History

Florian Klink bd6894d265 fix(tvix/store/pathinfo): use gRPC NarCalculationService If the PathInfoService is using gRPC, expose it via the nar_calculation_service() method in the PathInfoService. Also pass nar_calculation_service through in tha blanket impl. This now causes a `tvix-store import` using the default config to not fall back to `SimpleRenderer`, which will calculate the NAR hash and size by downloading the uploaded blobs (and blobs it didn't need to upload) locally, making such imports faster. Change-Id: If2c3fe6584e9093cba322d2360f355a3923904ae Reviewed-on: https://cl.tvl.fyi/c/depot/+/12658 Tested-by: BuildkiteCI Reviewed-by: edef <edef@edef.eu> Autosubmit: flokli <flokli@flokli.de>		2024-10-18 21:45:55 +00:00
..
protos	feat(tvix): drop usage of sparseTree in favor of lib.sourceByRegex	2024-08-19 16:56:19 +00:00
src	fix(tvix/store/pathinfo): use gRPC NarCalculationService	2024-10-18 21:45:55 +00:00
build.rs	chore(tvix): bump crate dependencies	2024-10-12 12:13:55 +00:00
Cargo.toml	refactor(tvix/store): remove use of lazy_static	2024-10-17 22:15:48 +00:00
default.nix	chore(tvix): Retain original passthru in Rust builds	2024-08-15 23:37:00 +00:00
README.md	fix(tvix/store): rename Read method in Readme	2023-09-26 15:24:32 +00:00

README.md

//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

The store consists out of two different gRPC services, tvix.castore.v1 for the low-level content-addressed bits, and tvix.store.v1 for the Nix and StorePath-specific bits.

Check the protos/ subfolder both here and in castore 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


localhost:8000> package tvix.castore.v1
tvix.castore.v1@localhost:8000> service BlobService

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

tvix.castore.v1.BlobService@localhost:8000> call Read --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.