feat(mater): remove filestore abstraction in favor of blockwriter (#773)

Author: jmg-duarte

mater/cli/src/convert.rs

@@ -1,6 +1,6 @@
 use std::path::PathBuf;
 
-use mater::{create_filestore, Cid, Config, Error};
+use mater::{Blockwriter, Cid, Error};
 use tokio::fs::File;
 
 /// Converts a file at location `input_path` to a CARv2 file at `output_path`
@@ -16,10 +16,10 @@ pub(crate) async fn convert_file_to_car(
     }?;
 
     if input_path.as_os_str() == "-" {
-        create_filestore(tokio::io::stdin(), output_file, Config::default()).await
+        Blockwriter::import(tokio::io::stdin(), output_file).await
     } else {
         let source_file = File::open(input_path).await?;
-        create_filestore(source_file, output_file, Config::default()).await
+        Blockwriter::import(source_file, output_file).await
     }
 }
 

mater/lib/benches/benchmark.rs

@@ -6,7 +6,7 @@ use std::{
 };
 
 use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion};
-use mater::{create_filestore, Blockwriter, Config};
+use mater::Blockwriter;
 use rand::{prelude::SliceRandom, rngs::ThreadRng, Rng};
 use tempfile::{tempdir, TempDir};
 use tokio::{
@@ -169,29 +169,27 @@ fn prepare_source_file(content: &[u8]) -> (TempDir, PathBuf) {
     (temp_dir, file)
 }
 
-/// Create a filestore. This function is benchmarked.
-async fn create_filestore_benched(source: &Path, target: &Path) {
+/// Import a source into a writer. This function is benchmarked.
+async fn blockwriter_import(source: &Path, target: &Path) {
     let source_file = File::open(source).await.unwrap();
     let output_file = File::create(target).await.unwrap();
 
-    create_filestore(source_file, output_file, Config::default())
-        .await
-        .unwrap();
+    Blockwriter::import(source_file, output_file).await.unwrap();
 }
 
-fn filestore(c: &mut Criterion) {
+fn import(c: &mut Criterion) {
     let files = get_source_files();
 
     for (params, source_file, temp_dir) in files {
         let target_file = temp_dir.path().join("target");
 
         c.bench_with_input(BenchmarkId::new("filestore", params), &(), |b, _: &()| {
             b.to_async(TokioExecutor::new().unwrap())
-                .iter(|| create_filestore_benched(&source_file, &target_file));
+                .iter(|| blockwriter_import(&source_file, &target_file));
         });
     }
 }
 
 criterion_group!(bench_reading, read_write);
-criterion_group!(bench_filestore, filestore);
-criterion_main!(bench_reading, bench_filestore);
+criterion_group!(bench_import, import);
+criterion_main!(bench_reading, bench_import);

mater/lib/src/file_reader.rs

@@ -178,18 +178,18 @@ mod test {
 
     #[tokio::test]
     async fn read_duplicated_blocks() {
-        let raw_input = tokio::fs::read("tests/fixtures/original/zero")
-            .await
-            .unwrap();
-
         let mut loader = CarExtractor::from_path("tests/fixtures/car_v2/zero.car")
             .await
             .unwrap();
         let root = loader.roots().await.unwrap()[0];
         let mut out_check = Cursor::new(vec![1u8; 4096]);
         loader.copy_tree(&root, &mut out_check).await.unwrap();
 
-        assert_eq!(raw_input, out_check.into_inner());
+        let expected = [0u8; 524288].as_slice();
+        let inner = out_check.into_inner();
+        let result = inner.as_slice();
+
+        assert_eq!(expected, result);
     }
 
     async fn load_and_compare<P1, P2>(original: P1, path: P2)

mater/lib/src/lib.rs

@@ -26,7 +26,7 @@ pub use cid::{CidExt, MultihashExt};
 pub use file_reader::CarExtractor;
 pub use ipld_core::cid::Cid;
 pub use multicodec::{DAG_PB_CODE, IDENTITY_CODE, RAW_CODE};
-pub use stores::{create_filestore, Blockwriter, Config, FileBlockstore};
+pub use stores::{Blockwriter, Config, FileBlockstore};
 pub use v1::{BlockMetadata, Header as CarV1Header, Reader as CarV1Reader, Writer as CarV1Writer};
 pub use v2::{
     verify_cid, Characteristics, Header as CarV2Header, Index, IndexEntry, IndexSorted,

mater/lib/src/stores/blockstore.rs

@@ -7,11 +7,10 @@ use futures::stream::StreamExt;
 use ipld_core::cid::Cid;
 use tokio::io::{AsyncRead, AsyncSeek, AsyncSeekExt, AsyncWrite};
 
