History

Florian Klink 0bf2b0ef11 feat(tvix/store): implement reflection This implements grpc.reflection.v1alpha.ServerReflection, and will make tools like evans automatically discover available services, without having to specify the path to the .proto files client-side. It's behind a reflection feature flag, which is enabled by default. Change-Id: Icbcb5eb05ceede5b9952e38a2ba72eaa6fa8a437 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7435 Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI		2022-12-30 20:25:09 +00:00
..
docs	docs(tvix/store): add README, document services and store model	2022-12-26 11:38:52 +00:00
protos	chore(tvix/store/protos): more idiomatic go	2022-12-30 15:18:02 +00:00
src	feat(tvix/store): implement reflection	2022-12-30 20:25:09 +00:00
build.rs	feat(tvix/store): implement reflection	2022-12-30 20:25:09 +00:00
Cargo.toml	feat(tvix/store): implement reflection	2022-12-30 20:25:09 +00:00
default.nix	feat(tvix/store): implement reflection	2022-12-30 20:25:09 +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.