Let me tel the scenario where I am stuck, I will try to explain simply rather than telling the actual.
1st : I am on page 1. Where few subjects are there with unique names.
2nd : I will click on one subject, which will call an struts2 action (lets call it ActionA)at back end with the unique subject name as a request parameter(Request type = GET).
3rd : Action A will only redirect to "Tutorial page".
4th : While loading it will make an AJAX call to another Struts2 action (lets call it ActionB), which will return JSON containing tutorials for that Subject.
Problem: As I am calling ActionA first and passing the subject name which is just redirecting the page to some other page. On page load I am calling another action to get the JSON. I am not able to get the request parameter value at ActionB that is the one which is returning JSON.
Note: I am using Struts2-JSON plugin thats why not need two actions, one for redirecting the page another for getting the JSON at page load.
Solution tried: I have tried to get the request parameter value that is the Subject name, putting a hidden field in the Tutorial page. But unable to get the value from inside the Angular JS controller.
Here is the example for a shared Service: http://plnkr.co/edit/P2ItVj20RYCJVjdIaXfY
But you are right if you reload the page this doesn't work. I think your scenario needs tweaking if you want to use angular or any other single page framework for that matter. One purpose of single page applications is to minimize reloads, preferable none. If your action A only returns a template where you then want to input the result of action B, I recommend looking at ngRoute or uiRouter, where you define a template (result of action A) and a controller for that view. This template than replaces a section of your page (ng-view) with the new template. If both are new to you I would recommend looking at uiRouter, it is similar but it gives you a lot more possibilities. Both provide a "resolve" function where you can load your action B before the page is rendered.
Code from plunker
angular.module("app", [])
.controller("MainController", ['SharedService', function(SharedService) {
var vm = this;
//bind to service
vm.service = SharedService;
}]);
Service
angular.module("app")
.factory("SharedService", [function() {
var service = {
id: "test"
}
return service;
}]);
Related
In Sails.js, a route is set up against a controller method which can render a view. For the most part, this is straightforward, i.e. you could set up a GET /users route that points to UserController.find (which is usually set up automatically anyway).
However, say the home page of a blog renders the 10 most recent posts in the main section and a column with a list of authors and categories. The controller method has to fetch posts, authors, and categories before rendering the view and sending it back to the client. Clearly, a method like this doesn't really belong in PostController, AuthorController, or CategoryController.
What's the best thing to do in this situation? Create a controller for rendering views that rely on data from multiple models? Is there a good name for such a controller?
Thanks!
What I would do (this is purely opinion-based) is creating a PageController and create an action for each page you'd want.
For your home page example you can create a home action, get whatever you need and then render it with res.ok() (if everything is fine).
Another option would be to use Sails as a pure API and use HTTP requests (Ajax) or sockets to get your data in JSON. If you want to do so, I'd advise you to use a front end framework such as Angular, Ember, React...
By the way you could also create actions rendering HTML in your existing controllers and create a route to hit them through Ajax requests and just print them in your page. I'd prefer the 2nd solution because it takes full advantage of the Blueprint API (you don't need new controller or action whatsoever).
As Yann pointed out, this answer has to be a little opinionated. It seems that you are using the views system and not building a single page application. For the home page, I would go for an IndexController.js file with a home(req, res) action.
// api/controllers/IndexController.js
module.exports = {
home: function (req, res) {
// Retrieve all the information you need
// Take care about managing the asynchronous calls before rendering the view
return res.view('homepage');
}
};
Declare the route
// config/routes.js
module.exports.routes = {
'get /': 'IndexController.home'
}
Create the view in views/homepage.ejs.
I am new to Django but i am advanced programmer in other frameworks.
What i intend to do:
Press a form button, triggering Javascript that fires a Ajax request which is processed by a Django View (creates a file) that return plain simple JSON data (the name of the file) - and that is appended as a link to a DOM-Element named 'downloads'.
What i achieved so far instead:
Press the button, triggering js that fires a ajax request which is process by a Django view (creates a file) that return the whole page appended as a duplicate to the DOM-Element named 'downloads' (instead of simple JSON data).
here is the extracted code from the corresponding Django view:
context = {
'filename': filename
}
data['filename'] = render_to_string(current_app+'/json_download_link.html', context)
return HttpResponse(json.dumps(data), content_type="application/json")
I tried several variants (like https://stackoverflow.com/a/2428119/850547), with and without RequestContext object; different rendering strats.. i am out of ideas now..
