Cross Domain request for service using SproutCore - ajax

I have been trying to get this resolved, without any success.
I have a webapp residing on my domain, say www.myDomain.com. I need to call a service which is present on another domain, say www.anotherDomain.com/service.do?
I'm using SproutCore's SC.Request.getUrl(www.anotherDomain.com/service.do?) to call that service.
I get an error that says, Origin www.myDomain.com is not allowed by access-control-allow-origin.
When I was in dev stages, and using sc-server, the issue was resolved using proxies. Now that I have deployed the app to an actual server, I replaced all the lines where I had set up the proxy with the actual domain name. I have started getting that error again.
The problem is that I CANNOT MAKE ANY CHANGES to the server on the other domain. All the posts that I have come across state that the other server on the other domain ought to provide access-control-allow-origin header and that it ought to support the OPTIONS verb.
My question is, is it possible for me to connect to that service using SproutCore's SC.Request.getUrl() method?
Additionally, the other posts that I have read mentioned that a simple GET request ought not to be preflighted. Why then are my requests going as OPTION instead of GET?
Thanks a ton in advance! :D

This is not a Sproutcore issue; it's a javascript Same Origin Policy issue.
If you can't modify the production server, you have no option but to develop your own proxy server, and have your proxy hit the real service.
This is effectively replacing sc-server in your production environment.
All this server would do is take the incoming request and pass it along to www.anotherDomain.com/?service.do.
You would need to make sure you passed all parameters, cookies, headers, the http verb, etc....
This is far from ideal, because now errors can occur in more places. Did the real service fail? Did the proxy fail? etc.
If you could modify the other domain, you could
1) deploy your SC app there.
2) put in the CORS headers so you could make cross domain requests

Related

Fastly CDN Heroku url redirecting

I recently added Fastly domain from addons in heroku application. And when fastly was provisioned I got a test url which is as follows:
https://felix-homes-herokuapp-com.global.ssl.fastly.net/
Whenever I click on this url it gets redirected to
https://felix-homes.herokuapp.com for some unknown reason.
Note my nodejs app uses Heroku-SSL-Redirect. Is it because of this?
I have already followed setup guide and asked multiple issues from the support
https://support.fastly.com/hc/en-us/requests/323620?page=1
And nearest question I find to SO is following
Adding Fastly to a Heroku app does not forward to proper url
Clearing browser cache or changing browser did not help me. Can you please try hitting fastly url on your computer and let me know if you are also face same redirect problem?
Yes, very likely the library (Heroku-SSL-Redirect) is the issue.
In the end, you have two separate requests. An encrypted HTTPS/SSL request from the browser. And then an unencrypted request from Fastly to Heroku.
Your node-application and the library only see the unencrypted request and return the redirect.
There are two ways to solve this:
You configure Fastly do do encrypted requests to Heroku as its backend.
Every routing / proxy layer (fastly, but also the Heroku routing layer) typically use the X-Forwarded-Proto HTTP header to tell the backend application that the initial request was already encrypted. So either heroku-ssl-redirect doesn't look at the header, or it did get lost somewhere on way.

Can nginx be configured to allow a path like /api to pass through, and add a header to the request

I am using NGINX as my web server for html/js/css files and my web app UI. It is a single page app that uses AJAX requests to a back end JEtty server. Previously I deployed everything in Jetty and ajax calls worked fine. In separating the back end from the web UI tier, I am now trying to figure out how to configure NGINX to allow AJAX requests to pass through to Jetty. But, I ALSO want to prevent someone from watching network traffic and seeing the ajax calls my app makes, then scripting those themselves. To do this, I believe if I can configure nginx to ADD a custom header to the requests as they pass through (is this even possible?) I could then only accept requests with those headers at my Jetty API level.
If that is possible, is it the right way to handle this so that outsiders can't get in to my back end API? Is there a way they could figure out that my nginx server is adding a header short of breaking in to my server and figuring out the configuration?
If your application calls your api via Ajax on the client there's nothing you can do to stop someone from calling it directly (assuming they otherwise have access to the page). At the end of the day, an Ajax request is just a request made from the client in JS. Now, there are lots of stupid ways to make it more difficult, but, if anyone really wants to call your api directly, they can.
If you're just talking about only allowing access through nginx (or specifically your /api location block), just bind jetty to localhost only.

