History

Florian Klink 1c15154b83 feat(tvix/store): make blobstore stream chunks This changes the RPC methods to return/consume a stream of chunks, instead of a very big message containing the whole blob, to keep message sizes in manageable sizes (less than 4MiB). Change-Id: I2a3a50f07b059d8a2f5196860254adff98c8a352 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7651 Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI		2022-12-28 13:55:18 +00:00
..
docs	docs(tvix/store): add README, document services and store model	2022-12-26 11:38:52 +00:00
protos	feat(tvix/store): make blobstore stream chunks	2022-12-28 13:55:18 +00:00
src	feat(tvix/store): implement Directory::validate()	2022-12-28 10:58:50 +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): implement Directory::validate()	2022-12-28 10:58:50 +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.