From 1d9f762505377a981073f8cd908c912f55966124 Mon Sep 17 00:00:00 2001
From: Paul Latzelsperger <43503240+paullatzelsperger@users.noreply.github.com>
Date: Tue, 21 Nov 2023 10:30:41 +0100
Subject: [PATCH] feat!: avoid empty nested arrays when generating VP (#178)

---
 .../core/PresentationGeneratorImpl.java           | 15 +++++++--------
 .../verification/AccessTokenVerifierImpl.java     |  2 +-
 .../core/PresentationGeneratorImplTest.java       |  2 +-
 3 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/core/identity-hub-core/src/main/java/org/eclipse/edc/identityhub/core/PresentationGeneratorImpl.java b/core/identity-hub-core/src/main/java/org/eclipse/edc/identityhub/core/PresentationGeneratorImpl.java
index 8f695dfce..d7bc65fe9 100644
--- a/core/identity-hub-core/src/main/java/org/eclipse/edc/identityhub/core/PresentationGeneratorImpl.java
+++ b/core/identity-hub-core/src/main/java/org/eclipse/edc/identityhub/core/PresentationGeneratorImpl.java
@@ -14,7 +14,6 @@
 
 package org.eclipse.edc.identityhub.core;
 
-import jakarta.json.Json;
 import jakarta.json.JsonObject;
 import org.eclipse.edc.identityhub.spi.generator.PresentationCreatorRegistry;
 import org.eclipse.edc.identityhub.spi.generator.PresentationGenerator;
@@ -26,6 +25,7 @@
 import org.eclipse.edc.spi.result.Result;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -68,26 +68,25 @@ public Result<PresentationResponse> createPresentation(List<VerifiableCredential
         var ldpVcs = ofNullable(groups.get(JSON_LD)).orElseGet(List::of);
 
 
-        String vpToken;
+        var vpToken = new ArrayList<>();
+
         if (defaultFormatVp == JSON_LD) { // LDP-VPs cannot contain JWT VCs
-            var arrayBuilder = Json.createArrayBuilder();
             if (!ldpVcs.isEmpty()) {
                 JsonObject ldpVp = registry.createPresentation(ldpVcs, CredentialFormat.JSON_LD);
-                arrayBuilder.add(ldpVp);
+                vpToken.add(ldpVp.toString());
             }
 
             if (!jwtVcs.isEmpty()) {
                 monitor.warning("The VP was requested in %s format, but the request yielded %s JWT-VCs, which cannot be transported in a LDP-VP. A second VP will be returned, containing JWT-VCs".formatted(JSON_LD, jwtVcs.size()));
                 String jwtVp = registry.createPresentation(jwtVcs, CredentialFormat.JWT);
-                arrayBuilder.add(jwtVp);
+                vpToken.add(jwtVp);
             }
 
-            vpToken = arrayBuilder.build().toString();
         } else { //defaultFormatVp == JWT
-            vpToken = registry.createPresentation(credentials, CredentialFormat.JWT);
+            vpToken.add(registry.createPresentation(credentials, CredentialFormat.JWT));
         }
 
-        var presentationResponse = new PresentationResponse(new Object[] {vpToken}, null);
+        var presentationResponse = new PresentationResponse(vpToken.toArray(new Object[0]), null);
         return Result.success(presentationResponse);
     }
 }
diff --git a/core/identity-hub-core/src/main/java/org/eclipse/edc/identityhub/token/verification/AccessTokenVerifierImpl.java b/core/identity-hub-core/src/main/java/org/eclipse/edc/identityhub/token/verification/AccessTokenVerifierImpl.java
index 770dd6374..a29cd8b69 100644
--- a/core/identity-hub-core/src/main/java/org/eclipse/edc/identityhub/token/verification/AccessTokenVerifierImpl.java
+++ b/core/identity-hub-core/src/main/java/org/eclipse/edc/identityhub/token/verification/AccessTokenVerifierImpl.java
@@ -68,7 +68,7 @@ public Result<List<String>> verify(String token) {
 
         // make sure an access_token claim exists
         var claimToken = validationResult.getContent();
-        if (claimToken.getClaim("access_token") == null) {
+        if (claimToken.getClaim(ACCES_TOKEN_CLAIM) == null) {
             return failure("No 'access_token' claim was found on ID Token.");
         }
 
diff --git a/core/identity-hub-core/src/test/java/org/eclipse/edc/identityhub/core/PresentationGeneratorImplTest.java b/core/identity-hub-core/src/test/java/org/eclipse/edc/identityhub/core/PresentationGeneratorImplTest.java
index f71ddba6e..57c40f1a6 100644
--- a/core/identity-hub-core/src/test/java/org/eclipse/edc/identityhub/core/PresentationGeneratorImplTest.java
+++ b/core/identity-hub-core/src/test/java/org/eclipse/edc/identityhub/core/PresentationGeneratorImplTest.java
@@ -63,7 +63,7 @@ void generate_noCredentials() {
         List<VerifiableCredentialContainer> ldpVcs = List.of();
 
         var result = presentationGenerator.createPresentation(ldpVcs, null);
-        assertThat(result).isSucceeded();
+        assertThat(result).isSucceeded().matches(pr -> pr.vpToken().length == 0, "VP Tokens should be empty");
     }
 
     @Test