be48ba75ab
NixHTTPPathInfoService acts as a bridge in between the Nix HTTP Binary cache protocol provided by Nix binary caches such as cache.nixos.org, and the Tvix Store Model. It implements the [PathInfoService] trait in an interesting way: Every [PathInfoService::get] fetches the .narinfo and referred NAR file, inserting components into a [BlobService] and [DirectoryService], then returning a [PathInfo] struct with the root. Due to this being quite a costly operation, clients are expected to layer this service with store composition, so they're only ingested once. The client is expected to be (indirectly) using the same [BlobService] and [DirectoryService], so able to fetch referred Directories and Blobs. [PathInfoService::put] and [PathInfoService::nar] are not implemented and return an error if called. This behaves very similar to the nar-bridge-pathinfo code in nar-bridge, except it's now in Rust. Change-Id: Ia03d4fed9d0657965d100299af97cd917a03f2f0 Reviewed-on: https://cl.tvl.fyi/c/depot/+/10069 Tested-by: BuildkiteCI Autosubmit: flokli <flokli@flokli.de> Reviewed-by: raitobezarius <tvl@lahfa.xyz> |
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| docs | ||
| protos | ||
| src | ||
| build.rs | ||
| Cargo.toml | ||
| default.nix | ||
| 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.