It seems to me that there is NO possibility to make ajax requests without using a template in the response.. :-/ (but i hope i am wrong)
But even then: Why is Django return the main template (with full DOM) that i have NOT passed to the context...
I just want JSON data - not more!
I hope my problem is understandable... if you need more informations let me know and i will add them.
EDIT:
for the upcoming questions - json_download_link.html looks like this:
Download
But i don't even want to use that!
corresponding jquery:
$.post(url, form_data)
.done(function(result){
$('#downloads').append(' Download CSV')
})
I don't understand your question. Of course you can make an Ajax request without using a template. If you don't want to use a template, don't use a template. If you just want to return JSON, then do that.
Without having any details of what's going wrong, I would imagine that your Ajax request is not hitting the view you think it is, but is going to the original full-page view. Try adding some logging in the view to see what's going on.
There is no need to return the full template. You can return parts of template and render/append them at the frontend.
A template can be as small as you want. For example this is a template:
name.html
<p>My name is {{name}}</p>
You can return only this template with json.dumps() and append it on the front end.
What is your json_download_link.html?
assuming example.csv is string
data ={}
data['filename'] = u'example.csv'
return HttpResponse(simplejson.dumps(data), content_type="application/json")
Is this what you are looking for?
In my web page I have a form that is being filled with data after some ajax requests. For example when a user chooses an item from the list, a simple ajax request is sent to the database that the item has been selected (but not confirmed, yet). Then the list on the web page reloads using a simpe ajax request (just the list, not the whole page) to fetch the new item list.
I think this is more or less a classic cart implementation.
However, when the user presses submit (classic form POST submit, not ajax POST for some reasons concerning the implementation) to confirm the whole list, I would like to return to the current page. (Current page varies) Is this possible? I am using django.
Thanks.
You can supply a next GET parameter when submitting the form, similar to django.contrib.auth's login() method:
https://docs.djangoproject.com/en/dev/topics/auth/#django.contrib.auth.views.login:
<form action="/url/to/post/form/?next={{ some_variable }}">
where the variable can simply be the current URL (taken from the request) or a generated URL. In the view processing the form, simply check for a next parameter and redirect appropriately:
from django.shortcuts import redirect
if 'next' in request.GET:
return redirect(request.GET['next'])
You may be able to use the Post/Redirect/Get Design pattern (PRG). For more general information about Post/Redirect/Get please see the following: http://en.wikipedia.org/wiki/Post/Redirect/Get There are some nice process flow diagrams there.
A generic example of a view implementing PRG might look like the following:
# urls.py
urlpatterns = patterns('',
url(r'^/$', views.my_view, name='named_url'),
)
# forms.py
class MyForm(forms.Form):
pass # the form
# views.py
def my_view(request, template_name='template.html'):
""" Example PostRedirectGet
This example uses a request context, but isn't
necessary for the PRG
"""
if request.POST:
form = MyForm(request.POST)
if form.is_valid():
try:
form.save()
# on success, the request is redirected as a GET
return HttpResponseRedirect(reverse('named_url'))
except:
pass # handling can go here
else:
form = MyForm()
return render_to_response(template_name, {
'form':form
}, context_instance=RequestContext(request))
If you need to do something more interesting with the GET, reverse can take args and kwargs. Manipulate the view params, url_pattern, and reverse call to display the results you would like to see.
One additional note is that you don't have to redirect to the same view (as this example does). It could be any named view that you would like to redirect the user to.
current page is a very vague term but i am assuming you want the page that referred you to the form page, this is normally (not always) stored in the HTTP_REFERRER header of the request itself. You could try to fetch that from the request and do a redirect.
I have a tiny application in MVC 3.
In this tiny application, I want my URLs very clear and consistent.
There's just one controller with one action with one parameter.
If no value is provided (that is, / is requested by the browser), then a form is displayed to collect that single value. If a value is provided, a page is rendered.
