feat(peer): prototype streamed installs

Add a streamed-install prototype that can receive archive-derived install bytes
straight into local/ without first storing the peer-owned root archive payload.
This is intended for low-disk clients that want to install a game but opt out of
becoming a downloadable peer source for that game.

The protocol gains a current-version-only StreamInstall request and framed
StreamInstallFrame responses. The peer core owns the generic transport,
transaction, path validation, size checks, CRC32 verification, and lifecycle
state. The archive-specific work is hidden behind StreamInstallProvider so the
prototype can use unrar while the final implementation can swap in a better
provider without rewriting the peer command path.

The receiver writes into .local.installing and only promotes to local/ after the
full stream verifies. It deliberately does not write the root version.ini or
archive files, so the settled local state is installed=true, downloaded=false,
and availability=LocalOnly. That preserves the existing rule that local/ is not
served to peers and makes streamed receivers non-sources by construction.

The CLI is the only caller for now. It exposes stream-install and provides the
prototype unrar implementation with unrar lt for entry metadata and unrar p for
file bytes. This is simple and good enough to prove non-solid archive streaming,
but it is not the production provider shape for solid archives because per-file
unrar p would repeatedly decompress prefixes. The Tauri app explicitly passes
stream_install_provider: None, so the GUI behavior stays unchanged until a real
product path is designed.

Document the production-readiness work in NEXT_STEPS.md. The main follow-up is
to make the provider abstraction final-ish and replace the per-file CLI unrar
provider with a one-pass archive provider, then wire a deliberate GUI low-disk
mode, retry semantics, and broader failure scenarios.

Test Plan:
- just fmt
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= just test
- python3 crates/lanspread-peer-cli/scripts/run_extended_scenarios.py \
  S39 S40 --build-image
- RUSTC_WRAPPER= CARGO_BUILD_RUSTC_WRAPPER= just clippy
- git diff --check
- git diff --cached --check

