path: root/tvix/store/protos/pathinfo.proto

// SPDX-License-Identifier: MIT
// Copyright © 2022 The Tvix Authors
syntax = "proto3";

package tvix.store.v1;

import "tvix/castore/protos/castore.proto";

option go_package = "code.tvl.fyi/tvix/store-go;storev1";

// PathInfo shows information about a Nix Store Path.
// That's a single element inside /nix/store.
message PathInfo {
    // The path can be a directory, file or symlink.
    tvix.castore.v1.Node node = 1;

    // List of references (output path hashes)
    // This really is the raw *bytes*, after decoding nixbase32, and not a
    // base32-encoded string.
    repeated bytes references = 2;

    // see below.
    NARInfo narinfo = 3;
}

// Represents a path in the Nix store (a direct child of STORE_DIR).
// It is commonly formatted by a nixbase32-encoding the digest, and
// concatenating the name, separated by a `-`.
message StorePath {
    // The string after digest and `-`.
    string name = 1;

    // The digest (20 bytes).
    bytes digest = 2;
}

// Nix C++ uses NAR (Nix Archive) as a format to transfer store paths,
// and stores metadata and signatures in NARInfo files.
// Store all these attributes in a separate message.
//
// This is useful to render .narinfo files to clients, or to preserve/validate
// these signatures.
// As verifying these signatures requires the whole NAR file to be synthesized,
// moving to another signature scheme is desired.
// Even then, it still makes sense to hold this data, for old clients.
message NARInfo {
    // This represents a (parsed) signature line in a .narinfo file.
    message Signature {
        string name = 1;
        bytes data = 2;
    };

    // This size of the NAR file, in bytes.
    uint64 nar_size = 1;

    // The sha256 of the NAR file representation.
    bytes nar_sha256 = 2;

    // The signatures in a .narinfo file.
    repeated Signature signatures = 3;

    // A list of references. To validate .narinfo signatures, a fingerprint
    // needs to be constructed.
    // This fingerprint doesn't just contain the hashes of the output paths of
    // all references (like PathInfo.references), but their whole (base)names,
    // so we need to keep them somewhere.
    repeated string reference_names = 4;

    // The StorePath of the .drv file producing this output.
    // The .drv suffix is omitted in its `name` field.
    StorePath deriver = 5;
}