1 files changed, 33 insertions, 1 deletions

diff --git a/src/main.rs b/src/main.rs
index 09b365b..4cfae66 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -86,7 +86,30 @@ async fn main() -> Result<()> {
         "Using Mycelium REST API"
     );
 
-    let seeds: Vec<String> = args.seeds.clone();
+    let mut seeds: Vec<String> = args.seeds.clone();
+    let (state_file, remembered) = match &args.state_file {
+        Some(path) => {
+            let (file, remembered) = swarm::state_file::StateFile::open(path.clone());
+            (Some(Arc::new(file)), remembered)
+        }
+        None => (None, None),
+    };
+    if let Some(remembered) = &remembered {
+        info!(
+            swarm_id = %remembered.swarm_id,
+            seeds = remembered.seeds.len(),
+            "Remembering a swarm from the state file"
+        );
+        for seed in &remembered.seeds {
+            if !seeds.contains(seed) {
+                seeds.push(seed.clone());
+            }
+        }
+    } else if args.genesis && state_file.is_none() {
+        warn!(
+            "--genesis without --state-file: every restart with --genesis starts another new swarm"
+        );
+    }
     debug!(seed_count = seeds.len(), "Loaded bootstrap configuration");
 
     let (sync_tx, sync_rx) = mpsc::unbounded_channel();
@@ -141,6 +164,7 @@ async fn main() -> Result<()> {
         electorate_window: Duration::from_secs(args.electorate_window_days * 24 * 3600),
         blobs: Arc::new(swarm::blob::Blobs::new(args.blob_chunk_kib * 1024)),
         protocol_writers: Arc::new(args.protocol_writers.iter().cloned().collect()),
+        state_file,
         config: Arc::new(config.report()),
         neighbours: Default::default(),
         pulling: Default::default(),
@@ -155,6 +179,11 @@ async fn main() -> Result<()> {
 
     trace!("Application state initialized");
 
+    // Join the remembered swarm and no other; HELLOs claim it.
+    if let Some(remembered) = remembered {
+        state.set_expected_swarm_id(remembered.swarm_id).await?;
+    }
+
     let consumer_state = state.clone();
     tokio::spawn(async move {
         let inner_state = consumer_state.clone();
@@ -205,6 +234,7 @@ async fn main() -> Result<()> {
         ready = state.is_ready().await,
         "Bootstrap completed"
     );
+    swarm::state_file::update(&state, true).await;
 
     let auth_state = AuthState::new(&args.htpasswd);
     let app = api::router(state.clone(), auth_state, args.debug_api);
@@ -223,6 +253,7 @@ async fn main() -> Result<()> {
     });
 
     let server_fut = server_builder.into_future();
+    let stopping = state.clone();
     tokio::pin!(server_fut);
 
     tokio::select! {
@@ -248,6 +279,7 @@ async fn main() -> Result<()> {
     }
 
     info!("HTTP API server stopped");
+    swarm::state_file::update(&stopping, true).await;
     Ok(())
 }