use super::{BlobReader, BlobService, BlobWriter}; use crate::{B3Digest, Error}; use std::{ io::{self, Cursor, Write}, path::PathBuf, task::Poll, }; use tonic::async_trait; use tracing::instrument; #[derive(Clone)] pub struct SledBlobService { db: sled::Db, } impl SledBlobService { pub fn new(p: PathBuf) -> Result<Self, sled::Error> { let config = sled::Config::default().use_compression(true).path(p); let db = config.open()?; Ok(Self { db }) } pub fn new_temporary() -> Result<Self, sled::Error> { let config = sled::Config::default().temporary(true); let db = config.open()?; Ok(Self { db }) } } #[async_trait] impl BlobService for SledBlobService { #[instrument(skip(self), fields(blob.digest=%digest))] async fn has(&self, digest: &B3Digest) -> Result<bool, Error> { match self.db.contains_key(digest.as_slice()) { Ok(has) => Ok(has), Err(e) => Err(Error::StorageError(e.to_string())), } } #[instrument(skip(self), fields(blob.digest=%digest))] async fn open_read(&self, digest: &B3Digest) -> Result<Option<Box<dyn BlobReader>>, Error> { match self.db.get(digest.as_slice()) { Ok(None) => Ok(None), Ok(Some(data)) => Ok(Some(Box::new(Cursor::new(data[..].to_vec())))), Err(e) => Err(Error::StorageError(e.to_string())), } } #[instrument(skip(self))] async fn open_write(&self) -> Box<dyn BlobWriter> { Box::new(SledBlobWriter::new(self.db.clone())) } } pub struct SledBlobWriter { db: sled::Db, /// Contains the buffer Vec and hasher, or None if already closed writers: Option<(Vec<u8>, blake3::Hasher)>, /// The digest that has been returned, if we successfully closed. digest: Option<B3Digest>, } impl SledBlobWriter { pub fn new(db: sled::Db) -> Self { Self { db, writers: Some((Vec::new(), blake3::Hasher::new())), digest: None, } } } impl tokio::io::AsyncWrite for SledBlobWriter { fn poll_write( mut self: std::pin::Pin<&mut Self>, _cx: &mut std::task::Context<'_>, b: &[u8], ) -> std::task::Poll<Result<usize, io::Error>> { Poll::Ready(match &mut self.writers { None => Err(io::Error::new( io::ErrorKind::NotConnected, "already closed", )), Some((ref mut buf, ref mut hasher)) => { let bytes_written = buf.write(b)?; hasher.write(&b[..bytes_written]) } }) } fn poll_flush( mut self: std::pin::Pin<&mut Self>, _cx: &mut std::task::Context<'_>, ) -> std::task::Poll<Result<(), io::Error>> { Poll::Ready(match &mut self.writers { None => Err(io::Error::new( io::ErrorKind::NotConnected, "already closed", )), Some(_) => Ok(()), }) } fn poll_shutdown( self: std::pin::Pin<&mut Self>, _cx: &mut std::task::Context<'_>, ) -> std::task::Poll<Result<(), io::Error>> { // shutdown is "instantaneous", we only write to a Vec<u8> as buffer. Poll::Ready(Ok(())) } } #[async_trait] impl BlobWriter for SledBlobWriter { async fn close(&mut self) -> Result<B3Digest, Error> { if self.writers.is_none() { match &self.digest { Some(digest) => Ok(digest.clone()), None => Err(crate::Error::StorageError( "previously closed with error".to_string(), )), } } else { let (buf, hasher) = self.writers.take().unwrap(); let digest: B3Digest = hasher.finalize().as_bytes().into(); // Only insert if the blob doesn't already exist. if !self.db.contains_key(digest.as_slice()).map_err(|e| { Error::StorageError(format!("Unable to check if we have blob {}: {}", digest, e)) })? { // put buf in there. This will move buf out. self.db .insert(digest.as_slice(), buf) .map_err(|e| Error::StorageError(format!("unable to insert blob: {}", e)))?; } self.digest = Some(digest.clone()); Ok(digest) } } }