Add guard to handle index out of range exception (#83)

Kitura · Dec 5, 2019 · 0d43542 · 0d43542
1 parent d4993d2
commit 0d43542
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/Sources/SwiftJWT/JWTDecoder.swift b/Sources/SwiftJWT/JWTDecoder.swift
@@ -75,7 +75,8 @@ public class JWTDecoder: BodyDecoder {
     public func decode<T : Decodable>(_ type: T.Type, fromString: String) throws -> T {
         // Seperate the JWT into the headers and claims.
         let components = fromString.components(separatedBy: ".")
-        guard let headerData = JWTDecoder.data(base64urlEncoded: components[0]),
+        guard components.count > 1,
+         let headerData = JWTDecoder.data(base64urlEncoded: components[0]),
             let claimsData = JWTDecoder.data(base64urlEncoded: components[1])
         else {
             throw JWTError.invalidJWTString