19 #import <Foundation/Foundation.h> 
   21 NS_ASSUME_NONNULL_BEGIN
 
   30 - (instancetype)init NS_UNAVAILABLE;
 
   38 + (NSString *)encodeBase64urlNoPadding:(NSData *)data;
 
   45 + (nullable NSString *)randomURLSafeStringWithSize:(NSUInteger)size;
 
   51 + (NSData *)sha256:(NSString *)inputString;
 
   57 + (nullable NSString *)redact:(nullable NSString *)inputString;
 
   63 + (NSString*)formUrlEncode:(NSString*)inputString;