mbutrovich commented on code in PR #4309: URL: https://github.com/apache/datafusion-comet/pull/4309#discussion_r3242718251
########## common/src/main/java/org/apache/comet/cloud/CometCloudCredentialDispatcher.java: ########## @@ -0,0 +1,176 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +package org.apache.comet.cloud; + +import java.util.ArrayList; +import java.util.List; +import java.util.ServiceLoader; +import java.util.stream.Collectors; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +// spotless:off +/* + * Architecture Overview: + * + * JVM Side | Native Side + * ┌──────────────────────────────────────────┐ | ┌──────────────────────────────────────────┐ + * │ CometCloudCredentialDispatcher │ | │ S3 Object Reading │ + * │ │ | │ │ + * │ ┌────────────────────────────────────┐ │ | │ ┌────────────────────────────────────┐ │ + * │ │ ServiceLoader discovery: │ │ | │ │ DataFusion iceberg-rust │ │ + * │ │ META-INF/services/ │ │ | │ │ object_store opendal │ │ + * │ │ o.a.c.cloud.CometCloudCred... │ │ | │ └────────────────────────────────────┘ │ + * │ └────────────────────────────────────┘ │ | │ │ │ │ + * │ │ │ | │ ▼ ▼ │ + * │ ▼ │ | │ ┌────────────────────────────────────┐ │ + * │ ┌────────────────────────────────────┐ │ | │ │ CometCredentialBridge (Rust) │ │ + * │ │ CometCloudCredentialProvider │ │ | │ │ impl object_store:: │ │ + * │ │ (single instance, cached) │ │ | │ │ CredentialProvider │ │ + * │ └────────────────────────────────────┘ │ | │ │ impl reqsign_core:: │ │ + * │ │ │ | │ │ ProvideCredential │ │ + * │ ▼ │ | │ └────────────────────────────────────┘ │ + * │ ┌────────────────────────────────────┐ │ | │ │ │ + * │ │ .getCredentialsForPath(...) │◄─┼───────┼─────┼──╗ ▼ │ + * │ └────────────────────────────────────┘ │ | │ ╔════════════════════════════════════╗ │ + * │ │ │ | │ ║ JNI CALL: ║ │ + * │ ▼ │ | │ ║ getCredentialsForPath( ║ │ + * │ ┌────────────────────────────────────┐ │ | │ ║ bucket, path, mode) ║ │ + * │ │ return CometCredentials POJO │──┼───────┼─────┼─►║ ║ │ + * │ │ (access key, secret, token, │ │ | │ ╚════════════════════════════════════╝ │ + * │ │ region, expiration) │ │ | │ │ │ + * │ └────────────────────────────────────┘ │ | │ ▼ │ + * │ │ | │ ┌────────────────────────────────────┐ │ + * │ │ | │ │ AwsCredential │ │ + * │ │ | │ │ used to sign S3 requests │ │ + * │ │ | │ └────────────────────────────────────┘ │ + * └──────────────────────────────────────────┘ | └──────────────────────────────────────────┘ + * | + * JNI Boundary + * + * Setup Phase (one-time per executor): + * 1. Vendor JAR ships an impl of CometCloudCredentialProvider via META-INF/services. + * 2. CometCloudCredentialDispatcher resolves it via ServiceLoader on first class-load. + * 3. Native side caches dispatcher class + static method ID in OnceCell. + * + * Runtime Phase (per S3 request): + * 4. object_store / opendal calls its async credential trait on CometCredentialBridge. + * 5. Bridge enters JNI, invokes dispatcher.getCredentialsForPath(bucket, path, mode). + * 6. Provider returns a CometCredentials POJO; vendor may call its own STS / authorization service. + * 7. Rust reads fields via JNI accessors, returns AwsCredential for request signing. + */ +// spotless:on + +/** + * Static entry point invoked from Comet's native code (via JNI) to fetch AWS credentials for an S3 + * request. + * + * <p>Resolution rules at first class-load: + * + * <ul> + * <li>Zero impls registered via {@code ServiceLoader} → {@link #isProviderRegistered()} returns + * false; native callers fall through to the existing AWS credential chain. + * <li>Exactly one impl registered → cached and used for every credential request. + * <li>Multiple impls registered → throws {@link IllegalStateException} at class-load, failing the + * executor loudly. Operators should remove all but one bridge jar. + * </ul> + * + * <p>Discovery is via classpath only; there is no Comet-specific config knob for selecting a + * provider. This keeps the credentials Comet uses identical to whatever the same JVM would use if a + * query fell back to Spark execution mid-flight. + */ +public final class CometCloudCredentialDispatcher { Review Comment: Yep, renamed already to `CometS3CredentialDispatcher`. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
