Using class method swizzling to dynamically modify class method values for acceptable status codes and content types

AFNetworking/AFHTTPRequestOperation.h

@@ -28,8 +28,6 @@
  */
 @interface AFHTTPRequestOperation : AFURLConnectionOperation {
 @private
-    NSIndexSet *_acceptableStatusCodes;
-    NSSet *_acceptableContentTypes;
     NSError *_HTTPError;
     dispatch_queue_t _successCallbackQueue;
     dispatch_queue_t _failureCallbackQueue;
@@ -49,25 +47,11 @@
 /// @name Managing And Checking For Acceptable HTTP Responses
 ///----------------------------------------------------------
 
-/**
- Returns an `NSIndexSet` object containing the ranges of acceptable HTTP status codes. When non-`nil`, the operation will set the `error` property to an error in `AFErrorDomain`. See http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
- 
- By default, this is the range 200 to 299, inclusive.
- */
-@property (nonatomic, retain) NSIndexSet *acceptableStatusCodes;
-
 /**
  A Boolean value that corresponds to whether the status code of the response is within the specified set of acceptable status codes. Returns `YES` if `acceptableStatusCodes` is `nil`.
  */
 @property (readonly) BOOL hasAcceptableStatusCode;
 
-/**
- Returns an `NSSet` object containing the acceptable MIME types. When non-`nil`, the operation will set the `error` property to an error in `AFErrorDomain`. See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.17 
- 
- By default, this is `nil`.
- */
-@property (nonatomic, retain) NSSet *acceptableContentTypes;
-
 /**
  A Boolean value that corresponds to whether the MIME type of the response is among the specified set of acceptable content types. Returns `YES` if `acceptableContentTypes` is `nil`.
  */
@@ -83,6 +67,33 @@
  */
 @property (nonatomic) dispatch_queue_t failureCallbackQueue;
 
+///-------------------------------------------------------------
+/// @name Managing Accceptable HTTP Status Codes & Content Types
+///-------------------------------------------------------------
+
+/**
+ Returns an `NSIndexSet` object containing the ranges of acceptable HTTP status codes. When non-`nil`, the operation will set the `error` property to an error in `AFErrorDomain`. See http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
+ 
+ By default, this is the range 200 to 299, inclusive.
+ */
++ (NSIndexSet *)acceptableStatusCodes;
+
+/**
+ 
+ */
++ (void)addAcceptableStatusCodes:(NSIndexSet *)statusCodes;
+
+/**
+ Returns an `NSSet` object containing the acceptable MIME types. When non-`nil`, the operation will set the `error` property to an error in `AFErrorDomain`. See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.17 
+ 
+ By default, this is `nil`.
+ */
++ (NSSet *)acceptableContentTypes;
+
+/**
+ 
+ */
++ (void)addAcceptableContentTypes:(NSSet *)contentTypes;
 
 /**
  A Boolean value determining whether or not the class can process the specified request. For example, `AFJSONRequestOperation` may check to make sure the content type was `application/json` or the URL path extension was `.json`.

AFNetworking/AFHTTPRequestOperation.m

@@ -22,6 +22,15 @@
 
 #import "AFHTTPRequestOperation.h"
 
+#import <objc/runtime.h>
+
+static void AFSwizzleClassMethodWithClassAndSelectorUsingBlock(Class klass, SEL selector, void *block) {
+    Method originalMethod = class_getClassMethod(klass, selector);
+    IMP implementation = imp_implementationWithBlock(block);
+    class_replaceMethod(objc_getMetaClass([NSStringFromClass(klass) cStringUsingEncoding:NSUTF8StringEncoding]), selector, implementation, method_getTypeEncoding(originalMethod));
+    
+}
+
 static NSString * AFStringFromIndexSet(NSIndexSet *indexSet) {
     NSMutableString *string = [NSMutableString string];
 
@@ -59,27 +68,11 @@ static NSString * AFStringFromIndexSet(NSIndexSet *indexSet) {
 @end
 
 @implementation AFHTTPRequestOperation
-@synthesize acceptableStatusCodes = _acceptableStatusCodes;
-@synthesize acceptableContentTypes = _acceptableContentTypes;
 @synthesize HTTPError = _HTTPError;
 @synthesize successCallbackQueue = _successCallbackQueue;
 @synthesize failureCallbackQueue = _failureCallbackQueue;
 
