Request and Response between two projects - angularjs

I'm trying to work on 2 projects. The first one is mainly for client side (AngularJS+MVC) development and second is server side, including web APIs. I want to use web APIs as controllers.
I set the server side project as start-up project. Then set its URL (localhost:..../) as the URL of the controller, then ran the project. After that with the view in the browser, I ran my view, too. (From the client project). The request correctly gets to the API controller from the second project, but I didn't reserve any Response. I guess the problem is the difference between URLs.
What is your opinion? And what should I do, then?

What kind of response are you getting? 200 (OK) status or something else? you might be getting cross orgin request error, if you have not enabled CORS on the web api and you are making the api request from the client side of the Angular project.

Please don't mind my poor English.
Are two projects served on the same domain? If not, there maybe a cross origin request error. You can fix it by adding some headers, like this:
header('Access-Control-Allow-Origin','*');
header('Access-Control-Allow-Methods', 'GET,POST,DELETE,PUT,PATCH');
header('Access-Control-Allow-Headers','Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With');

Related

Unsure what I'm doing wrong with CORS, woocommerce API with a separate React website

I have a locally hosted wordpress installation using woocommerce, and a separate locally hosted react webapp that will be used to manage the products. I'm using the woocommerce-rest-api react plugin to call the end points.
GETs work fine and don't have any issues, however PUT and DELETE I'm having issues with CORS.
I've updated the wordpress htaccess:
and call the endpoint like so:
and this is what I get in dev tools:
Here is the preflight headers and response and then the failing call:
Any ideas what I'm doing wrong or what I've missed?
Your preflight response from (what i assume is the wordpress server) appears to be missing the Access-Control-Allow-Origin header in the response (sent back from the OPTIONS request).
To match your other requests this should be *. However it is not best practice to use * for security reasons and should instead use the domains you want to be able to access this from browsers.

Why is CORS Disabled by Default?

Alright, first of all, I am absolutely aware that we have a bunch of answers on this and there is a plethora of articles on the topic. I just read these answers a second before typing this:
Why is CORS without credentials forbidden?.
Is CORS considered bad practice?
Etc. My particular situation is this - I just set up WebAPI2 for my practice project, the front end for which is running via gulp browser-sync. I have no idea how these ports get picked, but lets say the Web API is running on port http://localhost:1234/ and browser-sync generates the website on http://localhost:4321/. So I hit the API via angular's $http and get the famous CORS error (API controller method does get hit), so I am guessing it's the API returning not allowed. Edit: I fixed this via installing a CORS for Web API package via NuGet (Article Here) before asking this Q, just referencing for anyone who might need it later.
So, I was thinking, if I deployed this, ANY request would get denied, unless I am missing something. Or would it not be denied because of something I don't understand? Is disallowing CORS just a throwback from the MVC days? Or is there some purpose to it with APIs?
Maybe I am just ranting, but this confuses the **** out of me.
CORS is based on the response headers returned from the API. It is not the API that rejects responding to the request, the web browser explicitly disallows handling the response. The API will process the request as normal.
When dealing with anything other than a GET, CORS also requires a "preflight" request to the API first, to ensure subsequent requests are allowed. This amongst sending the headers back is what the Web API nuget package provides.
CORS is off by default for security purposes.

Is a single Cookie Based API for multiple frontends possible from a CORS perspective?

