wForget commented on code in PR #4459: URL: https://github.com/apache/datafusion-comet/pull/4459#discussion_r3732907958
########## spark/src/main/scala/org/apache/comet/udf/CometRustUDF.scala: ########## @@ -0,0 +1,150 @@ +/* + * 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.udf + +import scala.util.Try + +import org.apache.spark.sql.SparkSession +import org.apache.spark.sql.expressions.UserDefinedFunction +import org.apache.spark.sql.functions.udf +import org.apache.spark.sql.types.DataType + +import com.fasterxml.jackson.databind.ObjectMapper +import com.fasterxml.jackson.databind.node.ObjectNode + +/** + * Entry point for registering Rust scalar UDFs with Comet. + * + * The UDF cdylib is built against the `comet-udf-sdk` crate and exposes its functions through an + * ABI built only on the Arrow C Data Interface, so a compiled UDF is not tied to Comet's + * DataFusion version. + * + * This is an experimental API. It is deliberately not annotated + * `org.apache.comet.annotation.Public`, so it sits outside the enumerated public API in Comet's + * [[https://datafusion.apache.org/comet/about/versioning_policy.html versioning policy]] and + * carries no compatibility guarantee: it may change or be removed in any release, including a + * patch release, with no deprecation cycle. + */ +object CometRustUDF { + + private val mapper: ObjectMapper = new ObjectMapper() + + /** + * Register a single Rust UDF with an explicit signature. + * + * Validates the library on the driver (loads it, confirms a UDF named `name` exists). On + * success a stub Spark catalog UDF is installed (so SQL/DataFrame name resolution succeeds) and + * the driver-side registry is updated. + * + * Executors do not consult the driver's registry: the library path travels with the plan in the + * `RustUdfCall` proto, and each executor loads the library itself on first use. The path must + * therefore be valid on every executor, not just the driver. + * + * `deterministic` must be `true`. Comet plans every imported kernel as immutable, so a + * nondeterministic UDF cannot yet be expressed; passing `false` fails here rather than silently + * planning the function as pure. + */ + def register( Review Comment: Can `inputTypes/returnType/deterministic` be obtained directly from the native side, or should we also validate it? -- 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]
