add response type "arraybuffer" support for iOS

src/ios/BinaryResponseSerializer.m

@@ -0,0 +1,126 @@
+#import "BinaryResponseSerializer.h"
+
+static NSError * AFErrorWithUnderlyingError(NSError *error, NSError *underlyingError) {
+  if (!error) {
+    return underlyingError;
+  }
+
+  if (!underlyingError || error.userInfo[NSUnderlyingErrorKey]) {
+    return error;
+  }
+
+  NSMutableDictionary *mutableUserInfo = [error.userInfo mutableCopy];
+  mutableUserInfo[NSUnderlyingErrorKey] = underlyingError;
+
+  return [[NSError alloc] initWithDomain:error.domain code:error.code userInfo:mutableUserInfo];
+}
+
+static BOOL AFErrorOrUnderlyingErrorHasCodeInDomain(NSError *error, NSInteger code, NSString *domain) {
+  if ([error.domain isEqualToString:domain] && error.code == code) {
+    return YES;
+  } else if (error.userInfo[NSUnderlyingErrorKey]) {
+    return AFErrorOrUnderlyingErrorHasCodeInDomain(error.userInfo[NSUnderlyingErrorKey], code, domain);
+  }
+
+  return NO;
+}
+
+@implementation BinaryResponseSerializer
+
++ (instancetype)serializer {
+  BinaryResponseSerializer *serializer = [[self alloc] init];
+  return serializer;
+}
+
+- (instancetype)init {
+  self = [super init];
+
+  if (!self) {
+    return nil;
+  }
+
+  self.acceptableContentTypes = nil;
+
+  return self;
+}
+
+- (NSString*)decodeResponseData:(NSData*)rawResponseData withEncoding:(CFStringEncoding)cfEncoding {
+  NSStringEncoding nsEncoding;
+  NSString* decoded = nil;
+
+  if (cfEncoding != kCFStringEncodingInvalidId) {
+    nsEncoding = CFStringConvertEncodingToNSStringEncoding(cfEncoding);
+  }
+
+  NSStringEncoding supportedEncodings[6] = {
+    NSUTF8StringEncoding, NSWindowsCP1252StringEncoding, NSISOLatin1StringEncoding,
+    NSISOLatin2StringEncoding, NSASCIIStringEncoding, NSUnicodeStringEncoding
+  };
+
+  for (int i = 0; i < sizeof(supportedEncodings) / sizeof(NSStringEncoding) && !decoded; ++i) {
+    if (cfEncoding == kCFStringEncodingInvalidId || nsEncoding == supportedEncodings[i]) {
+      decoded = [[NSString alloc] initWithData:rawResponseData encoding:supportedEncodings[i]];
+    }
+  }
+
+  return decoded;
+}
+
+- (CFStringEncoding) getEncoding:(NSURLResponse *)response {
+  CFStringEncoding encoding = kCFStringEncodingInvalidId;
+
+  if (response.textEncodingName) {
+    encoding = CFStringConvertIANACharSetNameToEncoding((CFStringRef)response.textEncodingName);
+  }
+
+  return encoding;
+}
+
+#pragma mark -
+
+- (BOOL)validateResponse:(NSHTTPURLResponse *)response
+                    data:(NSData *)data
+                   error:(NSError * __autoreleasing *)error
+{
+  if (response && [response isKindOfClass:[NSHTTPURLResponse class]]) {
+    if (self.acceptableStatusCodes && ![self.acceptableStatusCodes containsIndex:(NSUInteger)response.statusCode] && [response URL]) {
+      NSMutableDictionary *mutableUserInfo = [@{
+        NSLocalizedDescriptionKey: [NSString stringWithFormat:NSLocalizedStringFromTable(@"Request failed: %@ (%ld)", @"AFNetworking", nil), [NSHTTPURLResponse localizedStringForStatusCode:response.statusCode], (long)response.statusCode],
+        NSURLErrorFailingURLErrorKey: [response URL],
+        AFNetworkingOperationFailingURLResponseErrorKey: response,
+      } mutableCopy];
+
+      if (data) {
+        mutableUserInfo[AFNetworkingOperationFailingURLResponseDataErrorKey] = data;
+
+        // trying to decode error message in body
+        mutableUserInfo[AFNetworkingOperationFailingURLResponseBodyErrorKey] = [self decodeResponseData:data withEncoding:[self getEncoding:response]];
+      }
+
+      if (error) {
+        *error = [NSError errorWithDomain:AFURLResponseSerializationErrorDomain code:NSURLErrorBadServerResponse userInfo:mutableUserInfo];
+      }
+
+      return NO;
+    }
+  }
+
+  return YES;
+}
+
+#pragma mark - AFURLResponseSerialization
+
+- (id)responseObjectForResponse:(NSURLResponse *)response
+                           data:(NSData *)data
+                          error:(NSError *__autoreleasing *)error
+{
+  if (![self validateResponse:(NSHTTPURLResponse *)response data:data error:error]) {
+    if (!error || AFErrorOrUnderlyingErrorHasCodeInDomain(*error, NSURLErrorCannotDecodeContentData, AFURLResponseSerializationErrorDomain)) {
+      return nil;
+    }
+  }
+
+  return [data base64EncodedStringWithOptions:0];
+}
+
+@end