Follow-up: NEXT_STEPS.md
This commit is contained in:
2026-06-07 20:31:51 +02:00
parent 8a8437036d
commit 373def6d44
22 changed files with 1465 additions and 14 deletions
+233
View File
@@ -11,6 +11,7 @@ use std::{
use lanspread_db::db::{GameDB, GameFileDescription};
use tokio::sync::{RwLock, mpsc::UnboundedSender};
use tokio_util::sync::CancellationToken;
use crate::{
InstallOperation,
@@ -33,6 +34,7 @@ use crate::{
peer_db::PeerGameDB,
remote_peer::ensure_peer_id_for_addr,
services::{HandshakeCtx, perform_handshake_with_peer},
stream_install::receive_streamed_install,
};
// =============================================================================
@@ -450,6 +452,91 @@ pub async fn handle_install_game_command(
spawn_install_operation(ctx, tx_notify_ui, id);
}
pub async fn handle_stream_install_game_command(
ctx: &Ctx,
tx_notify_ui: &UnboundedSender<PeerEvent>,
id: String,
) {
if !catalog_contains(ctx, &id).await {
log::warn!("Ignoring streamed install command for non-catalog game {id}");
send_download_failed(tx_notify_ui, &id);
return;
}
let games_folder = { ctx.game_dir.read().await.clone() };
let game_root = games_folder.join(&id);
if local_dir_is_directory(&game_root).await {
log::warn!("Ignoring streamed install command for already-installed game {id}");
send_download_failed(tx_notify_ui, &id);
return;
}
let expected_version = catalog_expected_version(ctx, &id).await;
let mut peers = {
match ctx
.peer_game_db
.read()
.await
.validate_file_sizes_majority(&id, expected_version.as_deref())
{
Ok((validated_files, peer_whitelist, _)) if !validated_files.is_empty() => {
peer_whitelist
}
Ok(_) => {
log::error!("No trusted peers available for streamed install of {id}");
send_download_failed(tx_notify_ui, &id);
return;
}
Err(err) => {
log::error!(
"File size majority validation failed for streamed install {id}: {err}"
);
send_download_failed(tx_notify_ui, &id);
return;
}
}
};
peers.sort();
let Some(peer_addr) = peers.into_iter().next() else {
log::error!("No peer selected for streamed install of {id}");
send_download_failed(tx_notify_ui, &id);
return;
};
match begin_operation(ctx, tx_notify_ui, &id, OperationKind::Downloading).await {
BeginOperationResult::Started => {}
BeginOperationResult::AlreadyActive => {
log::warn!("Operation for {id} already in progress; ignoring streamed install request");
return;
}
BeginOperationResult::DrainTimedOut => {
log::error!("Timed out waiting for outbound transfers before streamed install of {id}");
send_download_failed(tx_notify_ui, &id);
return;
}
}
let cancel_token = ctx.shutdown.child_token();
ctx.active_downloads
.write()
.await
.insert(id.clone(), cancel_token.clone());
let ctx_clone = ctx.clone();
let tx_notify_ui = tx_notify_ui.clone();
ctx.task_tracker.spawn(async move {
run_stream_install_operation(
ctx_clone,
tx_notify_ui,
id,
game_root,
peer_addr,
cancel_token,
)
.await;
});
}
/// Handles the `UninstallGame` command.
pub async fn handle_uninstall_game_command(
ctx: &Ctx,
@@ -490,6 +577,151 @@ pub async fn handle_cancel_download_command(
cancel_token.cancel();
}
async fn run_stream_install_operation(
ctx: Ctx,
tx_notify_ui: UnboundedSender<PeerEvent>,
id: String,
game_root: PathBuf,
peer_addr: SocketAddr,
cancel_token: CancellationToken,
) {
let download_guard = OperationGuard::download(
id.clone(),
ctx.active_operations.clone(),
ctx.active_downloads.clone(),
tx_notify_ui.clone(),
);
events::send(
&tx_notify_ui,
PeerEvent::DownloadGameFilesBegin { id: id.clone() },
);
let transaction = match install::begin_streamed_install(&game_root, ctx.state_dir.as_ref(), &id)
.await
{
Ok(transaction) => transaction,
Err(err) => {
log::error!("Failed to prepare streamed install for {id}: {err}");
finish_failed_stream_download(&ctx, &tx_notify_ui, &id, download_guard, false).await;
return;
}
};
let receive_result = receive_streamed_install(
peer_addr,
&id,
transaction.staging_dir(),
tx_notify_ui.clone(),
cancel_token.clone(),
)
.await;
match receive_result {
Ok(()) => {
if transition_download_to_install(&ctx, &tx_notify_ui, &id, OperationKind::Installing)
.await
{
clear_active_download(&ctx, &id).await;
send_download_finished(&tx_notify_ui, &id);
download_guard.disarm();
commit_streamed_install(&ctx, &tx_notify_ui, id, transaction).await;
} else {
if let Err(err) = transaction.rollback().await {
log::error!("Failed to roll back streamed install for {id}: {err}");
}
finish_failed_stream_download(&ctx, &tx_notify_ui, &id, download_guard, false)
.await;
}
}
Err(err) => {
if let Err(rollback_err) = transaction.rollback().await {
log::error!("Failed to roll back streamed install for {id}: {rollback_err}");
}
let download_was_cancelled = cancel_token.is_cancelled();
if download_was_cancelled {
log::info!("Streamed install download cancelled for {id}: {err}");
} else {
log::error!("Streamed install download failed for {id}: {err}");
}
finish_failed_stream_download(
&ctx,
&tx_notify_ui,
&id,
download_guard,
download_was_cancelled,
)
.await;
}
}
}
async fn finish_failed_stream_download(
ctx: &Ctx,
tx_notify_ui: &UnboundedSender<PeerEvent>,
id: &str,
guard: OperationGuard,
cancelled: bool,
) {
if let Err(err) = refresh_local_game_for_ending_operation(ctx, tx_notify_ui, id).await {
log::error!("Failed to refresh local library after streamed install failure: {err}");
}
end_download_operation(ctx, tx_notify_ui, id).await;
guard.disarm();
send_download_failed_unless_cancelled(tx_notify_ui, id, cancelled);
}
async fn commit_streamed_install(
ctx: &Ctx,
tx_notify_ui: &UnboundedSender<PeerEvent>,
id: String,
transaction: install::StreamedInstallTransaction,
) {
let operation_guard = OperationGuard::new(
id.clone(),
ctx.active_operations.clone(),
tx_notify_ui.clone(),
);
events::send(
tx_notify_ui,
PeerEvent::InstallGameBegin {
id: id.clone(),
operation: InstallOperation::Installing,
},
);
match transaction.commit().await {
Ok(()) => {
if let Err(err) = refresh_local_game_for_ending_operation(ctx, tx_notify_ui, &id).await
{
log::error!("Failed to refresh local library after streamed install: {err}");
}
end_operation(ctx, tx_notify_ui, &id).await;
operation_guard.disarm();
events::send(
tx_notify_ui,
PeerEvent::InstallGameFinished { id: id.clone() },
);
}
Err(err) => {
log::error!("Streamed install commit failed for {id}: {err}");
if let Err(refresh_err) =
refresh_local_game_for_ending_operation(ctx, tx_notify_ui, &id).await
{
log::error!(
"Failed to refresh local library after streamed install commit failure: {refresh_err}"
);
}
end_operation(ctx, tx_notify_ui, &id).await;
operation_guard.disarm();
events::send(
tx_notify_ui,
PeerEvent::InstallGameFailed { id: id.clone() },
);
}
}
}
fn spawn_install_operation(ctx: &Ctx, tx_notify_ui: &UnboundedSender<PeerEvent>, id: String) {
let ctx = ctx.clone();
let tx_notify_ui = tx_notify_ui.clone();
@@ -1264,6 +1496,7 @@ mod tests {
TaskTracker::new(),
Arc::new(RwLock::new(GameCatalog::from_ids(["game".to_string()]))),
Arc::new(RwLock::new(HashMap::new())),
Arc::new(crate::NoopStreamInstallProvider),
)
}