Don't throw NPE on GoogleCredential.Builder when scopes not set

CydeWeys · neozwu · commit 44a6f91efd41 · 2017-06-30T15:36:53.000-07:00
The list of account scopes in the GoogleCredential.Builder starts off uninitialized (i.e. null), meaning that calling the .build() method throws an NPE unless setServiceAccountScopes() is called. There are no other fields in the builder that are required to be called, and this doesn't seem to be required intentionally, so make the Builder resilient to it being null and have it correctly interpret that as an empty list of scopes. ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=133587273
diff --git a/google-api-client/src/main/java/com/google/api/client/googleapis/auth/oauth2/GoogleCredential.java b/google-api-client/src/main/java/com/google/api/client/googleapis/auth/oauth2/GoogleCredential.java
@@ -325,7 +325,10 @@ protected GoogleCredential(Builder builder) {
     } else {
       serviceAccountId = Preconditions.checkNotNull(builder.serviceAccountId);
       serviceAccountProjectId = builder.serviceAccountProjectId;
-      serviceAccountScopes = Collections.unmodifiableCollection(builder.serviceAccountScopes);
+      serviceAccountScopes =
+          (builder.serviceAccountScopes == null)
+              ? Collections.<String>emptyList()
+              : Collections.unmodifiableCollection(builder.serviceAccountScopes);
       serviceAccountPrivateKey = builder.serviceAccountPrivateKey;
       serviceAccountPrivateKeyId = builder.serviceAccountPrivateKeyId;
       serviceAccountUser = builder.serviceAccountUser;
diff --git a/google-api-client/src/test/java/com/google/api/client/googleapis/auth/oauth2/GoogleCredentialTest.java b/google-api-client/src/test/java/com/google/api/client/googleapis/auth/oauth2/GoogleCredentialTest.java
@@ -133,6 +133,24 @@ public void testCreateScoped() throws Exception {
         scopedCredential.getServiceAccountPrivateKey());
   }
 
+  public void testCreateScopesNotSet() throws Exception {
+    final String serviceAccountEmail =
+        "36680232662-vrd7ji19q3ne0ah2csanun6bnr@developer.gserviceaccount.com";
+    final String accessToken = "1/MkSJoj1xsli0AccessToken_NKPY2";
+    MockTokenServerTransport transport = new MockTokenServerTransport();
+    transport.addServiceAccount(serviceAccountEmail, accessToken);
+
+    GoogleCredential credential = new GoogleCredential.Builder()
+        .setServiceAccountId(serviceAccountEmail)
+        .setServiceAccountPrivateKey(SecurityTestUtils.newRsaPrivateKey())
+        .setTransport(transport)
+        .setJsonFactory(JSON_FACTORY)
+        .build();
+    // Note that setServiceAccountScopes() is not called, so it is uninitialized (i.e. null) on the
+    // builder.
+    assertTrue(credential.getServiceAccountScopes().isEmpty());
+  }
+
   public void testGetApplicationDefaultNullTransportThrows() throws IOException {
     try {
       GoogleCredential.getApplicationDefault(null, JSON_FACTORY);