Azure and CORS Access-Control-Allow-Origin with ajax and php

First I'm not in the web side of our world, so be nice with the backend guy.
A quick background : For a personal need I've developped a google chrome extension. They are basically a webpage loaded in a chrome windows and... yeah that's it. Everything is on the client side (scripts, styles, images, etc...) Only the data are coming from a server through ajax calls. A cron job call a php script every hours to generate two files. One, data.json contains the "latest" datas in a json format. Another one hash.json contain the hash of the data. The client chrome application use local storage. If the remote hash differ from the local one, he simply retrieve the data file from the remote server.
As I have a BizSpark account with Azure my first idea was : Azure Web Site with php for the script, a simple homepage and the generated file and the Azure Scheduler for the jobs.
I've developed everything locally and everything is running fine... but once on the azure plateform I get this error
XMLHttpRequest cannot load http://tso-mc-ws.azurewebsites.net/Core/hash.json. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:23415' is therefore not allowed access.
But what I really can't understand is that I'm able (and you'll be too) to get the file with my browser... So I just don't get it... I've also tried based on some post I've found on SO and other site to manipulate the config, add extra headers, nothing seems to be working...
Any idea ?
But what I really can't understand is that I'm able (and you'll be
too) to get the file with my browser... So I just don't get it
So when you type in http://tso-mc-ws.azurewebsites.net/Core/hash.json in your browser's address bar, it is not a cross-domain request. However when you make an AJAX request from an application which is running in a different domain (http://localhost:23415 in your case), that's a cross-domain request and because CORS is not enabled on your website, you get the error.
As far as enabling CORS is concerned, please take a look at this thread: HTTP OPTIONS request on Azure Websites fails due to CORS. I've never worked with PHP/Azure Websites so I may be wrong with this link but hopefully it should point you in the right direction.
Ok, will perhap's be little troll answer but not my point (I'm .net consultant so... nothing against MS).
I pick a linux azure virtual machine, installed apache and php, configure apache, set some rights and define the header for the CROS and configure a cron in +/- 30minutes... As my goal is to get it running the problem is solved, it's running.

How to Overcome Cross-domain Issues for Ajax Calls to CAS-protected Resources?

What are potential solutions to a redirection problem that occurs when trying to make AJAX calls to a CAS-protected, SSL-encrypted resource located on a server different from the CAS server?
The CAS server is used for authentication and behaves as designed. This issue appears to be ajax-specific.
There is a similar question here, but we cannot use the same domain/server/port for the CAS server and the backend resource.
The JASIG CAS mailing lists mentions using JSESSIONID.
Another possible approach is to modify the CAS Filter to change the expired-ticket default behavior to something more robust.
What design pattern would you use to overcome this issue?
I have 2 suggestions:
can you set up a proxy script on the same domain as the one that holds the JS code? That way the proxy script would query the CAS and return desired results
can you enable JSONP? this type of request is not limited by the security policy (but then anyone could use the service)
I never heard about CAS, but in general: Javascript has some restriction called “same origin policy”. A visible ressource is not automatically visible to Javascript, too. Did you try to access the ressource using a reverse proxy to make it available within the same domain? You could also consider to point your domain onto a separate web server and include both servers as reverse proxies (for Tomacat, JKmounts are to prefer) here.

Cannot make ajax call between servers that differ only in port in HTML5/jQuery/Chrome stack

The parts
I am developing against two Pylons servers and testing locally. One server is on port 5000 and is the called server. The other is on port 7000. The latter creates a cookie that specifies the same domain as used by the former server. Essentially, the first server uses credentials provided by the second server to impersonate the user.
The first server expects to find an auth token (a cookie, really) in its response.environ at run time. When I authenticate on the server on port 7000 and browser to a service on port 5000, the latter server uses the cookie created by the former and the app works.
The fly in the ointment is that the first server creates an HTML5 app that uses an ajax call to the second server, and I cannot get the cookie to be included in the ajax call. I believe that Chrome (the browser we are using/requiring for HTML5 support reasons) refuses to send the cookie for cross domain reasons: going from foo.net:7000 to foo.net:5000 is considered cross domain.
Oh, and the ajax call is through jQuery.
The question
Is there any way to make an ajax call from an HTML5 app created on a port in the same domain to a server in the same domain but a different port?
What I've tried or discard out of hand
I do not believe I can use dynamic script tag insertion because I am making the call from javascript and the HTML is generated on the client at runtime from other javascript. At least, I don't think that is a desirable solution.
I don't believe Access-Control-Allow-* is applicable because I am going from client to server, not the other way.
I've seen this on jQuery and ports in ajax calls. I've seen this, too.
I know about the same-origin policy.
And this does not work.
Agree with Michael that the simplest solution is JSONP. But even in JSONP you need to configure your server such that it supports JSONP. Many Servers deny this to keep their data secure and sound. JSONP expect your server to send data in the format that can be evaluated as the valid JSON. But its not the case in every JSONP Request and response. So, just watch out for that.
The absolutely simplest solution to this is to use JSON/P. I wish there were an easier, softer way to accomplish this, but I certainly haven't found one.

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