Make nip.io usage resilient against lookup failures (#6885)

nip.io's "magic" DNS names are not always resolvable, or resolvable in every setup.
This change first tries to resolve the "magic" nip.io address and falls back to the pre-#6856 behavior if the pre-check fails.

testing/s3minio/src/main/java/org/projectnessie/minio/MinioContainer.java

@@ -16,13 +16,16 @@
 package org.projectnessie.minio;
 
 import com.google.common.base.Preconditions;
+import java.net.InetAddress;
 import java.net.URI;
+import java.net.UnknownHostException;
 import java.time.Duration;
 import java.util.HashMap;
 import java.util.Locale;
 import java.util.Map;
 import org.apache.hadoop.conf.Configuration;
 import org.junit.jupiter.api.extension.ExtensionContext.Store.CloseableResource;
+import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.testcontainers.containers.GenericContainer;
 import org.testcontainers.containers.output.Slf4jLogConsumer;
@@ -37,6 +40,8 @@
 final class MinioContainer extends GenericContainer<MinioContainer>
     implements MinioAccess, CloseableResource {
 
+  private static final Logger LOGGER = LoggerFactory.getLogger(MinioContainer.class);
+
   private static final int DEFAULT_PORT = 9000;
   private static final String DEFAULT_IMAGE = "quay.io/minio/minio";
   private static final String DEFAULT_TAG = "latest";
@@ -47,8 +52,28 @@ final class MinioContainer extends GenericContainer<MinioContainer>
 
   private static final String DEFAULT_STORAGE_DIRECTORY = "/data";
   private static final String HEALTH_ENDPOINT = "/minio/health/ready";
+  private static final String MINIO_DOMAIN_NAME;
   private static final String MINIO_DOMAIN_NIP = "minio.127-0-0-1.nip.io";
 
+  static boolean canRunOnMacOs() {
+    return MINIO_DOMAIN_NAME.equals(MINIO_DOMAIN_NIP);
+  }
+
+  static {
+    String name;
+    try {
+      InetAddress.getByName(MINIO_DOMAIN_NIP);
+      name = MINIO_DOMAIN_NIP;
+    } catch (UnknownHostException e) {
+      LOGGER.warn(
+          "Could not resolve '{}', falling back to 'localhost'. "
+              + "This usually happens when your router or DNS provider is unable to resolve the nip.io addresses.",
+          MINIO_DOMAIN_NIP);
+      name = "localhost";
+    }
+    MINIO_DOMAIN_NAME = name;
+  }
+
   private final String accessKey;
   private final String secretKey;
   private final String bucket;
@@ -75,7 +100,7 @@ public MinioContainer(String image, String accessKey, String secretKey, String b
     withEnv(MINIO_ACCESS_KEY, this.accessKey);
     withEnv(MINIO_SECRET_KEY, this.secretKey);
     // S3 SDK encodes bucket names in host names - need to tell Minio which domain to use
-    withEnv(MINIO_DOMAIN, MINIO_DOMAIN_NIP);
+    withEnv(MINIO_DOMAIN, MINIO_DOMAIN_NAME);
     withCommand("server", DEFAULT_STORAGE_DIRECTORY);
     setWaitStrategy(
         new HttpWaitStrategy()
@@ -150,7 +175,7 @@ public URI s3BucketUri(String path) {
   public void start() {
     super.start();
 
-    this.hostPort = MINIO_DOMAIN_NIP + ":" + getMappedPort(DEFAULT_PORT);
+    this.hostPort = MINIO_DOMAIN_NAME + ":" + getMappedPort(DEFAULT_PORT);
     this.s3endpoint = String.format("http://%s/", hostPort);
     this.bucketBaseUri = URI.create(String.format("s3://%s/", bucket()));
 

testing/s3minio/src/main/java/org/projectnessie/minio/MinioExtension.java

@@ -51,7 +51,9 @@ public ConditionEvaluationResult evaluateExecutionCondition(ExtensionContext con
     if (OS.current() == OS.LINUX) {
       return enabled("Running on Linux");
     }
-    if (OS.current() == OS.MAC && System.getenv("CI_MAC") == null) {
+    if (OS.current() == OS.MAC
+        && System.getenv("CI_MAC") == null
+        && MinioContainer.canRunOnMacOs()) {
       // Disable tests on GitHub Actions
       return enabled("Running on macOS locally");
     }