NSURLProtocol class documentation

Subclasses of NSURLProtocol implement basic handling of URL loading for specific protocols. The NSURLProtocol class itsself is a semi-abstract class giving the essential structure for the subclasses.

You never instantiate NSURLProtocol yourself... it should only ever be done by other classes within the URL loading system.

propertyForKey: inRequest:

+ (id) propertyForKey: (NSString*)key inRequest: (NSURLRequest*)request;

Availability: MacOS-X 10.2.0, Base 1.13.0

Allows subclasses to provide access to proptocol specific properties, returning the property of request stored by the name key or nil if no property had been stored using that key in the request.

registerClass:

+ (BOOL) registerClass: (Class)protocolClass;

Availability: MacOS-X 10.2.0, Base 1.13.0

Registers the specified class so that it can be used to load requests.
When the system is determining which class to use to handle a request it examines them in a most recently registered first order.
The +canInitWithRequest: method is used to determine whether a class may be used to handle a particular request or not. Returns YES if registered (ie the class is an NSURLProtocol subclass), NO otherwise.

setProperty: forKey: inRequest:

+ (void) setProperty: (id)value forKey: (NSString*)key inRequest: (NSMutableURLRequest*)request;

Availability: MacOS-X 10.2.0, Base 1.13.0

Allows subclasses to provide a way to set protocol specific properties, setting the property named key to value in the request.

unregisterClass:

+ (void) unregisterClass: (Class)protocolClass;

Availability: MacOS-X 10.2.0, Base 1.13.0

Unregisters a class which was previously registered using the +registerClass: method.

cachedResponse

- (NSCachedURLResponse*) cachedResponse;

Availability: MacOS-X 10.2.0, Base 1.13.0

Returns the cachedResponse of the receiver.

client

- (id<NSURLProtocolClient>) client;

Availability: MacOS-X 10.2.0, Base 1.13.0

Returns the client associated with the receiver.

initWithRequest: cachedResponse: client:

- (id) initWithRequest: (NSURLRequest*)request cachedResponse: (NSCachedURLResponse*)cachedResponse client: (id<NSURLProtocolClient>)client;

Availability: MacOS-X 10.2.0, Base 1.13.0

Initialises the receiver with request, cachedResponse and client.
The cachedResponse may be the result of a previous load of the request (in which case the protocol may validate and use it).
The client is the object which receives messages about the progress of the load. This is retained by the protocl instance and is released once the last message has been sent to it.

initWithTask: cachedResponse: client:

- (instancetype) initWithTask: (NSURLSessionTask*)task cachedResponse: (NSCachedURLResponse*)cachedResponse client: (id<NSURLProtocolClient>)client;

Availability: MacOS-X 10.2.0, Base 1.13.0

Description forthcoming.

request

- (NSURLRequest*) request;

Availability: MacOS-X 10.2.0, Base 1.13.0

Returns the request handled by the receiver.

task

- (NSURLSessionTask*) task;

Availability: MacOS-X 10.2.0, Base 1.13.0

Returns the task handled by the receiver.

_NSURLProtocolInternal

Warning the underscore at the start of the name of this instance variable indicates that, even though it is not technically private, it is intended for internal use within the package, and you should not use the variable in other code.

Software documentation for the NSURLProtocol(Subclassing) category

NSURLProtocol(Subclassing)

canInitWithRequest:

+ (BOOL) canInitWithRequest: (NSURLRequest*)request;

Availability: MacOS-X 10.2.0, Base 1.13.0

Subclasses must override this method.

This method is called to decide whether a class can deal with the specified request. The abstract class implementation raises an exception.

canonicalRequestForRequest:

+ (NSURLRequest*) canonicalRequestForRequest: (NSURLRequest*)request;

Availability: MacOS-X 10.2.0, Base 1.13.0

Subclasses must override this method.

Returns the 'canonical' version of the request.
The canonical form is used to look up requests in the cache by checking for equality.
The abnstract class implementation simply returns request.