I originally wrote an REST API to work with a previously written mobile app. The mobile programmer requested from me to generate an auth_token on login that he will pass as a header on each request that needed authentication. This API runs at api.example.com.
Later on, I was commissioned to write an AngularJS app that communicates with this API, so I had to use Access-Control-Allow headers on the backend for OPTIONS requests to be CORS compatible CORS so my browser allows the connection (looks like iOS does not look for this headers). This app runs at one.example.com.
Now, I have to write a second AngularJS app that will run at two.example.com and there's a third being planned for the near future at three.example.com.
My problem is that my Access-Control-Allow-Origin header looks like this:
Access-Control-Allow-Origin: http://one.example.com:80
* is not allowed, nor I'm able to set this header to more than one origin. So as far as I can see I have two solutions:
Implement token-based authentication in parallel to the current cookie-based one. I'm thinking on this. This will of course take some time I'm willing to save.
Send the requester a header or param to the API endpoint identifying the app on the OPTIONS request and server-side, produce the CORS headers accordingly. I don't even know if it's possible and this looks nasty for even thinking it.
Any better ideas?
If they have the same origin, example the same domain (example.com) or the same subdomain (1.ex.example.com and 2.ex.example.com) they can share the same cookie. Because cookie is based on the domain itself.

is it possible to intercept the response to an HTTP OPTIONS preflight in AngularJS?

I'm trying to implement a simple interceptor that allows me to display a message along the lines of "cannot contact the server" in my Angular app. However as the API is on a different host I'm dealing with CORS pre-flight OPTIONS requests.
I've found that if the API is unavailable Chrome dev tools shows a 503 on the OPTIONS request but Angular's $http interceptor catches a 404 response to the subsequent GET request. I believe this is because the OPTIONS response did not contain the required CORS headers so the GET is actually never performed.
Is is possible to intercept the OPTIONS response? If all I see is a 404 I can't distinguish "server down" from "no such resource".
You can't intercept this request by design - the browser is "checking up" on you, making sure YOU should be allowed to make the request.
We've used three solutions to work around this:
If the problem is that you're using a development environment like NodeJS, and your domain names aren't matching (that is, if you normally wouldn't need to deal with this in Production) you can use a proxy. The https://github.com/substack/bouncyBounceJS NodeJS Module is an easy to use option. Then your Web service request domain will match the domain your page is on, and the check won't be triggered. (You can also use tricks like this in Production, although it can be easily abused!)
Also for temporary use, you can use something like Fiddler or Charles to manipulate the request by faking the required headers, or tell your browser not to check them (--disable-web-security in Chrome).
If you have this problem in Production, you either need to legitimately fix it (adjust the Web service handler to add the required headers - there are only two), or find a way to make the request in a way that doesn't trigger the check. For instance, if you control both the source and target domains, you can put a script on the target that makes the requests to itself. Run this in an IFRAME, invisibly. Then you can use things like postMessage() to communicate back and forth. Large services like Facebook use "XHR bridges" like this for the same reason.

Backbonejs - CORS error

I have a REST service sitting at http://restservice.net. I am implementing a client for this service in backbone. The client is simply an html file (for bootstrapping the application) and bunch of js files holding my backbonejs code. I am hosting these files on another site http://client.net.
My backbonejs code is calling into http://restservice.net but now allowed due to same origin policy. I have already looked at other SO questions that talk about how I can only talk to http://client.net.
Do I have to redirect every request through http://client.net. I see that as inefficient. What's the point in using a client side MVC framework then? Am I missing something here?
You have two options: JSONP and CORS both of these demand that your http://restservice.net server is setup to suppor the protocols. Forcing backbone to use JSONP simply requires you passing an option to Backbone.sync. One way to do this is like this:
sync: function(method, model, options){
options.dataType = "jsonp";
return Backbone.sync(method, model, options);
}
The problem with JSONP is that you can only make GET requests, so your REST api is effectively read only. To get CORS working you simply need to configure your api server to send back the proper headers . This would pretty liberal:
Access-Control-Allow-Origin: *
Access-Control-Allow-Methods: POST, GET, PUT, DELETE OPTIONS
here is a pretty good run down on CORS. If you set that up, then things will pretty much work as usual.
If you don't have the ability to make changes to the server at http://restservice.net then you have no choice but to proxy all the requests to that service. This is definately inefficient but implementing is probably simpler than you would expect. One thing to consider is a reverse proxy

Resources