The only route is this one:
routes.MapRoute(
"Default",
"{account}",
new { controller = "Main", action = "Index", account = UrlParameter.Optional }
);
This all works fine, but the account parameter never appears in the address line as a part of the URL. I can manually type test.com/some_account and it will work, but other than that, the account goes as a post parameter and therefore does not appear. And if I use FormMethods.Get in my form, I get ?account=whatever appended to the URL, which is also not what I want and which goes against my understanding. My understanding was that the MVC framework would try to use parameters set in the route, and only if not found, it would append them after the ?.
I've tried various flavours of setting the routes -- one route with a default parameter, or one route with a required parameter, or two routes (one with a required parameter and one without parameters); I've tried mixing HttpGet/HttpPost in all possible ways; I've tried using single action method with optional parameter string account = null and using two action methods (one with parameter, one without), but I simply can't get the thing appear in the URL.
I have also consulted the Steven Sanderson's book on MVC 3, but on the screenshots there are no parameters either (a details page for Kayak is displayed, but the URL in the address bar is htpp://localhost:XXXX/).
The only thing that definitely works and does what I want is
return RedirectToAction("Index", new { account = "whatever" });
But in order to do it, I have to first check the raw incoming URL and do not redirect if it already contains an account in it, otherwise it is an infinite loop. This seems way too strange and unnecessary.
What is the correct way to make account always appear as a part of the URL?
My understanding was that the MVC framework would try to use
parameters set in the route, and only if not found, it would append
them after the ?
Your understanding is not correct. ASP.NET MVC doesn't append anything. It's the client browser sending the form submission as defined in the HTML specification:
The method attribute of the FORM element specifies the HTTP method used
to send the form to the processing agent. This attribute may take two
values:
get: With the HTTP "get" method, the form data set is appended to the URI specified by the action attribute (with a question-mark ("?")
as separator) and this new URI is sent to the processing agent.
post: With the HTTP "post" method, the form data set is included in the body of the form and sent to the processing agent.
ASP.NET MVC routes are used to parse an incoming client HTTP request and redispatch it to the corresponding controller actions. They are also used by HTML helpers such as Html.ActionLink or Html.BeginForm to generate correct routes. It's just that for your specific scenario where you need to submit a user entered value as part of the url path (not query string) the HTML specification has nothing to offer you.
So, if you want to fight against the HTML specification you will have to use other tools: javascript. So you could use GET method and subscribe to the submit handler of the form and inside it manipulate the url so the value that was appended after the ? satisfy your requirements.
Don't think of this as ASP.NET MVC and routes and stuff. Think of it as a simple HTML page (which is what the browser sees of course) and start tackling the problem from that side. How would you in a simple HTML page achieve this?
I have footer view that's included on all my pages which contains a form. I would like to be able to make use of CI's form validation library to validate the form. Is that possible?
Currently the form posts back to the current page using the PHP_SELF environment variable. I don't want to get it to post to a controller because when validation fails it loads the controller name in the address bar, which is not the desired behaviour.
Any suggestions gratefully received.
Thanks,
Gaz
One way, whilst far from ideal, would be to create a "contact" function in every controller. This could be in the form of a library/helper.
CI doesn't natively let you call one controller from another, although I believe there are extensions that enable this.
Another option would be an AJAX call instead, which would allow you to post to a generic controller, validate etc whilst remaining on the current page.
In this use case, I would definitely go for an AJAX call to a generic controller. This allows you to show errors even before submitting in the origin page.
Another way (slightly more complex), involves posting your form data to a generic controller method, passing it a hidden input containing the current URL.
The generic controller method handling your form can then redirect to the page on which the user submitted the form, passing it the validation errors or a success message using flash session variables: $this->session->set_flashdata('errors',validation_errors()) might do the trick (untested)
The good thing about this is that you can use the generic form-handling method for both the ajax case (suppressing the redirect) and the non-ajax case
AJAX would be best, just like everyone else says.
I would redirect the form to one function in one controller, you could make a controller just for the form itself. Then have a hidden value with the return URL. As far as errors go you could send them back with flashdata.
Just remember to never copy paste code, it a bad practice and guarantees bugs.
//make sure you load the proper model
if ($this->form_validation->run() == FALSE){
// invalid
$redirect = $this->input->post('url');
$this->session->set_flashdata('errors',validation_errors());
redirect($redirect);
} else {
/*
success, do what you want here
*/
redirect('send them where ever');
}