Xuanwo commented on code in PR #2903: URL: https://github.com/apache/incubator-opendal/pull/2903#discussion_r1301367728
########## core/src/raw/oio/write/at_least_buf_write.rs: ########## @@ -0,0 +1,127 @@ +// 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 crate::raw::oio::{StreamExt, Streamer}; +use crate::raw::*; +use crate::*; +use async_trait::async_trait; +use bytes::Bytes; + +/// AtLeastBufWrite is used to implement [`Write`] based on at least buffer. +/// +/// Users can wrap a writer and a buffer together. +pub struct AtLeastBufWriter<W: oio::Write> { + inner: W, + + /// The total size of the data. + /// + /// If the total size is known, we will write to underlying storage directly without buffer it + /// when possible. + total_size: Option<u64>, + + /// The size for buffer, we will flush the underlying storage if the buffer is full. + buffer_size: usize, + buffer: oio::ChunkedCursor, +} + +impl<W: oio::Write> AtLeastBufWriter<W> { + /// Create a new at least buf writer. + pub fn new(inner: W, buffer_size: usize) -> Self { + Self { + inner, + total_size: None, + buffer_size, + buffer: oio::ChunkedCursor::new(), + } + } + + /// Configure the total size for writer. + pub fn with_total_size(mut self, total_size: Option<u64>) -> Self { + self.total_size = total_size; + self + } +} + +#[async_trait] +impl<W: oio::Write> oio::Write for AtLeastBufWriter<W> { + async fn write(&mut self, bs: Bytes) -> Result<()> { + // If total size is known and equals to given bytes, we can write it directly. + if let Some(total_size) = self.total_size { + if total_size == bs.len() as u64 { + return self.inner.write(bs).await; + } + } + + // Push the bytes into the buffer if the buffer is not full. + if self.buffer.len() + bs.len() <= self.buffer_size { + self.buffer.push(bs); + return Ok(()); + } + + let mut buf = self.buffer.clone(); + buf.push(bs); + + self.inner + .sink(buf.len() as u64, Box::new(buf)) Review Comment: It's required to implement sink after this pr. -- 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]
