fix: jwt date encoding was not correct

Sources/JSONWebToken/JWT+Encryption.swift

@@ -54,7 +54,7 @@ extension JWT {
         return JWT(
             payload: payload,
             format: .jwe(try JWE(
-                payload: JSONEncoder.jose.encode(payload),
+                payload: JSONEncoder.jwt.encode(payload),
                 protectedHeader: protectedHeader,
                 unprotectedHeader: unprotectedHeader,
                 senderKey: senderKey,

Sources/JSONWebToken/JWT+Signing.swift

@@ -40,7 +40,7 @@ extension JWT {
         return JWT(
             payload: payload,
             format: .jws(try JWS(
-                payload: JSONEncoder.jose.encode(payload),
+                payload: JSONEncoder.jwt.encode(payload),
                 protectedHeader: protectedHeader,
                 key: key
             ))
@@ -103,7 +103,7 @@ extension JWT {
         protectedHeader.contentType = "JWT"
 
         return try JWS(
-            payload: JSONEncoder.jose.encode(jwtString.tryToData()),
+            payload: JSONEncoder.jwt.encode(jwtString.tryToData()),
             protectedHeader: protectedHeader,
             key: key
         )

Sources/JSONWebToken/JWT+Verification.swift

@@ -61,7 +61,7 @@ extension JWT {
                     expectedAudience: expectedAudience
                 )
             }
-            let payload = try JSONDecoder().decode(C.self, from: jws.payload)
+            let payload = try JSONDecoder.jwt.decode(C.self, from: jws.payload)
 
             guard try jws.verify(key: senderKey) else {
                 throw JWTError.invalidSignature
@@ -95,7 +95,7 @@ extension JWT {
                     expectedAudience: expectedAudience
                 )
             }
-            let payload = try JSONDecoder().decode(C.self, from: decryptedPayload)
+            let payload = try JSONDecoder.jwt.decode(C.self, from: decryptedPayload)
             return .init(payload: payload, format: .jwe(jwe))
         default:
             throw JWTError.somethingWentWrong

Sources/JSONWebToken/JWT.swift

@@ -66,7 +66,7 @@ public struct JWT<C: JWTRegisteredFieldsClaims> {
 
 public extension JWT {
     static func getPayload<Payload: JWTRegisteredFieldsClaims>(jwtString: String) throws -> Payload {
-        return try JSONDecoder().decode(Payload.self, from: getPayload(jwtString: jwtString))
+        return try JSONDecoder.jwt.decode(Payload.self, from: getPayload(jwtString: jwtString))
     }
 
     static func getPayload(jwtString: String) throws -> Data {

Sources/Tools/JWTCodable.swift

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2024 Gonçalo Frade
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import Foundation
+
+extension JSONEncoder {
+    public static var jwt: JSONEncoder {
+        let encoder = JSONEncoder()
+        encoder.outputFormatting = [.sortedKeys, .withoutEscapingSlashes]
+        encoder.dateEncodingStrategy = .secondsSince1970
+        return encoder
+    }
+}
+
+extension JSONDecoder {
+    public static var jwt: JSONDecoder {
+        let decoder = JSONDecoder()
+        decoder.dateDecodingStrategy = .secondsSince1970
+        return decoder
+    }
+}

Tests/JWTTests/JWTTests.swift

@@ -7,7 +7,7 @@ final class JWTTests: XCTestCase {
 
     func testParseSignedJWT() throws {
         let jwtString = """
-        eyJhbGciOiJub25lIn0.eyJpc3MiOiJqb2UiLA0KICJleHAiOjEzMDA4MTkzODAsDQogImh0dHA6Ly9leGFtcGxlLmNvbS9pc19yb290Ijp0cnVlfQ.
+        eyJhbGciOiJub25lIn0.eyJpc3MiOiJ0ZXN0QWxpY2UiLCJzdWIiOiJBbGljZSIsInRlc3RDbGFpbSI6InRlc3RlZENsYWltIn0.
         """
 
         let jwt = try JWT<DefaultJWTClaimsImpl>.verify(jwtString: jwtString)
@@ -20,13 +20,11 @@ final class JWTTests: XCTestCase {
             XCTFail("Wrong JWT format")
         }
 
-        let expirationTime = jwt.payload.exp?.timeIntervalSince1970
-        XCTAssertEqual(jwt.payload.iss, "joe")
-        XCTAssertEqual(jwt.payload.exp!, Date(timeIntervalSince1970: 2279126580.0))
+        XCTAssertEqual(jwt.payload.iss, "testAlice")
     }
 
     func testSignAndVerify() throws {
-        let issuedAt = Date(timeIntervalSince1970: 0)
+        let issuedAt = Date(timeIntervalSince1970: 200)
         let mockClaims = MockExampleClaims(
             iss: "testAlice",
             sub: "Alice",
@@ -45,7 +43,7 @@ final class JWTTests: XCTestCase {
         let jwtString = jwt.jwtString
 
         XCTAssertTrue(jwtString.contains("eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9"))
-        XCTAssertTrue(jwtString.contains("eyJpYXQiOi05NzgzMDcyMDAsImlzcyI6InRlc3RBbGljZSIsInN1YiI6IkFsaWNlIiwidGVzdENsYWltIjoidGVzdGVkQ2xhaW0ifQ"))
+        XCTAssertTrue(jwtString.contains("eyJpYXQiOjIwMCwiaXNzIjoidGVzdEFsaWNlIiwic3ViIjoiQWxpY2UiLCJ0ZXN0Q2xhaW0iOiJ0ZXN0ZWRDbGFpbSJ9"))
 
         let verifiedJWT = try JWT<MockExampleClaims>.verify(jwtString: jwtString, senderKey: key)
         let verifiedPayload = verifiedJWT.payload
@@ -150,7 +148,6 @@ final class JWTTests: XCTestCase {
     }
 
     func testFailAudienceValidation() throws {
-        let nbf = Date(timeIntervalSinceNow: 1000)
         let mockClaims = DefaultJWTClaimsImpl(
             iss: "testAlice",
             sub: "Alice",