refactor(snix/castore-http/cli): ask for root directory digest

Restrict the CLI to only root directories, passing the blake3 digest of
the root directory.

Usually we want to serve a directory, and we now have a `snix-castore
ingest` sucommand, and copying the output from that command is much less
effort than constructing a proto message.

More advanced usecases can still use the get_root_node_contents library
function and pass in other nodes.

Change-Id: I66c2c0a15723b43b5b0cffc1c201391df57dd602
Reviewed-on: https://cl.snix.dev/c/snix/+/30321
Reviewed-by: Stefan Junker <mail@stefanjunker.de>
Tested-by: besadii

snix/Cargo.lock

@@ -4258,13 +4258,10 @@ dependencies = [
  "axum-range",
  "axum-test",
  "blake3",
- "bytes",
  "clap",
- "data-encoding",
  "mime",
  "mime_guess",
  "path-clean",
- "prost",
  "snix-castore",
  "tokio",
  "tokio-listener",

snix/Cargo.nix

@@ -13966,19 +13966,11 @@ rec {
             name = "axum-range";
             packageId = "axum-range";
           }
-          {
-            name = "bytes";
-            packageId = "bytes";
-          }
           {
             name = "clap";
             packageId = "clap";
             features = [ "derive" ];
           }
-          {
-            name = "data-encoding";
-            packageId = "data-encoding";
-          }
           {
             name = "mime";
             packageId = "mime";
@@ -13991,10 +13983,6 @@ rec {
             name = "path-clean";
             packageId = "path-clean";
           }
-          {
-            name = "prost";
-            packageId = "prost";
-          }
           {
             name = "snix-castore";
             packageId = "snix-castore";

snix/castore-http/Cargo.toml

@@ -8,13 +8,10 @@ anyhow.workspace = true
 axum = { workspace = true, features = ["tracing"] }
 axum-extra.workspace = true
 axum-range.workspace = true
-bytes.workspace = true
 clap = { workspace = true, features = ["derive"] }
-data-encoding.workspace = true
 mime_guess = "2.0.5"
 mime = "0.3.17"
 path-clean.workspace = true
-prost.workspace = true
 tokio = { workspace = true, features = [ "tracing"] }
 tokio-listener = { workspace = true, features = ["axum07", "clap", "multi-listener", "sd_listen"] }
 tracing.workspace = true

snix/castore-http/src/cli.rs

@@ -1,5 +1,5 @@
 use clap::Parser;
-use snix_castore::utils::ServiceUrlsGrpc;
+use snix_castore::{utils::ServiceUrlsGrpc, B3Digest};
 
 #[derive(Parser)]
 #[command(author, version, about)]
@@ -10,13 +10,9 @@ pub struct CliArgs {
     // The castore services addresses
     #[clap(flatten)]
     pub service_addrs: ServiceUrlsGrpc,
-    /// The castore root node to serve, URL-safe base64-encoded
-    #[arg(
-        short,
-        long,
-        help = "The castore root node to serve, URL-safe base64-encoded"
-    )]
-    pub root_node: String,
+    /// The root directory digest to serve.
+    #[arg(short, long, help = "The root directory digest to serve")]
+    pub root_directory: B3Digest,
     /// The name of the file to serve if a client requests a directory e.g. index.html index.htm
     #[arg(
         short,

snix/castore-http/src/main.rs

@@ -1,47 +1,23 @@
-use snix_castore_http::cli::CliArgs;
-
-use anyhow::{bail, Context};
-use bytes::Bytes;
 use clap::Parser;
-use data_encoding::BASE64URL_NOPAD;
-use prost::Message;
+use snix_castore::Node;
+use snix_castore_http::cli::CliArgs;
 
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
     tracing_subscriber::fmt().init();
 
-    let CliArgs {
-        listen_args,
-        service_addrs,
-        root_node,
-        index_names,
-        auto_index,
-    }: CliArgs = snix_castore_http::cli::CliArgs::parse();
-
-    // b64decode the root node passed *by the user*
-    let root_entry_proto = BASE64URL_NOPAD
-        .decode(root_node.as_bytes())
-        .context("unable to decode root node b64")?;
-
-    // check the proto size to be somewhat reasonable before parsing it.
-    if root_entry_proto.len() > 4096 {
-        bail!("rejected, too large root node");
-    }
-
-    // parse the proto
-    let root_entry: snix_castore::proto::Entry = Message::decode(Bytes::from(root_entry_proto))
-        .context("unable to decode root node proto")?;
-
-    let root_node = root_entry
-        .try_into_anonymous_node()
-        .context("root node validation failed")?;
+    let args: CliArgs = snix_castore_http::cli::CliArgs::parse();
 
     snix_castore_http::router::gen_router(
-        listen_args,
-        service_addrs,
-        root_node,
-        &index_names,
-        auto_index,
+        args.listen_args,
+        args.service_addrs,
+        Node::Directory {
+            digest: args.root_directory,
+            // size doesn't really matter here, we're not doing inode allocation.
+            size: 0,
+        },
+        &args.index_names,
+        args.auto_index,
     )
     .await
 }