CBORObjC（OC原生实现CBOR）

CBORObjC

用Objective-C原生实现 CBOR (RFC 7049 Concise Binary Object Representation) 编解码

• 支持半精度

• 支持最优最短编码（默认）

• 支持对象属性构建编码顺序控制

• 建议使用cbor.me进行检验编解码结果

• 支持原生数据类型进行CBOR编解码

  • 基础数据类型，例如：NSInteger, NSUInteger, float, double, BOOL等等

  • NSNumber

  • NSArray

  • NSDictionary

  • NSData (byte string)

  • NSString

  • NSDate

  • NSNull

• 支持实现CBORModel协议对象进行CBOR编解码

安装方式

• CocoaPods

pod 'CBORObjC'

解码

解析为原生对象

• +[CBORParser decodeData:]

Byte raw[] = {
 0x9f, // indefinite array
 0x18, 255, // unsigned 255
 0x9b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 2, // array length is 2
 0x18, 1, // unsigned 1
 0x79, 0x00, 3, // string length is 3
 0x41, 0x42, 0x43, // @"ABC"
 0x79, 0x00, 3, // string length is 3
 0x41, 0x42, 0x43, // @"ABC"
 0xff // indefinite end
};
​
id ret = [CBORParser decodeData:[NSData dataWithBytes:&raw length:sizeof(raw)]];
// ret is @[@(255), @[@(1), @"ABC"], @"ABC"]  

解析为指定对象

• +[CBORParser decodeClass:fromData:]

@interface MyModel: NSObject <CBORModel>
@property (nonatomic, assign) NSInteger value;
@end
@implementation MyModel
@end
​
Byte raw[] = {
 0x8f, // indefinite dictionary
 0xA1, // dictionary length is 1
 0x65, 0x76, 0x61, 0x6C, 0x75, 0x65, // key (string length is 5): "value"
 0x1, // value (unsigned 1): 1
 0xff // indefinite end
};
​
id ret = [CBORParser decodeClass:[MyModel class] fromData:[NSData dataWithBytes:&raw length:sizeof(raw)]];
// ret is MyModel instance and ret.value = 1

编码

自定义编码原生对象

• [CBORParser encodeObject:major:minor:]

// obj can be NSObject, NSData, NSDate, NSNumber, NSString, NSArray, NSDictionary, NSNull...
[CBORParser encodeObject:@(1)]; // 0x01
[CBORParser encodeObject:@(1) major:CBORMajorTypeUnsigned minor:CBORLengthTypeUInt8]; // 0x18, 0x01
[CBORParser encodeObject:@(1) major:CBORMajorTypeAdditional]; // 0xe1 (simple value 1)

对实现CBORModel协议对象编码

• 自定义属性的Major/Minor类型

• 自定义属性的顺序

• JSON编解码；参考： YYModel

#import "CBOR.h"
​
@interface CBORModel: NSObject <CBORModel>
​
@property (nonatomic, assign) NSUInteger uintValue;
@property (nonatomic, assign) float floatValue;
@property (nonatomic, assign) double doubleValue;
@property (nonatomic, copy) NSString *stringValue;
@property (nonatomic, copy) NSDate *dateValue;
// rename to tagStringValue
@property (nonatomic, copy) NSString *tagValue;
@property (nonatomic, copy) NSString *ignoredValue;
​
@end
​
@implementation CBORModel
​
+ (NSDictionary<NSString *,id> *)modelCustomPropertyMapper {
 return @{
  @"tagValue": @"tagStringValue"
 };
}
/// 自定义主要类型
+ (NSDictionary<NSString *, NSNumber *> *)modelCustomPropertyMajor {
 return @{
 // 可以不加CBORLengthTypeUInt8，那么Tag的子元素将根据自身最小所需长度设置
 @"tagValue": @(CBORMajorTypeTag | CBORLengthTypeUInt8),
 @"doubleValue": @(CBORMajorTypeAdditional)
 };
}
​
+ (NSDictionary<NSString *,NSNumber *> *)modelCustomPropertyMinor {
 return @{
 @"tagValue": @(CBORTagTypeStandardDateTimeString),
 @"doubleValue": @(CBORAdditionalTypeDouble)
 };
}
​
+ (NSArray<NSString *> *)modelPropertyBlacklist {
 return @[@"ignoredValue"];
}
​
- (NSString *)description {
 return [NSString stringWithFormat:@"[Model] u: %zd; f:%.2f, d:%.2f s: %@; d: %@, t: %@, i: %@", _uintValue, _floatValue, _doubleValue, _stringValue, _dateValue, _tagValue, _ignoredValue];
}
​
- (BOOL)isEqualTo:(id)object {
 if (![object isKindOfClass:[self class]]) return NO;
 CBORModel *model = object;
 return [self.stringValue isEqualToString:model.stringValue] && (self.uintValue == model.uintValue);
}
​
@end

CBORModel *model = [[CBORModel alloc] init];
model.uintValue = 1;
model.floatValue = 1.0f;
model.doubleValue = 1.0;
model.stringValue = @"s";
model.tagValue = @"t";
model.dateValue = nil;//[NSDate dateWithTimeIntervalSince1970:1363896240];
model.ignoredValue = @"ignored";
​
Byte raw[] = {
 0xA6, // map(6)

 0x69, 0x64, 0x61, 0x74, 0x65, 0x56, 0x61, 0x6C, 0x75, 0x65, // key: "dateValue"
 0xf6, // value: null
​
 0x6E, 0x74, 0x61, 0x67, 0x53, 0x74, 0x72, 0x69, 0x6E, 0x67, 0x56, 0x61, 0x6C, 0x75, 0x65, // key: "tagStringValue"
//        0xc0, 0x61, 0x74,// value: tag(0), text(1), "t",
 0xc0, 0x78, 0x01, 0x74, // value: tag(0), text(1) "t"
​
 0x69, 0x75, 0x69, 0x6E, 0x74, 0x56, 0x61, 0x6C, 0x75, 0x65,// key: "uintValue"
 0x01, // value: unsigned(1)
​
 0x6B, 0x73, 0x74, 0x72, 0x69, 0x6E, 0x67, 0x56, 0x61, 0x6C, 0x75, 0x65, // key: "stringValue"
 0x61, 0x73, // value: "s"
​
 0x6A, 0x66, 0x6C, 0x6F, 0x61, 0x74, 0x56, 0x61, 0x6C, 0x75, 0x65,// key: "floatValue"
 0xF9, 0x3C, 0x00, // value: half(1.0)
​
 0x6B, 0x64, 0x6F, 0x75, 0x62, 0x6C, 0x65, 0x56, 0x61, 0x6C, 0x75, 0x65, // key: "doubleValue"
 0xfb, 0x3f, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // value: double(1.0)
};
NSData *encodeData = [NSData dataWithBytes:&raw length:sizeof(raw)];
​
// Decode
[CBORParser decodeClass:[CBORModel class] fromData:encodeData]; // result is model
// Encode
[CBORParser encodeObject:model]; // result is encodeData

参考源码: CBORObjC