test(tdg): await data model readiness in TDGClientTest

TDGClientTest queried spaces right after cluster.start(), which only waits for the containers to come up. The TDG data model (and therefore the User/person spaces) is applied asynchronously afterwards, so on slower runners the first queries hit a not-yet-created space and failed with "attempt to index ... 'space' (a nil value)". Wait for the model in @BeforeAll by probing both spaces via retryUntilSuccess before the tests run.

Author: MaxSiominDev

tarantool-client/src/test/java/io/tarantool/client/integration/tdg/TDGClientTest.java

@@ -16,12 +16,14 @@
 import java.util.Objects;
 import java.util.UUID;
 import java.util.concurrent.CompletionException;
+import java.util.concurrent.TimeUnit;
 
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
+import org.rnorth.ducttape.unreliables.Unreliables;
 import org.testcontainers.containers.tdg.cluster.TDGCluster;
 import org.testcontainers.containers.tdg.cluster.TDGClusterImpl;
 import org.testcontainers.containers.tdg.configuration.TDGConfigurator;
@@ -41,6 +43,9 @@ class TDGClientTest {
       DockerImageName.parse(
           System.getenv().getOrDefault("TARANTOOL_REGISTRY", "") + "tdg2:2.11.5-0-geff8adb3");
 
+  /** Upper bound for the TDG data model to be applied cluster-wide after the containers start. */
+  private static final int MODEL_READINESS_TIMEOUT_SECONDS = 60;
+
   private static final Path ROOT_CONFIG_PATH;
 
   private static final TDGConfigurator configurator;
@@ -73,6 +78,24 @@ static void setUp() throws Exception {
             .withHost(configurator.core().getValue().iprotoMappedAddress().getHostName())
             .withPort(configurator.core().getValue().iprotoMappedAddress().getPort())
             .build();
+    awaitModelReady();
+  }
+
+  /**
+   * Waits until the TDG data model is applied cluster-wide. {@link TDGCluster#start()} only blocks
+   * until the containers are up, whereas the model (and therefore the spaces) is loaded
+   * asynchronously afterwards. Without this wait the first queries may hit a not-yet-created space
+   * and fail with "attempt to index ... 'space' (a nil value)" on slower runners.
+   */
+  private static void awaitModelReady() {
+    Unreliables.retryUntilSuccess(
+        MODEL_READINESS_TIMEOUT_SECONDS,
+        TimeUnit.SECONDS,
+        () -> {
+          client.space("User").get(1).join();
+          client.space("person").get(1).join();
+          return null;
+        });
   }
 
   @AfterAll