-
-- (id)initWithRequest:(NSURLRequest *)request {
-    self = [super initWithRequest:request];
-    if (!self) {
-        return nil;
-    }
-    
-    self.acceptableStatusCodes = [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(200, 100)];
-    
-    return self;
-}
-
 - (void)dealloc {
-    [_acceptableStatusCodes release];
-    [_acceptableContentTypes release];
     [_HTTPError release];
     
     if (_successCallbackQueue) { 
@@ -103,13 +96,13 @@ static NSString * AFStringFromIndexSet(NSIndexSet *indexSet) {
     if (self.response && !self.HTTPError) {
         if (![self hasAcceptableStatusCode]) {
             NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
-            [userInfo setValue:[NSString stringWithFormat:NSLocalizedString(@"Expected status code in (%@), got %d", nil), AFStringFromIndexSet(self.acceptableStatusCodes), [self.response statusCode]] forKey:NSLocalizedDescriptionKey];
+            [userInfo setValue:[NSString stringWithFormat:NSLocalizedString(@"Expected status code in (%@), got %d", nil), AFStringFromIndexSet([[self class] acceptableStatusCodes]), [self.response statusCode]] forKey:NSLocalizedDescriptionKey];
             [userInfo setValue:[self.request URL] forKey:NSURLErrorFailingURLErrorKey];
             
             self.HTTPError = [[[NSError alloc] initWithDomain:AFNetworkingErrorDomain code:NSURLErrorBadServerResponse userInfo:userInfo] autorelease];
         } else if ([self.responseData length] > 0 && ![self hasAcceptableContentType]) { // Don't invalidate content type if there is no content
             NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
-            [userInfo setValue:[NSString stringWithFormat:NSLocalizedString(@"Expected content type %@, got %@", nil), self.acceptableContentTypes, [self.response MIMEType]] forKey:NSLocalizedDescriptionKey];
+            [userInfo setValue:[NSString stringWithFormat:NSLocalizedString(@"Expected content type %@, got %@", nil), [[self class] acceptableContentTypes], [self.response MIMEType]] forKey:NSLocalizedDescriptionKey];
             [userInfo setValue:[self.request URL] forKey:NSURLErrorFailingURLErrorKey];
             
             self.HTTPError = [[[NSError alloc] initWithDomain:AFNetworkingErrorDomain code:NSURLErrorCannotDecodeContentData userInfo:userInfo] autorelease];
@@ -124,11 +117,11 @@ static NSString * AFStringFromIndexSet(NSIndexSet *indexSet) {
 }
 
 - (BOOL)hasAcceptableStatusCode {
-    return !self.acceptableStatusCodes || [self.acceptableStatusCodes containsIndex:[self.response statusCode]];
+    return ![[self class] acceptableStatusCodes] || [[[self class] acceptableStatusCodes] containsIndex:[self.response statusCode]];
 }
 
 - (BOOL)hasAcceptableContentType {
-    return !self.acceptableContentTypes || [self.acceptableContentTypes containsObject:[self.response MIMEType]];
+    return ![[self class] acceptableContentTypes] || [[[self class] acceptableContentTypes] containsObject:[self.response MIMEType]];
 }
 
 - (void)setSuccessCallbackQueue:(dispatch_queue_t)successCallbackQueue {
@@ -183,6 +176,30 @@ static NSString * AFStringFromIndexSet(NSIndexSet *indexSet) {
 
