Posting a form from Rails programmatically - ruby-on-rails

How would I go about creating and posting a form POST request from inside some Rails code?
The use case I have is that I have received a form request, and I would like to forward this request on to a third party with my parameters intact.
I should add that I want to redirect the user out to the third party with the form too.

From ruby docs for Net::HTTP:
res = Net::HTTP.post_form(URI.parse('http://www.example.com/search.cgi'),
{'q'=>'ruby', 'max'=>'50'})
You could just pass params as the second arg, eg:
Net::HTTP.post_form(URI.parse('http://www.example.com/search.cgi'), params)
redirect_to some_path
Also, don't forget to require the lib:
require 'net/http'
require 'uri'

You're going to have to do this via Javascript, as there is no way of redirecting a POST request (as per the HTTP/1.1 protocol).

You might be able to do it this way:
receive the post form the user
change whatever data you mean to
respond to the request with a form full of hidden fields
automatically post that form to the third party via javascript on dom-loaded
Alternatively:
set the form action to be the third party url
intercept the onsubmit event with js
change whatever data you need, either by simple client-side manipulation of the form
or, post an ajax request to your app to treat the data, and replace the fields you need with from the ajax response
with the data now massaged, let the form go through to the third party

Related

Accessing request parameters in Orbeon form via POST

I want to access some request parameters in an Orbeon form sent via post to this form. I tried to use the XPath expression xxf:get-request-parameter('task_id') within the form, but this only works when the parameter is attached to the url (e.g. orbeon/fr/Activiti/dokumentfreigabe/new?task_id=4711).
Since I do not want to send all parameters in the url (but via POST and SSL), I need a solution to access request parameters in an orbeon form sent as a POST-Parameter.
You can't access parameters sent to the form with a form POST with an XPath function. Could you use an HTTP header to pass this value, instead of a form POST? If it possible, then you could use xxf:get-request-header('your-header').
If the form POST is done by the browser, and not by another server-side app or filter or reverse proxy, then you obviously wouldn't be able to set the header directly from the browser. However, you could continue doing the form POST from the browser, and add a servlet filter that extracts the value, and sets the value of a header, so you can then read it with xxf:get-request-header('your-header').

Can I capture a param but avoid showing it in the url?

I would like to capture the id of an element that is clicked on and then pass that id to the controller, all without showing the id in either the link or the url param, and without having to write custom ajax loading. Anything like that available in rails out of the box?
What are you trying to achieve (what's the end goal)? It sounds like you want to communicate between the client and server without using ajax or encoding params in the user's url.
The usual ways of doing that, with those constraints, would be:
1) Wrap the click target in a form, and set the id to a hidden value. On click, just post the form. This will require a page refresh, but since it's a POST, won't muck up the url.
2) Set the id in a cookie, force a page refresh, read the id on the server and unset it. This will obviously also require a page refresh, but won't encode anything in the url.
3) Use an invisible iFrame to load a url with the param of interest. This won't require a refresh and the url can be anything, since the user will never see it.
If a page refresh/change is fine, the form route is probably best. If you don't want the page to refresh though, an xhr request is clearly the best solution. It's really simple to do, but an iFrame solution would be a hack that probably meets your needs too.
I am assuming you don't want to show the ID to the user but you need the element ID to hit the server.
You could use a custom request header, but that would require an AJAX approach. Here's a sketch with JQuery
$("a.sends_element_id").click(function(e){
e.preventDefault();
$.ajax({
url: $(e.target).attr("href"),
type: "GET",
beforeSend: function(xhr){xhr.setRequestHeader('X-Element-ID', $(e.target).attr("id");},
success: function(result) {
// Do something here to display the page
// Eg. http://stackoverflow.com/questions/824349/modify-the-url-without-reloading-the-page
}
});

Rails take base64

In rails i need to take a base64 string, and use it to generate a picture in rails. Now i'm having trouble, because i need to interact with AJAX calls (im strictly working on the server side, another guy is doing that client work) to send pictures. So far i've been taking requests in my application by having data transferred through the url (in the AJAX requests) but now im not sure if it's possible to transfer such a huge string through the url. How could i take in the data (like how could he pass it to me) to generate a picture.
Note: i've been using paperclip for my application so far, but now uploading through the form is not an option, it needs to be in an AJAX call where data is passed in a single call.
You're right, most browsers limit the length of a URL. The limit on IE8/9 is 2083 characters. Even if your particular browser has a higher limit, many servers limit the URL length as well (apache's default limit is right around 8k). It would be best to submit the image as a POST request with the data in the POST body.
I would use jQuery to POST JSON data to the server. In the controller, if this is set up correctly, you won't have to do a thing to parse the JSON. ActiveSupport will recognize the content type and parse it out into the params hash automatically.
Actually posting the data will depend on which javascript library you're using. Here's an example in jQuery, which you'd probably want to wire up to the onclick event of a submit button. This assumes you have a named route called process_image. This code would go in your view.
$.post(<%= process_image_path %>, { b64_img: "your_base64_image_data" });
In your controller, you can access the posted data with params[:b64_img]. If you want to return something from the controller back to the client, you can do this in the controller:
render :json => #model_object
And change the jquery call to look like this so you can do something with the return value:
$.post(<%= process_image_path %>, { b64_img: "your_base64_image_data" },
function(data) {
// do something with the data returned by the controller
});
Hope this helps. You can read more about the jQuery post call I used here: http://api.jquery.com/jQuery.post/
Dan

rails ajax redirect

Here is my use case
I have a search model with two actions search_set and search_show.
1 - A user loads the home page which contains a search_form, rendered
via a partial (search_form).
2 - User does a search, and the request goes to search_set, the search
is saved and a redirect happens to search_show page which again
renders the search_form with the saved search preferences. This search
form is different than the one if step1, because it's a remote form
being submitted to the same action (search set)
3 - Now the user does another search, and the search form is submitted
via ajax to the search_set action. The search is saved and executed
and now I need to present the result via rjs templates (corresponding
to search_show). I am told that if the request is xhr then I can't
redirect to the search_show action? Is that right? If yes, how do I
handle this?
Here is my controller class
http://pastie.org/993460
Thanks
That's right. Either make the request non-XHR and redirect as normal, or you could try rendering the URL you want to redirect to as text or part of a JSON object which your AJAX request then uses to call document.location.href = [whatever] (but this seems hacky).
Right now what's happening is your XHR request is returning the result of the redirect, and not actually redirecting the page that made the XHR request.

How to post a form with MVC controller?

How do I post a form to an external site using an ASP.NET MVC controller?
EDIT: Ok... I have a view with some data on it. After the user completes the form I need to do a postback with a specified form format to an external site (like for paypal). After I posted the constructed form I need to redirect the action to a new view
You have to do the POST on the server-side..
of which this guy has written a helper class to do Http Post in C# (pastebin-ed). Check it out.
Send the post with the PostSubmitter class and just render your view normally.
Basically, in situation like this one would create a HttpWebRequest, set Method to post and write the post data to the request stream. But the linked code already does that for you in a nice and cozy way.
So no need rewire anything.
You can just manually set the action in the form tag to wherever you want to post to...
edit -
That is to say that you should manually create the form tag..
Instead of:
<% using (Html.Form<Controller>("Action", c => c.Method())) { %>
You should use:
<form action="http://www.someotherwebsite.com/action">
How about sending a redirect to the browser.

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