Can we use such a chain?
for example, I know urls like abc://wwww.example.com will be handled by a subclass of NSURLProtocol. But it is from a third party library and I do not have the source code to modify the response. So I provide another subclass of NSURLProtocol to handle urls like xyz://www.example.com. I am able to intercept and change urls from abc to xyz. In my own startLoading(), I changed the urls back from xyz to abc and use NSURLSession to send request to abc://www.example.com but got error and looks like the request did not go through the third party NSURPProtocol subclass.
any suggestion?
NSURLProtocol subclasses are only registered globally for NSURLConnection. For NSURLSession, the registration is per-session.
If you want to register an NSURLProtocol in such a way that it would affect third-party libraries, the only way I'm aware of is by swizzling all of the session creation methods on NSURLSession and wrapping them with code that injects your custom protocol into the configuration on the way in.
Related
I am using AFNetworking for my client and server communication. I want to make a wrapper on top of AFNetworking so that I can set common header and extra information for all the HTTP requests. Basically all my HTTP request will go through one layer to AFNetworking. It will make my client server communication easier and I will be able to include any kind of data with all the http request at any point of time. What will be the best way to do it?
As example I want to send token, network status, user info etc.
More specifically:
I want to include some common info with all the request like network info, user info, token. Now its really difficult to change in each and every request. So I want to design in such a way that all the http call will go through one path and I can send anything with AFNetworking HTTP Request without touching all the file.
You should create one separate class that manage all the network related calls. You should subclass NSObject and make a class with different required methods that you need. Import your AFNetwotking in this class and use this class in whole project when needed to make network call!
I want to use a proxy server when opening a url connection with objective-c.But I don't want to use any frameworks other than MKNetworkKit(a third party framework) in my project.Can anyone tell me how to accomplish this?
MKNetworkKit has no special support for HTTP proxies, but, because it uses NSURLConnection and NSURLRequest, you can add proxy support as described in this answer: How to add a proxy to NSURLRequest.
In short:
Implement a custom NSURLProtocol that adds your proxy information to the request
Register your protocol with the URL loading system (+[NSURLProtocol registerClass:])
Use MKNetworkKit as you normally would to load URLs with your custom protocol
Of course, it might be simpler just to use CFNetwork directly.
I'm developing some iOS apps and I'm downloading/uploading data which are very sensitive.
I'm using AFNetworking to do that requests and my question is simple:
I reach only 3 different certificates in all the app, can I custom AFNetworking's layer to accept only these 3 certificates?
The aim of this manipulation will be to avoid "Man To the Middle" attacks and so avoid injection and/or retrieval of any additional information during the HTTP exchanges.
All AFNetworking operations inherit from AFURLConnectionOperation, which defines a block called authenticationChallenge. Setting this block on your operations will define how AFNetworking responds to the NSURLConnectionDelegate method connection:didReceiveAuthenticationChallenge:. Specifically, you will want to inspect challenge.proposedCredential.
If you don't want to set this block on every operation, you could also subclass the operation type you're using (like AFJSONRequestOperation, for example), and override connection:
willSendRequestForAuthenticationChallenge: with the behavior you want.
I'm looking for a way to use NSMutableURLRequest with app level proxyHost/Port settings, essentially a replacement for ASIHTTPRequest lib with proxyHost/proxyPort. I've tried modifying the CFReadStream (from NSURLRequest HTTPBodyStream), but it SIGSEGs when setting the proxy settings. I would rather not have to rewrite my app with CFNetworking, and it looks like AFNetwork lib doesn't include this feature yet either.
Has anyone successfully done this with NSMutableURLRequest?
The real answer appears to be creating a custom NSURLProtocol. Should be a straight forward derivation, and add the appropriate proxyHost/proxyPort to the request (along with any other values such as a customized User Agent string). Then, supposedly, all requests will be routed through this custom protocol (including UIWebView requests..direct or derived).
relevant samples:
https://developer.apple.com/library/ios/samplecode/CustomHTTPProtocol/Introduction/Intro.html#//apple_ref/doc/uid/DTS40013653
http://eng.42go.com/customizing-uiwebview-requests-with-nsurlprotocol/
I'll post more when I have the thing operational.
Things of note with this implementation.
Initially started using CFNetworking as the "wedge" in my custom
NSURLPRotocol, but quickly found I was rewriting the same code that
was in ASIHTTPRequest. So I just implemented the wedge with
ASIHTTPRequest.
The items that are not documented well (or at all), is the
interaction of UIWebView with NSURLProtocol callbacks, vs
NSURLRequest/Conenction with NSURLProtocol. Some Findings:
a) All dependent page resources are loaded automatically by UIWebView
(which we knew), and they all go through NSURLProtocol, so it is an
excellent place to put in code to modify all requests.
b) The UIWebView sets the Referer header. On a redirect, the only
way to get the UIWebView to update it's Referer from the original URL
to the new redirect URL is with the [[self client] URLProtocol:self
wasRedirectedToRequest:redirectRequest
redirectResponse:tmpHttpResponse]; callback.
c) when the above redirect callback is received by UIWebView, it
generates a new NSURLRequest (essentially the one you sent back to
it). So if you have a wedge that likes to do the redirect
internally, you have to cancel the Request that it attempts to make,
in favor of the new one from UIWebView.
You have to be careful with which callbacks you implement from ASIHTTPRequestDelegate. e.g. implementing didReceiveData will disable the built in gzip processing. willRedirectToURL disables most of the built in redirect processing (even if you call [request redirectToURL:newURL]; as recommended in the comments).
As a novice iOS developer, I am trying to understand some concepts related to the callback mechanisms in iOS.
My model makes HTTP requests through NSURLRequest to a backend rest service. The model has several methods which corresponds to the methods in the service. NSURLRequest is based on the delegate pattern, which means that I receive a common callback for all of the service calls. Then, my model has to find out which service call the callback is related to, so that I can send an appropriate update event to the controller. This is awkward since I have to maintain som state in the model to remember which call I made the last time (which is very impractical in the case of concurrency), or interpret the payload in the HTTP response.
I would wish that NSURLRequest would support the target-action pattern, so that each of the requests could decide which callback method to use. Is that possible? Am I missing something here?
If target-action is not available in the framework, what are the best practices to solve this?
The way to do this is to use NSURLRequest with NSURLConnection. If you check out the docs for NSURLConnection, they will tell you that you need to implement the callback methods in the NSURLConnectionDelegate protocol, and will give you details.
That page also points to several examples, with sample code.
You can also check out the URL Loading System Programming Guide at developer.apple.com, which will give you additional information on how these classes are intended to be used.