 #pragma mark - AFHTTPClientOperation
 
++ (NSIndexSet *)acceptableStatusCodes {
+    return [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(200, 100)];
+}
+
++ (void)addAcceptableStatusCodes:(NSIndexSet *)statusCodes {
+    NSMutableIndexSet *mutableStatusCodes = [[[NSMutableIndexSet alloc] initWithIndexSet:[self acceptableStatusCodes]] autorelease];
+    [mutableStatusCodes addIndexes:statusCodes];
+    AFSwizzleClassMethodWithClassAndSelectorUsingBlock([self class], @selector(acceptableStatusCodes), ^(id _self) {
+        return mutableStatusCodes;
+    });
+}
+
++ (NSSet *)acceptableContentTypes {
+    return nil;
+}
+
++ (void)addAcceptableContentTypes:(NSSet *)contentTypes {
+    NSMutableSet *mutableContentTypes = [[[NSMutableSet alloc] initWithSet:[self acceptableContentTypes] copyItems:YES] autorelease];
+    [mutableContentTypes unionSet:contentTypes];
+    AFSwizzleClassMethodWithClassAndSelectorUsingBlock([self class], @selector(acceptableContentTypes), ^(id _self) {
+        return mutableContentTypes;
+    });
+}
+
 + (BOOL)canProcessRequest:(NSURLRequest *)request {
     return YES;
 }

AFNetworking/AFImageRequestOperation.m

@@ -38,7 +38,6 @@ static dispatch_queue_t image_request_operation_processing_queue() {
 @property (readwrite, nonatomic, retain) NSImage *responseImage;
 #endif
 
-+ (NSSet *)defaultAcceptableContentTypes;
 + (NSSet *)defaultAcceptablePathExtensions;
 @end
 
@@ -126,7 +125,7 @@ static dispatch_queue_t image_request_operation_processing_queue() {
 }
 #endif
 
-+ (NSSet *)defaultAcceptableContentTypes {
++ (NSSet *)acceptableContentTypes {
     return [NSSet setWithObjects:@"image/tiff", @"image/jpeg", @"image/gif", @"image/png", @"image/ico", @"image/x-icon", @"image/bmp", @"image/x-bmp", @"image/x-xbitmap", @"image/x-win-bitmap", nil];
 }
 
@@ -139,9 +138,7 @@ static dispatch_queue_t image_request_operation_processing_queue() {
     if (!self) {
         return nil;
     }
-    
-    self.acceptableContentTypes = [[self class] defaultAcceptableContentTypes];
-    
+        
 #if __IPHONE_OS_VERSION_MIN_REQUIRED
     self.imageScale = [[UIScreen mainScreen] scale];
 #endif
@@ -193,7 +190,7 @@ static dispatch_queue_t image_request_operation_processing_queue() {
 #pragma mark - AFHTTPClientOperation
 
 + (BOOL)canProcessRequest:(NSURLRequest *)request {
-    return [[self defaultAcceptableContentTypes] containsObject:[request valueForHTTPHeaderField:@"Accept"]] || [[self defaultAcceptablePathExtensions] containsObject:[[request URL] pathExtension]];
+    return [[[self class] acceptableContentTypes] containsObject:[request valueForHTTPHeaderField:@"Accept"]] || [[self defaultAcceptablePathExtensions] containsObject:[[request URL] pathExtension]];
 }
 
 #if __IPHONE_OS_VERSION_MIN_REQUIRED

AFNetworking/AFJSONRequestOperation.m

@@ -36,7 +36,6 @@ static dispatch_queue_t json_request_operation_processing_queue() {
 @property (readwrite, nonatomic, retain) id responseJSON;
 @property (readwrite, nonatomic, retain) NSError *JSONError;
 
-+ (NSSet *)defaultAcceptableContentTypes;
 + (NSSet *)defaultAcceptablePathExtensions;
 @end
 
@@ -62,7 +61,7 @@ static dispatch_queue_t json_request_operation_processing_queue() {
     return requestOperation;
 }
 
-+ (NSSet *)defaultAcceptableContentTypes {
++ (NSSet *)acceptableContentTypes {
     return [NSSet setWithObjects:@"application/json", @"text/json", @"text/javascript", nil];
 }
 
@@ -71,18 +70,7 @@ static dispatch_queue_t json_request_operation_processing_queue() {
 }
 
 + (BOOL)canProcessRequest:(NSURLRequest *)request {
-    return [[self defaultAcceptableContentTypes] containsObject:[request valueForHTTPHeaderField:@"Accept"]] || [[self defaultAcceptablePathExtensions] containsObject:[[request URL] pathExtension]];
-}
-
-- (id)initWithRequest:(NSURLRequest *)urlRequest {
-    self = [super initWithRequest:urlRequest];
-    if (!self) {
-        return nil;
-    }
-    
-    self.acceptableContentTypes = [[self class] defaultAcceptableContentTypes];
-    
-    return self;
+    return [[self acceptableContentTypes] containsObject:[request valueForHTTPHeaderField:@"Accept"]] || [[self defaultAcceptablePathExtensions] containsObject:[[request URL] pathExtension]];
 }
 
