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noppoMannoppoMan
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Merge pull request #1 from Hexaville/base64
use third party's Base64Encoder to avoid crash
2 parents 2dc00c1 + f87564e commit 48b2377

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2 files changed

+366
-6
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‎Sources/DynamodbSessionStore/Base64.swift‎

Lines changed: 362 additions & 0 deletions
Original file line numberDiff line numberDiff line change
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/// Encodes and decodes bytes using the
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/// Base64 encoding
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///
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/// https://en.wikipedia.org/wiki/Base64
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extension UInt8 {
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/// '\t'
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public static let horizontalTab: UInt8 = 0x9
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/// '\n'
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public static let newLine: UInt8 = 0xA
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/// '\r'
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public static let carriageReturn: UInt8 = 0xD
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/// ' '
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public static let space: UInt8 = 0x20
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/// !
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public static let exclamation: UInt8 = 0x21
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/// "
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public static let quote: UInt8 = 0x22
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/// #
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public static let numberSign: UInt8 = 0x23
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/// $
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public static let dollar: UInt8 = 0x24
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/// %
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public static let percent: UInt8 = 0x25
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/// &
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public static let ampersand: UInt8 = 0x26
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/// '
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public static let apostrophe: UInt8 = 0x27
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/// (
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public static let leftParenthesis: UInt8 = 0x28
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/// )
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public static let rightParenthesis: UInt8 = 0x29
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/// *
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public static let asterisk: UInt8 = 0x2A
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/// +
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public static let plus: UInt8 = 0x2B
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/// ,
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public static let comma: UInt8 = 0x2C
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/// -
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public static let hyphen: UInt8 = 0x2D
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/// .
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public static let period: UInt8 = 0x2E
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/// /
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public static let forwardSlash: UInt8 = 0x2F
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/// 0
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public static let zero: UInt8 = 0x30
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/// 9
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public static let nine: UInt8 = 0x39
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/// :
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public static let colon: UInt8 = 0x3A
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/// ;
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public static let semicolon: UInt8 = 0x3B
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/// =
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public static let equals: UInt8 = 0x3D
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/// ?
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public static let questionMark: UInt8 = 0x3F
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/// @
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public static let at: UInt8 = 0x40
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/// A
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public static let A: UInt8 = 0x41
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/// B
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public static let B: UInt8 = 0x42
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/// C
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public static let C: UInt8 = 0x43
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/// D
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public static let D: UInt8 = 0x44
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/// E
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public static let E: UInt8 = 0x45
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/// F
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public static let F: UInt8 = 0x46
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/// Z
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public static let Z: UInt8 = 0x5A
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/// [
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public static let leftSquareBracket: UInt8 = 0x5B
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/// \
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public static let backSlash: UInt8 = 0x5C
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/// ]
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public static let rightSquareBracket: UInt8 = 0x5D
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/// _
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public static let underscore: UInt8 = 0x5F
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/// a
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public static let a: UInt8 = 0x61
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/// f
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public static let f: UInt8 = 0x66
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/// z
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public static let z: UInt8 = 0x7A
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/// ~
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public static let tilda: UInt8 = 0x7E
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}
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final class Base64Encoder {
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/// Static shared instance
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static let shared = Base64Encoder.regular
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/// Standard Base64Encoder
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static var regular: Base64Encoder {
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return Base64Encoder()
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}
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// Base64URLEncoder
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// - note: uses hyphens and underscores
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// in place of plus and forwardSlash
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static var url: Base64Encoder {
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let encodeMap: Base64Encoder.ByteMap = { byte in
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switch byte {
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case 62:
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return 0x2D
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case 63:
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return 0x5F
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default:
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return nil
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}
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}
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let decodeMap: Base64Encoder.ByteMap = { byte in
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switch byte {
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case 0x2D:
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return 62
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case 0x5F:
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return 63
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default:
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return nil
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}
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}
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return Base64Encoder(
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padding: nil,
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encodeMap: encodeMap,
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decodeMap: decodeMap
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)
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}
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/// Maps binary format to base64 encoding
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static fileprivate let encodingTable: [UInt8: UInt8] = [
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0: 0x41, 1: 0x42, 2: 0x43, 3: 0x44,
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4: 0x45, 5: 0x46, 6: 0x47, 7: 0x48,
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8: 0x49, 9: 0x4A, 10: 0x4B, 11: 0x4C,
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12: 0x4D, 13: 0x4E, 14: 0x4F, 15: 0x50,
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16: 0x51, 17: 0x52, 18: 0x53, 19: 0x54,
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20: 0x55, 21: 0x56, 22: 0x57, 23: 0x58,
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24: 0x59, 25: 0x5A, 26: 0x61, 27: 0x62,
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28: 0x63, 29: 0x64, 30: 0x65, 31: 0x66,
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32: 0x67, 33: 0x68, 34: 0x69, 35: 0x6A,
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36: 0x6B, 37: 0x6C, 38: 0x6D, 39: 0x6E,
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40: 0x6F, 41: 0x70, 42: 0x71, 43: 0x72,
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44: 0x73, 45: 0x74, 46: 0x75, 47: 0x76,
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48: 0x77, 49: 0x78, 50: 0x79, 51: 0x7A,
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52: 0x30, 53: 0x31, 54: 0x32, 55: 0x33,
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56: 0x34, 57: 0x35, 58: 0x36, 59: 0x37,
