refactor: Add keyID and contentType to JOSEHeader

Author: kylef

Sources/JWT/JOSEHeader.swift

@@ -10,23 +10,59 @@ import Foundation
 
 
 struct JOSEHeader: Codable {
-  var type: String?
+  /// The "alg" (algorithm) identifies the cryptographic algorithm used to secure the JWS
   var algorithm: String?
 
+  /// jwu
+  // TODO
+
+  /// jwk
+  // TODO
+
+  /// The "kid" (key ID) is a hint indicating which key was used to secure the JWS
+  var keyID: String?
+
+  /// x5u
+  // TODO
+
+  /// x5c
+  // TODO
+
+  /// x5t
+  // TODO
+
+  /// x5t#S256
+  // TODO
+
+  /// The "typ" (type) is used by JWS applications to declare the media type [IANA.MediaTypes] of this complete JWS
+  var type: String?
+
+  /// The "cty" (content type) is used by JWS application to declare the media type [IANA.MediaTypes] of the secured content (the payload).
+  var contentType: String?
+
+  /// The "crit" (critical) indicates that extensions to JWS, JWE and/or [JWA] are being used that MUST be understood and processed
+  // TODO
+
   init(from decoder: Decoder) throws {
     let container = try decoder.container(keyedBy: CodingKeys.self)
-    type = try container.decodeIfPresent(String.self, forKey: .type)
     algorithm = try container.decodeIfPresent(String.self, forKey: .algorithm)
+    keyID = try container.decodeIfPresent(String.self, forKey: .keyID)
+    type = try container.decodeIfPresent(String.self, forKey: .type)
+    contentType = try container.decodeIfPresent(String.self, forKey: .contentType)
   }
 
   func encode(to encoder: Encoder) throws {
     var container = encoder.container(keyedBy: CodingKeys.self)
-    try container.encodeIfPresent(type, forKey: .type)
     try container.encodeIfPresent(algorithm, forKey: .algorithm)
+    try container.encodeIfPresent(keyID, forKey: .keyID)
+    try container.encodeIfPresent(type, forKey: .type)
+    try container.encodeIfPresent(contentType, forKey: .contentType)
   }
 
   enum CodingKeys: String, CodingKey {
-    case type = "typ"
     case algorithm = "alg"
+    case keyID = "kid"
+    case type = "typ"
+    case contentType = "cty"
   }
 }