 - (void)dealloc {

AFNetworking/AFPropertyListRequestOperation.m

@@ -36,7 +36,6 @@ static dispatch_queue_t property_list_request_operation_processing_queue() {
 @property (readwrite, nonatomic, assign) NSPropertyListFormat propertyListFormat;
 @property (readwrite, nonatomic, retain) NSError *propertyListError;
 
-+ (NSSet *)defaultAcceptableContentTypes;
 + (NSSet *)defaultAcceptablePathExtensions;
 @end
 
@@ -64,7 +63,7 @@ static dispatch_queue_t property_list_request_operation_processing_queue() {
     return requestOperation;
 }
 
-+ (NSSet *)defaultAcceptableContentTypes {
++ (NSSet *)acceptableContentTypes {
     return [NSSet setWithObjects:@"application/x-plist", nil];
 }
 
@@ -77,9 +76,7 @@ static dispatch_queue_t property_list_request_operation_processing_queue() {
     if (!self) {
         return nil;
     }
-    
-    self.acceptableContentTypes = [[self class] defaultAcceptableContentTypes];
-    
+        
     self.propertyListReadOptions = NSPropertyListImmutable;
     
     return self;
@@ -112,7 +109,7 @@ static dispatch_queue_t property_list_request_operation_processing_queue() {
 }
 
 + (BOOL)canProcessRequest:(NSURLRequest *)request {
-    return [[self defaultAcceptableContentTypes] containsObject:[request valueForHTTPHeaderField:@"Accept"]] || [[self defaultAcceptablePathExtensions] containsObject:[[request URL] pathExtension]];
+    return [[[self class] acceptableContentTypes] containsObject:[request valueForHTTPHeaderField:@"Accept"]] || [[self defaultAcceptablePathExtensions] containsObject:[[request URL] pathExtension]];
 }
 
 - (void)setCompletionBlockWithSuccess:(void (^)(AFHTTPRequestOperation *operation, id responseObject))success

AFNetworking/AFXMLRequestOperation.m

@@ -40,7 +40,6 @@ static dispatch_queue_t xml_request_operation_processing_queue() {
 #endif
 @property (readwrite, nonatomic, retain) NSError *XMLError;
 
-+ (NSSet *)defaultAcceptableContentTypes;
 + (NSSet *)defaultAcceptablePathExtensions;
 @end
 
@@ -91,7 +90,7 @@ static dispatch_queue_t xml_request_operation_processing_queue() {
 }
 #endif
 
-+ (NSSet *)defaultAcceptableContentTypes {
++ (NSSet *)acceptableContentTypes {
     return [NSSet setWithObjects:@"application/xml", @"text/xml", nil];
 }
 
@@ -99,17 +98,6 @@ static dispatch_queue_t xml_request_operation_processing_queue() {
     return [NSSet setWithObjects:@"xml", nil];
 }
 
-- (id)initWithRequest:(NSURLRequest *)urlRequest {
-    self = [super initWithRequest:urlRequest];
-    if (!self) {
-        return nil;
-    }
-    
-    self.acceptableContentTypes = [[self class] defaultAcceptableContentTypes];
-    
-    return self;
-}
-
 - (void)dealloc {
     [_responseXMLParser release];
     
@@ -159,7 +147,7 @@ static dispatch_queue_t xml_request_operation_processing_queue() {
 }
 
 + (BOOL)canProcessRequest:(NSURLRequest *)request {
-    return [[self defaultAcceptableContentTypes] containsObject:[request valueForHTTPHeaderField:@"Accept"]] || [[self defaultAcceptablePathExtensions] containsObject:[[request URL] pathExtension]];
+    return [[[self class] acceptableContentTypes] containsObject:[request valueForHTTPHeaderField:@"Accept"]] || [[self defaultAcceptablePathExtensions] containsObject:[[request URL] pathExtension]];
 }
 
 - (void)setCompletionBlockWithSuccess:(void (^)(AFHTTPRequestOperation *operation, id responseObject))success