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refactor(tvix/store/blobsvc): make BlobStore async

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We previously kept the trait of a BlobService sync.

This however had some annoying consequences:

 - It became more and more complicated to track when we're in a context
   with an async runtime in the context or not, producing bugs like
   https://b.tvl.fyi/issues/304
 - The sync trait shielded away async clients from async worloads,
   requiring manual block_on code inside the gRPC client code, and
   spawn_blocking calls in consumers of the trait, even if they were
   async (like the gRPC server)
 - We had to write our own custom glue code (SyncReadIntoAsyncRead)
   to convert a sync io::Read into a tokio::io::AsyncRead, which already
   existed in tokio internally, but upstream ia hesitant to expose.

This now makes the BlobService trait async (via the async_trait macro,
like we already do in various gRPC parts), and replaces the sync readers
and writers with their async counterparts.

Tests interacting with a BlobService now need to have an async runtime
available, the easiest way for this is to mark the test functions
with the tokio::test macro, allowing us to directly .await in the test
function.

In places where we don't have an async runtime available from context
(like tvix-cli), we can pass one down explicitly.

Now that we don't provide a sync interface anymore, the (sync) FUSE
library now holds a pointer to a tokio runtime handle, and needs to at
least have 2 threads available when talking to a blob service (which is
why some of the tests now use the multi_thread flavor).

The FUSE tests got a bit more verbose, as we couldn't use the
setup_and_mount function accepting a callback anymore. We can hopefully
move some of the test fixture setup to rstest in the future to make this
less repetitive.

Co-Authored-By: Connor Brewster <cbrewster@hey.com>
Change-Id: Ia0501b606e32c852d0108de9c9016b21c94a3c05
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9329
Reviewed-by: Connor Brewster <cbrewster@hey.com>
Tested-by: BuildkiteCI
Reviewed-by: raitobezarius <tvl@lahfa.xyz>
This commit is contained in:
Florian Klink 2023-09-13 14:20:21 +02:00 • committed by flokli
parent 3de9601764
commit da6cbb4a45
25 changed files with 1700 additions and 1002 deletions
Download patch file Download diff file Expand all files Collapse all files

