/my-request').get(core.sendMyJSON);
Be careful, because this route must be placed before the one I mentioned earlier, otherwise your request will still be handled the same way and the index view will be rendered and served again.
Then you will have to create the controller that should be called to handle that request:
exports.sendMyJSON = function (req, res) {
// logic to serve the JSON file
};
This way you should be able to get it done with a few adjustments.
Side note:
I'm not entirely sure but I think if you place your JSON file in the public directory of your app you should be able to directly access it without the need for the extra logic.

Angular.js : CORS HttpInterceptor that transforms $http.get into $http.jsonp request transparently

I've been looking into if it's possible to create a web based version of my Chrome Plugin
now that it's relying completely on Trakt.TV's JSON API.
According to angular's documentation, it's possible to intercept HTTP requests at several levels, one is the HTTP Backend itself (mainly used for testing though) and the other is HTTPInterceptor.get
The basic idea is to wrap calls to Trakt.TV's JSONP api through http://json2jsonp.com/ and have them returned transparently to get around cross site scripting restrictions. This would not only be very useful for my own project, but for a lot of other people daeling with the same issues too (therefore i'll release the module after it's done, but I want to do it properly)
The basics should be simple:
Hook the $http.get request at the right level
Overwrite the original request made
Cancel an optional other request already set up
Hook it through $http.jsonp(http://json2jsonp.com/)
Return the original promise's success/fail when done
Questions:
Has anyone built anything like this yet? (Github searches revealed nothing)
Would you suggest using the HTTPBackend or the HTTPInterceptor?
why can't you just use the jsonp helper function?
httpBakend is a mockup service to fake a backend server is not used on live code. http interceptors would do what you want you just need to attach the callback function name to your request if the url contains what ever name you want to filter and then in the response interceptor you have to pass response to the callback function so the json to be evaluated. be aware that interceptors will inspect every request makde by angular which is not very eficien, unless you are only doing calls to the tv service.
like i said before a better approach is to use $http.jsonp function
https://docs.angularjs.org/api/ng/service/$http#jsonp
a word about interceptors they need to be defined as services and then be passed to HttpProvider during your apps configuration.

How do I feed data into my web-service for a Windows 8 App?

I'm learning how to develop Windows 8 Apps and I've just learned about web-services for the first time using the following tutorial:
Tutorial
Firstly, please accept my apologies if some of my terminology in inaccurate - hopefully you can still get the meaning!
I am using PhP, CSS, JavaScript or the app and MySQL for the database, I am for now developing locally.
I have managed to breakdown the web-service example and get it working with my local database, however in the example I am just entering a URL with parameters attached to the end directly into the web-browser, it is not being generated from anywhere.
How do I now progress to the next step and generate queries directly from my Windows 8 app that will query my database and then be processed by the Web Service?
I have discovered that Visual Studio has han included object that can interpret the results of the web service, however I don't know how to make a call to the database.
Thanks in advance for the support.
To call your web service from windows 8 app, using JS, you can use,
WinJS.xhr( {
url:'http://yourwebserviceurl'
}).then(function (response) {
//response will be the response from your webservice,
})
After you get the response, you can process it to your windows 8 app, either your webservice using XML / JSON based.
If you prefer using jQuery, you can use jquery to request to your web service using this syntax
$.ajax({
url: "your webservice url",
context: document.body
}).done(function() {
//done
});
Cheers
Yusak Setiawan
http://apptivate.ms/apps/1271/mathboard

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.