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60: 0x38, 61: 0x39, 62: .plus, 63: .forwardSlash
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]
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/// Maps base64 encoding into binary format
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static fileprivate let decodingTable: [UInt8: UInt8] = [
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0x41: 0, 0x42: 1, 0x43: 2, 0x44: 3,
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0x45: 4, 0x46: 5, 0x47: 6, 0x48: 7,
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0x49: 8, 0x4A: 9, 0x4B: 10, 0x4C: 11,
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0x4D: 12, 0x4E: 13, 0x4F: 14, 0x50: 15,
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0x51: 16, 0x52: 17, 0x53: 18, 0x54: 19,
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0x55: 20, 0x56: 21, 0x57: 22, 0x58: 23,
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0x59: 24, 0x5A: 25, 0x61: 26, 0x62: 27,
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0x63: 28, 0x64: 29, 0x65: 30, 0x66: 31,
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0x67: 32, 0x68: 33, 0x69: 34, 0x6A: 35,
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0x6B: 36, 0x6C: 37, 0x6D: 38, 0x6E: 39,
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0x6F: 40, 0x70: 41, 0x71: 42, 0x72: 43,
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0x73: 44, 0x74: 45, 0x75: 46, 0x76: 47,
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0x77: 48, 0x78: 49, 0x79: 50, 0x7A: 51,
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0x30: 52, 0x31: 53, 0x32: 54, 0x33: 55,
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0x34: 56, 0x35: 57, 0x36: 58, 0x37: 59,
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0x38: 60, 0x39: 61, .plus: 62, .forwardSlash: 63
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]
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/// Typealias for optionally mapping a byte
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fileprivate typealias ByteMap = (UInt8) -> UInt8?
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/// Byte to use for padding base64
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/// if nil, no padding will be used
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fileprivate let padding: UInt8?
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/// If set, bytes returned will have priority
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/// over the encoding table. Encoding table
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/// will be used as a fallback
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fileprivate let encodeMap: ByteMap?
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/// If set, bytes returned will have priority
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/// over the decoding table. Decoding table
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/// will be used as a fallback
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fileprivate let decodeMap: ByteMap?
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/// Creates a new Base64 encoder
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fileprivate init(
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padding: UInt8? = .equals,
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encodeMap: ByteMap? = nil,
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decodeMap: ByteMap? = nil
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) {
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self.padding = padding
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self.encodeMap = encodeMap
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self.decodeMap = decodeMap
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}
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/// Encodes bytes into Base64 format
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func encode(_ bytes: [UInt8]) -> [UInt8] {
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if bytes.count == 0 {
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return []
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}
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let len = bytes.count
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var offset: Int = 0
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var c1: UInt8
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var c2: UInt8
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var result: [UInt8] = []
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while offset < len {
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c1 = bytes[offset] & 0xff
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offset += 1
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result.append(encode((c1 >> 2) & 0x3f))
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c1 = (c1 & 0x03) << 4
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if offset >= len {
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result.append(encode(c1 & 0x3f))
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if let padding = self.padding {
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result.append(padding)
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result.append(padding)
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}
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break
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}
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c2 = bytes[offset] & 0xff
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offset += 1
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c1 |= (c2 >> 4) & 0x0f
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result.append(encode(c1 & 0x3f))
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c1 = (c2 & 0x0f) << 2
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if offset >= len {
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result.append(encode(c1 & 0x3f))
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if let padding = self.padding {
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result.append(padding)
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}
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break
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}
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c2 = bytes[offset] & 0xff
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offset += 1
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c1 |= (c2 >> 6) & 0x03
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result.append(encode(c1 & 0x3f))
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result.append(encode(c2 & 0x3f))
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}
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return result
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}
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/// Decodes bytes into binary format
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func decode(_ s: [UInt8]) -> [UInt8] {
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let maxolen = s.count
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var off: Int = 0
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var olen: Int = 0
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var result = [UInt8](repeating: 0, count: maxolen)
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var c1: UInt8
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var c2: UInt8
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var c3: UInt8
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var c4: UInt8
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var o: UInt8
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while off < s.count - 1 && olen < maxolen {
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c1 = decode(s[off])
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off += 1
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c2 = decode(s[off])
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off += 1
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if c1 == UInt8.max || c2 == UInt8.max {
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break
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}
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o = c1 << 2
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o |= (c2 & 0x30) >> 4
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result[olen] = o
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olen += 1
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if olen >= maxolen || off >= s.count {
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break
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}
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c3 = decode(s[off])
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off += 1
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if c3 == UInt8.max {
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break
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}
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o = (c2 & 0x0f) << 4
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o |= (c3 & 0x3c) >> 2
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result[olen] = o
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olen += 1
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if olen >= maxolen || off >= s.count {
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break
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}
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c4 = decode(s[off])
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off += 1
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if c4 == UInt8.max {
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break
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}
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o = (c3 & 0x03) << 6
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o |= c4
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result[olen] = o
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olen += 1
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}
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return Array(result[0..<olen])
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}
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// MARK: Private
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private func encode(_ x: UInt8) -> UInt8 {
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return encodeMap?(x)
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?? Base64Encoder.encodingTable[x]
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?? UInt8.max
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}
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private func decode(_ x: UInt8) -> UInt8 {
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return decodeMap?(x)
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?? Base64Encoder.decodingTable[x]
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?? UInt8.max
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}
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}