312
tvix/store/src/blobservice/tests.rs
View file

@ -1,6 +1,9 @@
use std::io;
use std::pin::pin;
use test_case::test_case;
use tokio::io::AsyncReadExt;
use tokio::io::AsyncSeekExt;
use super::B3Digest;
use super::BlobService;
@ -24,19 +27,25 @@ fn gen_sled_blob_service() -> impl BlobService {
#[test_case(gen_memory_blob_service(); "memory")]
#[test_case(gen_sled_blob_service(); "sled")]
fn has_nonexistent_false(blob_service: impl BlobService) {
assert!(!blob_service
.has(&fixtures::BLOB_A_DIGEST)
.expect("must not fail"));
tokio::runtime::Runtime::new().unwrap().block_on(async {
assert!(!blob_service
.has(&fixtures::BLOB_A_DIGEST)
.await
.expect("must not fail"));
})
}
/// Trying to read a non-existing blob should return a None instead of a reader.
#[test_case(gen_memory_blob_service(); "memory")]
#[test_case(gen_sled_blob_service(); "sled")]
fn not_found_read(blob_service: impl BlobService) {
assert!(blob_service
.open_read(&fixtures::BLOB_A_DIGEST)
.expect("must not fail")
.is_none())
tokio::runtime::Runtime::new().unwrap().block_on(async {
assert!(blob_service
.open_read(&fixtures::BLOB_A_DIGEST)
.await
.expect("must not fail")
.is_none())
})
}
/// Put a blob in the store, check has, get it back.
@ -46,165 +55,192 @@ fn not_found_read(blob_service: impl BlobService) {
#[test_case(gen_memory_blob_service(), &fixtures::BLOB_B, &fixtures::BLOB_B_DIGEST; "memory-big")]
#[test_case(gen_sled_blob_service(), &fixtures::BLOB_B, &fixtures::BLOB_B_DIGEST; "sled-big")]
fn put_has_get(blob_service: impl BlobService, blob_contents: &[u8], blob_digest: &B3Digest) {
let mut w = blob_service.open_write();
tokio::runtime::Runtime::new().unwrap().block_on(async {
let mut w = blob_service.open_write().await;
let l = io::copy(&mut io::Cursor::new(blob_contents), &mut w).expect("copy must succeed");
assert_eq!(
blob_contents.len(),
l as usize,
"written bytes must match blob length"
);
let l = tokio::io::copy(&mut io::Cursor::new(blob_contents), &mut w)
.await
.expect("copy must succeed");
assert_eq!(
blob_contents.len(),
l as usize,
"written bytes must match blob length"
);
let digest = w.close().expect("close must succeed");
let digest = w.close().await.expect("close must succeed");
assert_eq!(*blob_digest, digest, "returned digest must be correct");
assert_eq!(*blob_digest, digest, "returned digest must be correct");
assert!(
blob_service.has(blob_digest).expect("must not fail"),
"blob service should now have the blob"
);
assert!(
blob_service.has(blob_digest).await.expect("must not fail"),
"blob service should now have the blob"
);
let mut r = blob_service
.open_read(blob_digest)
.expect("open_read must succeed")
.expect("must be some");
let mut r = blob_service
.open_read(blob_digest)
.await
.expect("open_read must succeed")
.expect("must be some");
let mut buf: Vec<u8> = Vec::new();
let l = io::copy(&mut r, &mut buf).expect("copy must succeed");
let mut buf: Vec<u8> = Vec::new();
let mut pinned_reader = pin!(r);
let l = tokio::io::copy(&mut pinned_reader, &mut buf)
.await
.expect("copy must succeed");
// let l = io::copy(&mut r, &mut buf).expect("copy must succeed");
assert_eq!(
blob_contents.len(),
l as usize,
"read bytes must match blob length"
);
assert_eq!(
blob_contents.len(),
l as usize,
"read bytes must match blob length"
);
assert_eq!(blob_contents, buf, "read blob contents must match");
assert_eq!(blob_contents, buf, "read blob contents must match");
})
}
/// Put a blob in the store, and seek inside it a bit.
#[test_case(gen_memory_blob_service(); "memory")]
#[test_case(gen_sled_blob_service(); "sled")]
fn put_seek(blob_service: impl BlobService) {
let mut w = blob_service.open_write();
tokio::runtime::Runtime::new().unwrap().block_on(async {
let mut w = blob_service.open_write().await;
io::copy(&mut io::Cursor::new(&fixtures::BLOB_B.to_vec()), &mut w).expect("copy must succeed");
w.close().expect("close must succeed");
tokio::io::copy(&mut io::Cursor::new(&fixtures::BLOB_B.to_vec()), &mut w)
.await
.expect("copy must succeed");
w.close().await.expect("close must succeed");
// open a blob for reading
let mut r = blob_service
.open_read(&fixtures::BLOB_B_DIGEST)
.expect("open_read must succeed")
.expect("must be some");
// open a blob for reading
let mut r = blob_service
.open_read(&fixtures::BLOB_B_DIGEST)
.await
.expect("open_read must succeed")
.expect("must be some");
let mut pos: u64 = 0;
let mut pos: u64 = 0;
// read the first 10 bytes, they must match the data in the fixture.
{
let mut buf = [0; 10];
r.read_exact(&mut buf).expect("must succeed");
assert_eq!(
&fixtures::BLOB_B[pos as usize..pos as usize + buf.len()],
buf,
"expected first 10 bytes to match"
);
pos += buf.len() as u64;
}
// seek by 0 bytes, using SeekFrom::Start.
let p = r.seek(io::SeekFrom::Start(pos)).expect("must not fail");
assert_eq!(pos, p);
// read the next 10 bytes, they must match the data in the fixture.
