tustvold commented on code in PR #8021: URL: https://github.com/apache/arrow-datafusion/pull/8021#discussion_r1394323206
########## datafusion/core/src/datasource/stream.rs: ########## @@ -0,0 +1,326 @@ +// 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. + +//! TableProvider for stream sources, such as FIFO files + +use std::any::Any; +use std::fmt::Formatter; +use std::fs::{File, OpenOptions}; +use std::io::BufReader; +use std::path::PathBuf; +use std::str::FromStr; +use std::sync::Arc; + +use arrow_array::{RecordBatch, RecordBatchReader, RecordBatchWriter}; +use arrow_schema::SchemaRef; +use async_trait::async_trait; +use futures::StreamExt; +use tokio::task::spawn_blocking; + +use datafusion_common::{plan_err, DataFusionError, Result}; +use datafusion_execution::{SendableRecordBatchStream, TaskContext}; +use datafusion_expr::{CreateExternalTable, Expr, TableType}; +use datafusion_physical_plan::common::AbortOnDropSingle; +use datafusion_physical_plan::insert::{DataSink, FileSinkExec}; +use datafusion_physical_plan::metrics::MetricsSet; +use datafusion_physical_plan::stream::RecordBatchReceiverStreamBuilder; +use datafusion_physical_plan::streaming::{PartitionStream, StreamingTableExec}; +use datafusion_physical_plan::{DisplayAs, DisplayFormatType, ExecutionPlan}; + +use crate::datasource::provider::TableProviderFactory; +use crate::datasource::{create_ordering, TableProvider}; +use crate::execution::context::SessionState; + +/// A [`TableProviderFactory`] for [`StreamTable`] +#[derive(Debug, Default)] +pub struct StreamTableFactory {} + +#[async_trait] +impl TableProviderFactory for StreamTableFactory { + async fn create( + &self, + state: &SessionState, + cmd: &CreateExternalTable, + ) -> Result<Arc<dyn TableProvider>> { + let schema: SchemaRef = Arc::new(cmd.schema.as_ref().into()); + let location = cmd.location.clone(); + let encoding = cmd.file_type.parse()?; + + let config = StreamConfig::new_file(schema, location.into()) + .with_encoding(encoding) + .with_order(cmd.order_exprs.clone()) + .with_header(cmd.has_header) + .with_batch_size(state.config().batch_size()); + + Ok(Arc::new(StreamTable(Arc::new(config)))) + } +} + +/// The data encoding for [`StreamTable`] +#[derive(Debug, Clone)] +pub enum StreamEncoding { + /// CSV records + Csv, + /// Newline-delimited JSON records + Json, +} + +impl FromStr for StreamEncoding { + type Err = DataFusionError; + + fn from_str(s: &str) -> std::result::Result<Self, Self::Err> { + match s.to_ascii_lowercase().as_str() { + "csv" => Ok(Self::Csv), + "json" => Ok(Self::Json), + _ => plan_err!("Unrecognised StreamEncoding {}", s), + } + } +} + +/// The configuration for a [`StreamTable`] +#[derive(Debug)] +pub struct StreamConfig { Review Comment: I'm not sure this would necessarily change materially, it parallels ListingTableConfig which is used by ListingTable, but I suppose we shall see -- 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]
