History

Brian Olsen 39ef171e00 chore(tvix): Retain original passthru in Rust builds When using the runTests feature of crate2nix the derivation that runs the tests is put into passthru.test but all default.nix files for Rust crates in Tvix threw that away. This commit retains passthru so that you can get access to the test derivation. Change-Id: I8b7b7db57a49069348f08c12c00a3b1a41a0c05b Reviewed-on: https://cl.tvl.fyi/c/depot/+/12215 Reviewed-by: flokli <flokli@flokli.de> Tested-by: BuildkiteCI		2024-08-15 23:37:00 +00:00
..
protos	refactor(tvix/*/protos): separate lint target	2023-12-11 22:35:39 +00:00
src	refactor(tvix/castore): move *Node and Directory to crate root	2024-08-13 18:39:49 +00:00
build.rs	fix(tvix/{store,castore,build}): Compile tonic w/o config in build.rs	2024-07-09 13:24:22 +00:00
Cargo.toml	feat(tvix): Jemalloc -> MiMalloc	2024-08-08 08:06:23 +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.