‎Sources/DynamodbSessionStore/DynamodbSessionStore.swift‎

Lines changed: 4 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -33,18 +33,16 @@ public struct DynamodbSessionStore: SessionStoreProvider {
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throw DynamodbSessionStoreError.couldNotFindItem
3434
}
3535

36-
guard let data = Data(base64Encoded: jsonStr, options: Data.Base64DecodingOptions(rawValue: 0)) else {
37-
return nil
38-
}
39-
40-
return try JSONSerialization.jsonObject(with: data, options: []) as? [String: Any]
36+
let encodedData = Data(bytes: Base64Encoder.shared.decode(Array(jsonStr.utf8)))
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return try JSONSerialization.jsonObject(with: encodedData, options: []) as? [String: Any]
4138
}
4239

4340
public func write(value: [String : Any], forKey: String, ttl: Int?) throws {
4441
let data = try JSONSerialization.data(withJSONObject: value, options: [])
42+
let stringValue = String(bytes: Base64Encoder.shared.encode(data.bytes), encoding: .utf8) ?? ""
4543
var item: [String: Dynamodb.AttributeValue] = [
4644
"session_id" : Dynamodb.AttributeValue(s: forKey),
47-
"value": Dynamodb.AttributeValue(s: data.base64EncodedString())
45+
"value": Dynamodb.AttributeValue(s: stringValue)
4846
]
4947

5048
if let ttl = ttl {

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