SNOW-3344317 normalize S3 client URI scheme before attempting endpointOverride

Author: sfc-gh-dszmolka

src/main/java/net/snowflake/client/internal/jdbc/cloud/storage/SnowflakeS3Client.java

@@ -178,7 +178,7 @@ private void setupSnowflakeS3Client(
       if (!endpointForOverride.startsWith("https://")
           && !endpointForOverride.startsWith("http://")) {
         logger.debug(
-            "SNOW-3344317: stageEndPoint has no scheme: {}", this.stageEndPoint);
+            "AWS S3 Client: stage endpoint {} has no scheme, normalizing for URI creation.", this.stageEndPoint);
         endpointForOverride = "https://" + endpointForOverride;
       }
       clientBuilder.endpointOverride(URI.create(endpointForOverride));

src/test/java/net/snowflake/client/internal/jdbc/cloud/storage/SnowflakeS3ClientTest.java

@@ -1,9 +1,25 @@
 package net.snowflake.client.internal.jdbc.cloud.storage;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import java.lang.reflect.Field;
+import java.net.URI;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Optional;
+import net.snowflake.client.api.exception.SnowflakeSQLException;
 import org.junit.jupiter.api.Test;
+import software.amazon.awssdk.services.s3.S3AsyncClient;
 
+/**
+ * Unit tests for {@link SnowflakeS3Client} endpoint selection (GS {@code stageInfo.endPoint} and
+ * regional URL mode). Uses {@link S3AsyncClient#serviceClientConfiguration()}{@code
+ * .endpointOverride()} to read the effective override.
+ */
 public class SnowflakeS3ClientTest {
 
   @Test
@@ -14,4 +30,153 @@ public void shouldDetermineDomainForRegion() {
     assertEquals(
         "amazonaws.com.cn", SnowflakeS3Client.getDomainSuffixForRegionalUrl("CN-NORTHWEST-1"));
   }
+
+  /** Documents why bare hostnames must be normalized before {@code endpointOverride(URI)}. */
+  @Test
+  public void uriCreate_bareAwsHostname_hasNullScheme() {
+    assertNull(URI.create("s3.us-west-2.amazonaws.com").getScheme());
+  }
+
+  @Test
+  public void endpointOverride_stageEndPointWithoutScheme_prependsHttps() throws Exception {
+    SnowflakeS3Client client =
+        newClient(
+            "eu-west-1",
+            "s3.eu-west-1.amazonaws.com",
+            false,
+            /* isClientSideEncrypted */ false);
+    try {
+      URI override = endpointOverride(client).orElseThrow();
+      assertEquals("https", override.getScheme());
+      assertEquals("s3.eu-west-1.amazonaws.com", override.getHost());
+    } finally {
+      client.shutdown();
+    }
+  }
+
+  @Test
+  public void endpointOverride_stageEndPointWithHttps_unchanged() throws Exception {
+    String url = "https://s3-fips.us-gov-west-1.amazonaws.com";
+    SnowflakeS3Client client =
+        newClient("us-gov-west-1", url, false, /* isClientSideEncrypted */ false);
+    try {
+      URI override = endpointOverride(client).orElseThrow();
+      assertEquals(URI.create(url), override);
+    } finally {
+      client.shutdown();
+    }
+  }
+
+  @Test
+  public void endpointOverride_stageEndPointWithHttp_unchanged() throws Exception {
+    String url = "http://minio.local:9000";
+    SnowflakeS3Client client =
+        newClient("us-east-1", url, false, /* isClientSideEncrypted */ false);
+    try {
+      URI override = endpointOverride(client).orElseThrow();
+      assertEquals("http", override.getScheme());
+      assertEquals("minio.local", override.getHost());
+      assertEquals(9000, override.getPort());
+    } finally {
+      client.shutdown();
+    }
+  }
+
+  @Test
+  public void endpointOverride_useS3RegionalUrl_commercialRegion() throws Exception {
+    SnowflakeS3Client client =
+        newClient(
+            "us-west-2",
+            /* stageEndPoint */ null,
+            /* useS3RegionalUrl */ true,
+            /* isClientSideEncrypted */ false);
+    try {
+      URI override = endpointOverride(client).orElseThrow();
+      assertEquals(URI.create("https://s3.us-west-2.amazonaws.com"), override);
+    } finally {
+      client.shutdown();
+    }
+  }
+
+  @Test
+  public void endpointOverride_useS3RegionalUrl_chinaRegion() throws Exception {
+    SnowflakeS3Client client =
+        newClient(
+            "cn-northwest-1",
+            /* stageEndPoint */ null,
+            /* useS3RegionalUrl */ true,
+            /* isClientSideEncrypted */ false);
+    try {
+      URI override = endpointOverride(client).orElseThrow();
+      assertEquals(URI.create("https://s3.cn-northwest-1.amazonaws.com.cn"), override);
+    } finally {
+      client.shutdown();
+    }
+  }
+
+  @Test
+  public void endpointOverride_noStageEndPoint_noRegionalUrl_noOverride() throws Exception {
+    SnowflakeS3Client client =
+        newClient(
+            "eu-central-1",
+            /* stageEndPoint */ null,
+            /* useS3RegionalUrl */ false,
+            /* isClientSideEncrypted */ false);
+    try {
+      assertFalse(endpointOverride(client).isPresent());
+    } finally {
+      client.shutdown();
+    }
+  }
+
+  /** Regression: scheme-less {@code stageEndPoint} must not NPE inside AWS SDK v2 client build. */
+  @Test
+  public void constructor_schemeLessStageEndPoint_doesNotThrowNpe() throws Exception {
+    SnowflakeS3Client client = null;
+    try {
+      client =
+          newClient(
+              "us-west-2",
+              "s3.us-west-2.amazonaws.com",
+              false,
+              /* isClientSideEncrypted */ false);
+      assertNotNull(client);
+      assertTrue(endpointOverride(client).isPresent());
+      assertNotNull(endpointOverride(client).get().getScheme());
+    } finally {
+      if (client != null) {
+        client.shutdown();
+      }
+    }
+  }
+
+  private static SnowflakeS3Client newClient(
+      String stageRegion,
+      String stageEndPoint,
+      boolean useS3RegionalUrl,
+      boolean isClientSideEncrypted)
+      throws SnowflakeSQLException {
+    Map<String, String> creds = new HashMap<>();
+    creds.put("AWS_KEY_ID", "AKIA_TEST");
+    creds.put("AWS_SECRET_KEY", "testSecretAccessKey");
+    SnowflakeS3Client.ClientConfiguration config =
+        new SnowflakeS3Client.ClientConfiguration(2, 3, 5_000, 5_000);
+    return new SnowflakeS3Client(
+        creds,
+        config,
+        /* encMat */ null,
+        /* proxyProperties */ null,
+        stageRegion,
+        stageEndPoint,
+        isClientSideEncrypted,
+        /* session */ null,
+        useS3RegionalUrl);
+  }
+
+  private static Optional<URI> endpointOverride(SnowflakeS3Client client) throws Exception {
+    Field f = SnowflakeS3Client.class.getDeclaredField("amazonClient");
+    f.setAccessible(true);
+    S3AsyncClient aws = (S3AsyncClient) f.get(client);
+    return aws.serviceClientConfiguration().endpointOverride();
+  }
 }