marvinlanhenke commented on code in PR #324: URL: https://github.com/apache/iceberg-rust/pull/324#discussion_r1582083814
########## crates/integrations/datafusion/src/physical_plan/scan.rs: ########## @@ -0,0 +1,123 @@ +// 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. + +use std::{any::Any, pin::Pin, sync::Arc}; + +use datafusion::{ + arrow::{array::RecordBatch, datatypes::SchemaRef as ArrowSchemaRef}, + execution::{SendableRecordBatchStream, TaskContext}, + physical_expr::EquivalenceProperties, + physical_plan::{ + stream::RecordBatchStreamAdapter, DisplayAs, ExecutionMode, ExecutionPlan, Partitioning, + PlanProperties, + }, +}; +use futures::{Stream, TryStreamExt}; +use iceberg::table::Table; + +use crate::to_datafusion_error; + +#[derive(Debug)] +pub(crate) struct IcebergTableScan { + table: Table, + schema: ArrowSchemaRef, + plan_properties: PlanProperties, +} + +impl IcebergTableScan { + pub(crate) fn new(table: Table, schema: ArrowSchemaRef) -> Self { + let plan_properties = Self::compute_properties(schema.clone()); + + Self { + table, + schema, + plan_properties, + } + } + + fn compute_properties(schema: ArrowSchemaRef) -> PlanProperties { + // TODO: + // This is more or less a placeholder, to be replaced + // once we support output-partitioning + PlanProperties::new( + EquivalenceProperties::new(schema), + Partitioning::UnknownPartitioning(1), + ExecutionMode::Bounded, + ) + } +} + +impl ExecutionPlan for IcebergTableScan { + fn as_any(&self) -> &dyn Any { + self + } + + fn children(&self) -> Vec<Arc<dyn ExecutionPlan>> { + vec![] + } + + fn with_new_children( + self: Arc<Self>, + _children: Vec<Arc<dyn ExecutionPlan>>, + ) -> datafusion::error::Result<Arc<dyn ExecutionPlan>> { + Ok(self) + } + + fn properties(&self) -> &PlanProperties { + &self.plan_properties + } + + fn execute( + &self, + _partition: usize, + _context: Arc<TaskContext>, + ) -> datafusion::error::Result<SendableRecordBatchStream> { + let fut = get_batch_stream(self.table.clone()); + let stream = futures::stream::once(fut).try_flatten(); + + Ok(Box::pin(RecordBatchStreamAdapter::new( + self.schema.clone(), + stream, + ))) + } +} + +impl DisplayAs for IcebergTableScan { + fn fmt_as( + &self, + _t: datafusion::physical_plan::DisplayFormatType, + f: &mut std::fmt::Formatter, + ) -> std::fmt::Result { + write!(f, "IcebergTableScan") + } +} + +async fn get_batch_stream( + table: Table, +) -> datafusion::error::Result< + Pin<Box<dyn Stream<Item = datafusion::error::Result<RecordBatch>> + Send>>, +> { + let table_scan = table.scan().build().map_err(to_datafusion_error)?; + + let stream = table_scan + .to_arrow() + .await + .map_err(to_datafusion_error)? + .map_err(to_datafusion_error); Review Comment: @liurenjie1024 @ZENOTME @viirya I had no idea how to solve this better; but it still looks weird and redundant. Why do I need to do this? First `map_err` unwraps the result from `to_arrow()` and the second `map_err` converts the outer result (wrapping the boxed stream) into a `datafusion::error:Result` which is required by `futures::stream::once(fut).try_flatten()`. -- 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: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
