fix(QTDI-2954): fix possible NPE in VaultClient

vault-client/src/main/java/org/talend/sdk/components/vault/client/VaultClient.java

@@ -474,8 +474,8 @@ private void throwError(final Throwable cause) {
         if (WebApplicationException.class.isInstance(cause)) {
             final WebApplicationException wae = WebApplicationException.class.cast(cause);
             final Response response = wae.getResponse();
-            status = response.getStatus();
             if (response != null) {
+                status = response.getStatus();
                 if (ErrorPayload.class.isInstance(response.getEntity())) { // internal error
                     throw wae;
                 } else {

vault-client/src/test/java/org/talend/sdk/components/vault/client/VaultClientTest.java

@@ -19,12 +19,15 @@
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
 import java.util.HashMap;
 import java.util.Map;
 
 import javax.enterprise.inject.se.SeContainer;
 import javax.enterprise.inject.se.SeContainerInitializer;
 import javax.inject.Inject;
+import javax.ws.rs.WebApplicationException;
 import javax.ws.rs.client.Client;
 import javax.ws.rs.client.Entity;
 import javax.ws.rs.client.WebTarget;
@@ -296,6 +299,37 @@
                 response.readEntity(ErrorPayload.class).getDescription());
     }
 
+    @Test
+    void throwErrorWithNullResponseDoesNotNpe() throws Exception {
+        // A WebApplicationException whose getResponse() returns null must not trigger an NPE
+        // in throwError(Throwable); the default cantDecipherStatusCode should be used instead.
+        final int defaultStatus = 422;
+        // Use a fresh VaultClient instance (not the CDI proxy) so reflective field access works.
+        final VaultClient client = new VaultClient();
+        client.setCantDecipherStatusCode(defaultStatus);
+        final WebApplicationException waeWithoutResponse = new WebApplicationException("boom") {
+
+            @Override
+            public Response getResponse() {
+                return null;
+            }
+        };
+
+        final Method throwError = VaultClient.class.getDeclaredMethod("throwError", Throwable.class);
+        throwError.setAccessible(true);
+        try {
+            throwError.invoke(client, waeWithoutResponse);
+            org.junit.jupiter.api.Assertions.fail("Expected a WebApplicationException to be thrown");
+        } catch (final InvocationTargetException ite) {
+            final Throwable target = ite.getTargetException();
+            assertTrue(target instanceof WebApplicationException,
+                    "Expected WebApplicationException, got " + target);
+            final WebApplicationException thrown = (WebApplicationException) target;
+            assertEquals(defaultStatus, thrown.getResponse().getStatus());
+            assertEquals("boom", thrown.getMessage());
+        }
+    }
+
     /**
      * Demonstration purpose: with a "real" vault server instance
      *