History

Florian Klink e05e8bdd03 docs(tvix/store): add README, document services and store model These are intended to help digest the protocol definitions for tvix- store, and how they tie into the whole concept. Co-Authored-By: Vincent Ambo <mail@tazj.in> Change-Id: Ic1ba3ba41ef599209453f15d0ac2e07a6144bcca Reviewed-on: https://cl.tvl.fyi/c/depot/+/7439 Tested-by: BuildkiteCI Reviewed-by: tazjin <tazjin@tvl.su>		2022-12-26 11:38:52 +00:00
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docs	docs(tvix/store): add README, document services and store model	2022-12-26 11:38:52 +00:00
protos	docs(tvix/store): add README, document services and store model	2022-12-26 11:38:52 +00:00
src	feat(tvix/store): use tonic-build for protos	2022-12-26 11:38:52 +00:00
build.rs	feat(tvix/store): use tonic-build for protos	2022-12-26 11:38:52 +00:00
Cargo.toml	feat(tvix/store): use tonic-build for protos	2022-12-26 11:38:52 +00:00
default.nix	feat(tvix/proto): add rpc_directory.proto	2022-12-22 14:35:32 +00:00
README.md	docs(tvix/store): add README, document services and store model	2022-12-26 11:38:52 +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 (handled by //tvix/nar-bridge).

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 &
$ 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.