-use super::{DEFAULT_BLOCK_SIZE, DEFAULT_TREE_WIDTH};
 use crate::{
     unixfs::stream_balanced_tree,
     v1::{self},
-    v2, BlockMetadata, Error, Index, IndexEntry, IndexSorted, SingleWidthIndex,
+    v2, BlockMetadata, Config, Error, Index, IndexEntry, IndexSorted, SingleWidthIndex,
 };
 
 /// CAR file writer.
@@ -20,6 +19,7 @@ pub struct Blockwriter<W> {
     index: HashMap<Cid, BlockMetadata>,
     roots: Vec<Cid>,
     started: bool,
+    config: Config,
 }
 
 impl<W> Blockwriter<W> {
@@ -30,6 +30,7 @@ impl<W> Blockwriter<W> {
             index: HashMap::new(),
             roots: Vec::with_capacity(1),
             started: false,
+            config: Default::default(),
         }
     }
 
@@ -66,6 +67,7 @@ impl Blockwriter<Cursor<Vec<u8>>> {
             index: HashMap::new(),
             roots: Vec::with_capacity(1),
             started: false,
+            config: Default::default(),
         }
     }
 }
@@ -74,6 +76,19 @@ impl<W> Blockwriter<W>
 where
     W: AsyncWrite + AsyncSeek + Unpin,
 {
+    /// Convert `source` into a CAR file, writing it to `writer`.
+    /// Returns the root [`Cid`].
+    pub async fn import<S>(source: S, writer: W) -> Result<Cid, Error>
+    where
+        S: AsyncRead + Unpin,
+    {
+        let mut writer = Self::new(writer);
+        writer.write_from(source).await?;
+        let root = *writer.roots.first().ok_or(Error::EmptyRootsError)?;
+        writer.finish().await?;
+        Ok(root)
+    }
+
     /// Writes the contents from `source`, adding a new root to [`Blockwriter`].
     pub async fn write_from<S>(&mut self, source: S) -> Result<(), Error>
     where
@@ -87,8 +102,15 @@ where
 
         let mut current_position = self.writer.get_inner_mut().stream_position().await?;
 
-        let chunker = crate::chunker::byte_stream_chunker(source, DEFAULT_BLOCK_SIZE);
-        let nodes = stream_balanced_tree(chunker, DEFAULT_TREE_WIDTH).peekable();
+        let nodes = match self.config {
+            Config::Balanced {
+                chunk_size,
+                tree_width,
+            } => {
+                let chunker = crate::chunker::byte_stream_chunker(source, chunk_size);
+                stream_balanced_tree(chunker, tree_width).peekable()
+            }
+        };
         tokio::pin!(nodes);
 
         let mut root = None;

mater/lib/src/stores/filestore.rs

@@ -1,10 +1,8 @@
 mod blockstore;
 mod file;
-mod filestore;
 
 pub use blockstore::Blockwriter;
 pub use file::FileBlockstore;
-pub use filestore::create_filestore;
 
 /// The default block size, as defined in
 /// [boxo](https://github.com/ipfs/boxo/blob/f4fe8997dcbeb39b3a4842d8f08b34739bfd84a4/chunker/parse.go#L13).

mater/lib/src/stores/mod.rs

@@ -404,7 +404,7 @@ where
     // Stream the body from source to the temp file.
     let file = File::create(&temp_file_path).await?;
     let writer = BufWriter::new(file);
-    let cid = mater::create_filestore(source, writer, mater::Config::default()).await?;
+    let cid = mater::Blockwriter::import(source, writer).await?;
     tracing::trace!("finished writing the CAR archive");
 
     // If the file is successfully written, we can now move it to the final