History

Florian Klink 2798803f76 refactor(tvix/castore): introduce "cloud" feature flag This controls whether tvix-castore has support for various cloud backends or not. Use this to control the set of feature flags for the object_store backend, and only enable the aws, azure and gcp ones if it's set. In the future this can be used to enable/disable other cloud backends too. Without feature flags, `object_store` already supports the `InMemory` and `LocalFilesystem` backends, and we also want to unconditionally enable the `http` one. Make sure at least the construction of these services is covered in the tests. Similarly, the tvix-store crate, which provides the tvix-store CLI has a `cloud` feature flag too (defaulting to enabled). Change-Id: I9fb9c87b740e7dc83f8ff7a0862905d036d513f2 Reviewed-on: https://cl.tvl.fyi/c/depot/+/11204 Autosubmit: flokli <flokli@flokli.de> Reviewed-by: raitobezarius <tvl@lahfa.xyz> Tested-by: BuildkiteCI		2024-03-20 12:17:42 +00:00
..
docs	chore(tvix/castore): move data model docs to here	2023-11-02 09:08:20 +00:00
protos	refactor(tvix/*/protos): separate lint target	2023-12-11 22:35:39 +00:00
src	refactor(tvix/store/pathinfo/from_addr): use match guards	2024-03-20 11:53:41 +00:00
build.rs	fix(tvix): don't emit rerun-if-changed	2024-03-16 09:34:10 +00:00
Cargo.toml	refactor(tvix/castore): introduce "cloud" feature flag	2024-03-20 12:17:42 +00:00
default.nix	feat(tvix/store): use reqwests' rustls-native-roots feature	2024-03-03 15:32:38 +00:00
README.md	fix(tvix/store): rename Read method in Readme	2023-09-26 15:24:32 +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 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.