refactor(tvix): move castore into tvix-castore crate r/6629

This splits the pure content-addressed layers from tvix-store into a
`castore` crate, and only leaves PathInfo related things, as well as the
CLI entrypoint in the tvix-store crate.

Notable changes:
 - `fixtures` and `utils` had to be moved out of the `test` cfg, so they
   can be imported from tvix-store.
 - Some ad-hoc fixtures in the test were moved to proper fixtures in the
   same step.
 - The protos are now created by a (more static) recipe in the protos/
   directory.

The (now two) golang targets are commented out, as it's not possible to
update them properly in the same CL. This will be done by a followup CL
once this is merged (and whitby deployed)

Bug: https://b.tvl.fyi/issues/301

Change-Id: I8d675d4bf1fb697eb7d479747c1b1e3635718107
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9370
Reviewed-by: tazjin <tazjin@tvl.su>
Reviewed-by: flokli <flokli@flokli.de>
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: Connor Brewster <cbrewster@hey.com>

1 files changed, 246 insertions, 0 deletions

diff --git a/tvix/castore/src/blobservice/tests.rs b/tvix/castore/src/blobservice/tests.rs
new file mode 100644
index 000000000000..fe390b537eb8
--- /dev/null
+++ b/tvix/castore/src/blobservice/tests.rs
@@ -0,0 +1,246 @@
+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;
+use super::MemoryBlobService;
+use super::SledBlobService;
+use crate::fixtures;
+
+// TODO: avoid having to define all different services we test against for all functions.
+// maybe something like rstest can be used?
+
+fn gen_memory_blob_service() -> impl BlobService {
+    MemoryBlobService::default()
+}
+fn gen_sled_blob_service() -> impl BlobService {
+    SledBlobService::new_temporary().unwrap()
+}
+
+// TODO: add GRPC blob service here.
+
+/// Using [BlobService::has] on a non-existing blob should return false
+#[test_case(gen_memory_blob_service(); "memory")]
+#[test_case(gen_sled_blob_service(); "sled")]
+fn has_nonexistent_false(blob_service: impl BlobService) {
+    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) {
+    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.
+/// We test both with small and big blobs.
+#[test_case(gen_memory_blob_service(), &fixtures::BLOB_A, &fixtures::BLOB_A_DIGEST; "memory-small")]
+#[test_case(gen_sled_blob_service(), &fixtures::BLOB_A, &fixtures::BLOB_A_DIGEST; "sled-small")]
+#[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) {
+    tokio::runtime::Runtime::new().unwrap().block_on(async {
+        let mut w = blob_service.open_write().await;
+
+        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().await.expect("close must succeed");
+
+        assert_eq!(*blob_digest, digest, "returned digest must be correct");
+
+        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)
+            .await
+            .expect("open_read must succeed")
+            .expect("must be some");
+
+        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, 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) {
+    tokio::runtime::Runtime::new().unwrap().block_on(async {
+        let mut w = blob_service.open_write().await;
+
+        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)
+            .await
+            .expect("open_read must succeed")
+            .expect("must be some");
+
+        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).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);
+
+        // 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 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).await.expect("must not fail");
+            assert!(buf.is_empty(), "expected no more data to be read");
+        }
+
+        // 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(_) => {}
+        }
+
+        // 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::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");
+    })
+}