{
let mut buf = [0; 10];
r.read_exact(&mut buf).expect("must succeed");
assert_eq!(
&fixtures::BLOB_B[pos as usize..pos as usize + buf.len()],
buf,
"expected data to match"
);
pos += buf.len() as u64;
}
// seek by 5 bytes, using SeekFrom::Start.
let p = r.seek(io::SeekFrom::Start(pos + 5)).expect("must not fail");
pos += 5;
assert_eq!(pos, p);
// read the next 10 bytes, they must match the data in the fixture.
{
let mut buf = [0; 10];
r.read_exact(&mut buf).expect("must succeed");
assert_eq!(
&fixtures::BLOB_B[pos as usize..pos as usize + buf.len()],
buf,
"expected data to match"
);
pos += buf.len() as u64;
}
// seek by 12345 bytes, using SeekFrom::
let p = r.seek(io::SeekFrom::Current(12345)).expect("must not fail");
pos += 12345;
assert_eq!(pos, p);
// read the next 10 bytes, they must match the data in the fixture.
{
let mut buf = [0; 10];
r.read_exact(&mut buf).expect("must succeed");
assert_eq!(
&fixtures::BLOB_B[pos as usize..pos as usize + buf.len()],
buf,
"expected data to match"
);
#[allow(unused_assignments)]
// read the first 10 bytes, they must match the data in the fixture.
{
let mut buf = [0; 10];
r.read_exact(&mut buf).await.expect("must succeed");
assert_eq!(
&fixtures::BLOB_B[pos as usize..pos as usize + buf.len()],
buf,
"expected first 10 bytes to match"
);
pos += buf.len() as u64;
}
}
// seek by 0 bytes, using SeekFrom::Start.
let p = r
.seek(io::SeekFrom::Start(pos))
.await
.expect("must not fail");
assert_eq!(pos, p);
// seeking to the end is okay…
let p = r
.seek(io::SeekFrom::Start(fixtures::BLOB_B.len() as u64))
.expect("must not fail");
pos = fixtures::BLOB_B.len() as u64;
assert_eq!(pos, p);
// read the next 10 bytes, they must match the data in the fixture.
{
let mut buf = [0; 10];
r.read_exact(&mut buf).await.expect("must succeed");
{
// but it returns no more data.
let mut buf: Vec<u8> = Vec::new();
r.read_to_end(&mut buf).expect("must not fail");
assert!(buf.is_empty(), "expected no more data to be read");
}
assert_eq!(
&fixtures::BLOB_B[pos as usize..pos as usize + buf.len()],
buf,
"expected data to match"
);
// seeking past the end…
match r.seek(io::SeekFrom::Start(fixtures::BLOB_B.len() as u64 + 1)) {
// should either be ok, but then return 0 bytes.
// this matches the behaviour or a Cursor<Vec<u8>>.
Ok(_pos) => {
pos += buf.len() as u64;
}
// seek by 5 bytes, using SeekFrom::Start.
let p = r
.seek(io::SeekFrom::Start(pos + 5))
.await
.expect("must not fail");
pos += 5;
assert_eq!(pos, p);
// read the next 10 bytes, they must match the data in the fixture.
{
let mut buf = [0; 10];
r.read_exact(&mut buf).await.expect("must succeed");
assert_eq!(
&fixtures::BLOB_B[pos as usize..pos as usize + buf.len()],
buf,
"expected data to match"
);
pos += buf.len() as u64;
}
// seek by 12345 bytes, using SeekFrom::
let p = r
.seek(io::SeekFrom::Current(12345))
.await
.expect("must not fail");
pos += 12345;
assert_eq!(pos, p);
// read the next 10 bytes, they must match the data in the fixture.
{
let mut buf = [0; 10];
r.read_exact(&mut buf).await.expect("must succeed");
assert_eq!(
&fixtures::BLOB_B[pos as usize..pos as usize + buf.len()],
buf,
"expected data to match"
);
#[allow(unused_assignments)]
{
pos += buf.len() as u64;
}
}
// seeking to the end is okay…
let p = r
.seek(io::SeekFrom::Start(fixtures::BLOB_B.len() as u64))
.await
.expect("must not fail");
pos = fixtures::BLOB_B.len() as u64;
assert_eq!(pos, p);
{
// but it returns no more data.
let mut buf: Vec<u8> = Vec::new();
r.read_to_end(&mut buf).expect("must not fail");
r.read_to_end(&mut buf).await.expect("must not fail");
assert!(buf.is_empty(), "expected no more data to be read");
}
// or not be okay.
Err(_) => {}
}
// TODO: this is only broken for the gRPC version
// We expect seeking backwards or relative to the end to fail.
// r.seek(io::SeekFrom::Current(-1))
// .expect_err("SeekFrom::Current(-1) expected to fail");
// seeking past the end…
match r
.seek(io::SeekFrom::Start(fixtures::BLOB_B.len() as u64 + 1))
.await
{
// should either be ok, but then return 0 bytes.
// this matches the behaviour or a Cursor<Vec<u8>>.
Ok(_pos) => {
let mut buf: Vec<u8> = Vec::new();
r.read_to_end(&mut buf).await.expect("must not fail");
assert!(buf.is_empty(), "expected no more data to be read");
}
// or not be okay.
Err(_) => {}
}
// r.seek(io::SeekFrom::Start(pos - 1))
// .expect_err("SeekFrom::Start(pos-1) expected to fail");
// TODO: this is only broken for the gRPC version
// We expect seeking backwards or relative to the end to fail.
// r.seek(io::SeekFrom::Current(-1))
// .expect_err("SeekFrom::Current(-1) expected to fail");
// r.seek(io::SeekFrom::End(0))
// .expect_err("SeekFrom::End(_) expected to fail");
// r.seek(io::SeekFrom::Start(pos - 1))
// .expect_err("SeekFrom::Start(pos-1) expected to fail");
// r.seek(io::SeekFrom::End(0))
// .expect_err("SeekFrom::End(_) expected to fail");
})
}