Fix #1495 - Avoid NPE in RuleBuilder

hapi-fhir-server/src/main/java/ca/uhn/fhir/rest/server/interceptor/auth/RuleBuilder.java

@@ -107,11 +107,12 @@ public class RuleBuilder implements IAuthRuleBuilder {
 
 	private class RuleBuilderFinished implements IAuthRuleFinished, IAuthRuleBuilderRuleOpClassifierFinished, IAuthRuleBuilderRuleOpClassifierFinishedWithTenantId {
 
-		private final BaseRule myOpRule;
+		protected final BaseRule myOpRule;
 		ITenantApplicabilityChecker myTenantApplicabilityChecker;
 		private List<IAuthRuleTester> myTesters;
 
 		RuleBuilderFinished(BaseRule theRule) {
+			assert theRule != null;
 			myOpRule = theRule;
 		}
 
@@ -291,12 +292,12 @@ public class RuleBuilder implements IAuthRuleBuilder {
 			public class RuleBuilderRuleConditionalClassifier extends RuleBuilderFinished implements IAuthRuleBuilderRuleConditionalClassifier {
 
 				RuleBuilderRuleConditionalClassifier() {
-					super(null);
+					super(new RuleImplConditional(myRuleName));
 				}
 
 				@Override
 				protected void doBuildRule() {
-					RuleImplConditional rule = new RuleImplConditional(myRuleName);
+					RuleImplConditional rule = (RuleImplConditional) myOpRule;
 					rule.setMode(myRuleMode);
 					rule.setOperationType(myOperationType);
 					rule.setAppliesTo(myAppliesTo);

hapi-fhir-server/src/test/java/ca/uhn/fhir/rest/server/interceptor/auth/RuleBuilderTest.java

@@ -9,6 +9,7 @@ import java.util.List;
 import static org.hamcrest.Matchers.contains;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.mock;
 
 public class RuleBuilderTest {
 
@@ -48,4 +49,11 @@ public class RuleBuilderTest {
 		));
 	}
 
+	@Test
+	public void testNullConditional() {
+		IAuthRuleBuilder ruleBuilder = new RuleBuilder().allow().metadata().andThen();
+		IAuthRuleTester writeAccessTester = mock(IAuthRuleTester.class);
+		ruleBuilder.allow().createConditional().resourcesOfType("anystring").withTester(writeAccessTester).andThen();
+	}
+
 }

src/changes/changes.xml

@@ -165,6 +165,10 @@
 				The Testpage Overlay has been upgraded to use FontAwesome 5.x, and now supports being
 				deployed to a servlet path other than "/".
 			</action>
+			<action type="fix" issue="1495">
+				A NullPointerException when using the AuthorizationInterceptor RuleBuilder to build a conditional
+				rule with a custom tester has been corrected. Thanks to Tue Toft Nørgård for reporting!
+			</action>
 		</release>
 		<release version="4.0.3" date="2019-09-03" description="Igloo (Point Release)">
 			<action type="fix">