tvl-depot/tvix/store
Florian Klink 638f3e874d feat(tvix/store/fuse): implement open explicitly
This "reverts" commit 9f600de226 (the
initial revert of f5e291cf83).

Now with BlobService returning a BlobReader that implements io::Seek, we
can actually just call blob_reader.seek(io::SeekFrom::Start(offset as
u64)).

This means, we currently will fail to seek backwards inside a file.

Change-Id: I9c19448df6831a3537252f99210374f2126ecfc0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8886
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: raitobezarius <tvl@lahfa.xyz>
2023-07-21 18:52:47 +00:00
..
docs docs(tvix/store): various improvements 2023-07-07 09:48:32 +00:00
protos chore(3p/sources): Bump channels & overlays 2023-07-08 10:46:31 +00:00
src feat(tvix/store/fuse): implement open explicitly 2023-07-21 18:52:47 +00:00
build.rs refactor(tvix/store): remove needless borrow in build.rs 2023-02-15 18:40:36 +00:00
Cargo.toml feat(tvix/store/blobsvc): add from_addr 2023-06-14 20:44:36 +00:00
default.nix chore(tvix/store): drop separate bin package 2023-03-14 22:23:10 +00:00
README.md docs(tvix/store): drop nar-bridge references 2023-06-09 15:33:14 +00:00

//tvix/store

This contains the code hosting the tvix-store.

For the local store, Nix realizes files on the filesystem in /nix/store (and maintains some metadata in a SQLite database). For "remote stores", it communicates this metadata in NAR (Nix ARchive) and NARInfo format.

Compared to the Nix model, tvix-store stores data on a much more granular level than that, which provides more deduplication possibilities, and more granular copying.

However, enough information is preserved to still be able to render NAR and NARInfo when needed.

More Information

Check the protos/ subfolder for the definition of the exact RPC methods and messages.

Interacting with the GRPC service manually

The shell environment in //tvix provides evans, which is an interactive REPL-based gPRC client.

You can use it to connect to a tvix-store and call the various RPC methods.

$ cargo run -- daemon &
$ evans --host localhost --port 8000 -r repl
  ______
 |  ____|
 | |__    __   __   __ _   _ __    ___
 |  __|   \ \ / /  / _. | | '_ \  / __|
 | |____   \ V /  | (_| | | | | | \__ \
 |______|   \_/    \__,_| |_| |_| |___/

 more expressive universal gRPC client


tvix.store.v1@localhost:8000> service BlobService

tvix.store.v1.BlobService@localhost:8000> call Put --bytes-from-file
data (TYPE_BYTES) => /run/current-system/system
{
  "digest": "KOM3/IHEx7YfInAnlJpAElYezq0Sxn9fRz7xuClwNfA="
}

tvix.store.v1.BlobService@localhost:8000> call Get --bytes-as-base64
digest (TYPE_BYTES) => KOM3/IHEx7YfInAnlJpAElYezq0Sxn9fRz7xuClwNfA=
{
  "data": "eDg2XzY0LWxpbnV4"
}

$ echo eDg2XzY0LWxpbnV4 | base64 -d
x86_64-linux

Thanks to tvix-store providing gRPC Server Reflection (with reflection feature), you don't need to point evans to the .proto files.