seddonm1 commented on a change in pull request #8982: URL: https://github.com/apache/arrow/pull/8982#discussion_r547483460
########## File path: rust/datafusion/src/physical_plan/repartition.rs ########## @@ -0,0 +1,332 @@ +// 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. + +//! The repartition operator maps N input partitions to M output partitions based on a +//! partitioning scheme. + +use std::any::Any; +use std::pin::Pin; +use std::sync::Arc; +use std::task::{Context, Poll}; + +use crate::error::{DataFusionError, Result}; +use crate::physical_plan::{ExecutionPlan, Partitioning}; +use arrow::datatypes::SchemaRef; +use arrow::error::Result as ArrowResult; +use arrow::record_batch::RecordBatch; + +use super::{RecordBatchStream, SendableRecordBatchStream}; +use async_trait::async_trait; + +use crossbeam::channel::{unbounded, Receiver, Sender}; +use futures::stream::Stream; +use futures::StreamExt; +use tokio::sync::Mutex; +use tokio::task::JoinHandle; + +/// partition. No guarantees are made about the order of the resulting partition. +#[derive(Debug)] +pub struct RepartitionExec { + /// Input execution plan + input: Arc<dyn ExecutionPlan>, + /// Partitioning scheme to use + partitioning: Partitioning, + /// Receivers for output batches + rx: Arc<Mutex<Vec<Receiver<Option<ArrowResult<RecordBatch>>>>>>, + /// Senders for output batches + tx: Arc<Mutex<Vec<Sender<Option<ArrowResult<RecordBatch>>>>>>, +} + +#[async_trait] +impl ExecutionPlan for RepartitionExec { + /// Return a reference to Any that can be used for downcasting + fn as_any(&self) -> &dyn Any { + self + } + + /// Get the schema for this execution plan + fn schema(&self) -> SchemaRef { + self.input.schema() + } + + fn children(&self) -> Vec<Arc<dyn ExecutionPlan>> { + vec![self.input.clone()] + } + + fn with_new_children( + &self, + children: Vec<Arc<dyn ExecutionPlan>>, + ) -> Result<Arc<dyn ExecutionPlan>> { + match children.len() { + 1 => Ok(Arc::new(RepartitionExec::try_new( + children[0].clone(), + self.partitioning.clone(), + )?)), + _ => Err(DataFusionError::Internal( + "RepartitionExec wrong number of children".to_string(), + )), + } + } + + fn output_partitioning(&self) -> Partitioning { + self.partitioning.clone() + } + + async fn execute(&self, partition: usize) -> Result<SendableRecordBatchStream> { + // lock mutexes + let mut tx = self.tx.lock().await; + let mut rx = self.rx.lock().await; + + let num_input_partitions = self.input.output_partitioning().partition_count(); + let num_output_partition = self.partitioning.partition_count(); Review comment: Bikeshedding but `num_output_partition` -> `num_output_partitions` would help readability ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected]
