tvl-depot/tvix/store
sinavir 0f92400112 fix(tvix/nar-bridge): Remove name check for root node in nar generation
Nar-bridge tried to parse the name of the protobuf node encoded in the
URL into a PathComponent but this name was empty, leading to an error
when the user tried to retrieve the nar file.

This was an oversight from the conversion to stricter types (some of the
CLs in the serious containing cl/12217).

We need a version converting a protobuf without a name to our stricter
types, but an empty PathComponent cannot be constructed.

So we need a into_name_and_node() version that returns the name as
Bytes, not PathComponent.

Change-Id: I2996cdd2e0107133e502748947298f512f1cc521
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12504
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
2024-09-24 09:45:33 +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/nar-bridge): Remove name check for root node in nar generation 2024-09-24 09:45:33 +00:00
build.rs feat(tvix): drop usage of sparseTree in favor of lib.sourceByRegex 2024-08-19 16:56:19 +00:00
Cargo.toml chore(tvix): Migrate members to inherit deps from workspace 2024-08-29 14:37:22 +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

//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.