Add nonce test for PromotionalOfferV2SignatureCreatorTest

Author: alexanderjordanbaker

src/main/java/com/apple/itunes/storekit/signature/JWSSignatureCreator.java

@@ -49,7 +49,7 @@ public JWSSignatureCreator(String audience, String signingKey, String keyId, Str
     protected String createSignature(Map<String, ?> featureSpecificClaims) {
         Map<String, Object> claims = new HashMap<>(featureSpecificClaims);
         claims.put(BUNDLE_ID_KEY, bundleId);
-        claims.put(NONCE_KEY, UUID.randomUUID().toString());
+        claims.put(NONCE_KEY, createNonce().toString());
         return JWT.create()
                 .withAudience(audience)
                 .withIssuedAt(Instant.now())
@@ -58,4 +58,8 @@ protected String createSignature(Map<String, ?> featureSpecificClaims) {
                 .withPayload(claims)
                 .sign(Algorithm.ECDSA256(signingKey));
     }
+
+    protected UUID createNonce() {
+        return UUID.randomUUID();
+    }
 }

src/test/java/com/apple/itunes/storekit/offers/PromotionalOfferV2SignatureCreatorTest.java

@@ -74,4 +74,20 @@ void testProductIdMissing() throws Exception {
             Assertions.assertThrows(IllegalArgumentException.class, () -> signatureCreator.createSignature(null, OFFER_IDENTIFIER, TRANSACTION_ID));
         }
     }
+
+    @Test
+    void testNonceIsProvided() throws Exception {
+        try (InputStream key = this.getClass().getClassLoader().getResourceAsStream("certs/testSigningKey.p8")) {
+            Assertions.assertNotNull(key);
+            UUID nonce = UUID.randomUUID();
+            PromotionalOfferV2SignatureCreator signatureCreator = new PromotionalOfferV2SignatureCreator(new String(key.readAllBytes()), KEY_ID, ISSUER_ID, BUNDLE_ID) {
+                protected UUID createNonce() {
+                    return nonce;
+                }
+            };
+            String signature = signatureCreator.createSignature(PRODUCT_ID, OFFER_IDENTIFIER, TRANSACTION_ID);
+            DecodedJWT decodedJWT = JWT.decode(signature);
+            Assertions.assertEquals(decodedJWT.getClaim("nonce").asString(), nonce.toString());
+        }
+    }
 }