CTTY commented on code in PR #1735: URL: https://github.com/apache/iceberg-rust/pull/1735#discussion_r2430346145
########## crates/iceberg/src/writer/partitioning/clustered_writer.rs: ########## @@ -0,0 +1,623 @@ +// 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. + +//! This module provides the `ClusteredWriter` implementation. + +use std::collections::HashSet; +use std::marker::PhantomData; + +use async_trait::async_trait; + +use crate::spec::{PartitionKey, Struct}; +use crate::writer::partitioning::PartitioningWriter; +use crate::writer::{DefaultInput, DefaultOutput, IcebergWriter, IcebergWriterBuilder}; +use crate::{Error, ErrorKind, Result}; + +/// A writer that writes data to a single partition at a time. +/// +/// This writer expects input data to be sorted by partition key. It maintains only one +/// active writer at a time, making it memory efficient for sorted data. +/// +/// # Type Parameters +/// +/// * `B` - The inner writer builder type +/// * `I` - Input type (defaults to `RecordBatch`) +/// * `O` - Output collection type (defaults to `Vec<DataFile>`) +#[derive(Clone)] +pub struct ClusteredWriter<B, I = DefaultInput, O = DefaultOutput> +where + B: IcebergWriterBuilder<I, O>, + O: IntoIterator + FromIterator<<O as IntoIterator>::Item>, + <O as IntoIterator>::Item: Clone, +{ + inner_builder: B, + current_writer: Option<B::R>, + current_partition: Option<Struct>, + closed_partitions: HashSet<Struct>, + output: Vec<<O as IntoIterator>::Item>, + _phantom: PhantomData<I>, +} + +impl<B, I, O> ClusteredWriter<B, I, O> +where + B: IcebergWriterBuilder<I, O>, + I: Send + 'static, + O: IntoIterator + FromIterator<<O as IntoIterator>::Item>, + <O as IntoIterator>::Item: Send + Clone, +{ + /// Create a new `ClusteredWriter`. + pub fn new(inner_builder: B) -> Self { + Self { + inner_builder, + current_writer: None, + current_partition: None, + closed_partitions: HashSet::new(), + output: Vec::new(), + _phantom: PhantomData, + } + } + + /// Closes the current writer if it exists, flushes the written data to output, and record closed partition. + async fn close_current_writer(&mut self) -> Result<()> { + if let Some(mut writer) = self.current_writer.take() { + self.output.extend(writer.close().await?); + + // Add the current partition to the set of closed partitions + if let Some(current_partition) = self.current_partition.take() { + self.closed_partitions.insert(current_partition); + } + } + + Ok(()) + } +} + +#[async_trait] +impl<B, I, O> PartitioningWriter<I, O> for ClusteredWriter<B, I, O> +where + B: IcebergWriterBuilder<I, O>, + I: Send + 'static, + O: IntoIterator + FromIterator<<O as IntoIterator>::Item> + Send + 'static, + <O as IntoIterator>::Item: Send + Clone, +{ + async fn write(&mut self, partition_key: Option<PartitionKey>, input: I) -> Result<()> { + if let Some(partition_key) = partition_key { + let partition_value = partition_key.data(); + + // Check if this partition has been closed already + if self.closed_partitions.contains(partition_value) { Review Comment: I was referring to [Java's behavior](https://github.com/apache/iceberg/blob/7938403a437f81a502fd82053dccff10a1531ada/core/src/main/java/org/apache/iceberg/io/ClusteredWriter.java#L93-L97) when writing this. When looking at the original java [PR](https://github.com/apache/iceberg/blob/7938403a437f81a502fd82053dccff10a1531ada/core/src/main/java/org/apache/iceberg/io/ClusteredWriter.java#L93-L97) I don't see any explicit explanation, but I think this can force users to be aware of if their data source is sorted and help identify hidden performance issues -- 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]
