feat(storage): clear inactive transfer cache

crates/vnidrop/CORE_FLOW.md

@@ -91,6 +91,11 @@ or temporary tag. Receive downloads keep a temporary tag through export and beco
 reclaimable after publication. Restart reconciliation repairs active-share tags,
 removes orphan share tags, and never restores a stopped share.
 
+The explicit transfer-cache action is available only when no transfer or share is
+active. It shuts the core down cleanly, removes the app-owned blob store, and then
+restarts the core with the same identity and network configuration. Deleting all
+transfer records invokes the same cleanup after live shares have been stopped.
+
 ## Resource Limits
 
 `CoreLimits` controls source count, collection files and bytes, path and ticket

crates/vnidrop/src/api.rs

@@ -2,8 +2,9 @@ use anyhow::Context;
 use iroh::RelayUrl;
 use iroh_blobs::Hash;
 use serde::{Deserialize, Serialize};
-use std::{collections::BTreeSet, net::IpAddr, str::FromStr};
+use std::{collections::BTreeSet, net::IpAddr, path::PathBuf, str::FromStr};
 
+use crate::error::VnidropError;
 use crate::util::{non_empty, now_ms};
 
 pub(crate) const MAX_CUSTOM_RELAYS: usize = 8;
@@ -126,6 +127,49 @@ pub fn default_core_network_config() -> CoreNetworkConfig {
     CoreNetworkConfig::default()
 }
 
+/// Removes the blob store after its owning core has shut down.
+///
+/// Callers must verify that no transfer or share is active before shutdown.
+#[uniffi::export]
+pub fn clear_inactive_transfer_cache(app_data_dir: String) -> Result<u64, VnidropError> {
+    let result = (|| -> anyhow::Result<u64> {
+        let app_data_dir = PathBuf::from(app_data_dir);
+        anyhow::ensure!(
+            app_data_dir.is_absolute(),
+            "app data directory must be absolute"
+        );
+        anyhow::ensure!(
+            app_data_dir.file_name().is_some(),
+            "app data directory must not be a filesystem root"
+        );
+        let blobs = app_data_dir.join("blobs");
+        let metadata = match std::fs::symlink_metadata(&blobs) {
+            Ok(metadata) => metadata,
+            Err(error) if error.kind() == std::io::ErrorKind::NotFound => return Ok(0),
+            Err(error) => return Err(error.into()),
+        };
+        anyhow::ensure!(
+            metadata.is_dir() && !metadata.file_type().is_symlink(),
+            "blob store path is not a directory"
+        );
+        let bytes = walkdir::WalkDir::new(&blobs)
+            .follow_links(false)
+            .into_iter()
+            .try_fold(0u64, |total, entry| {
+                let entry = entry?;
+                let metadata = entry.metadata()?;
+                Ok::<_, walkdir::Error>(if metadata.is_file() {
+                    total.saturating_add(metadata.len())
+                } else {
+                    total
+                })
+            })?;
+        std::fs::remove_dir_all(blobs)?;
+        Ok(bytes)
+    })();
+    result.map_err(VnidropError::filesystem)
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize, uniffi::Record)]
 pub struct CoreLimits {
     pub max_sources: u64,

crates/vnidrop/src/lib.rs

@@ -14,11 +14,11 @@ mod transfer_state;
 mod util;
 
 pub use api::{
-    default_core_limits, default_core_network_config, CoreEvent, CoreEventSink, CoreLimits,
-    CoreNetworkConfig, CoreRelayMode, CoreStorageUsage, PublishedOutput, ReceiveOutputSink,
-    ReceiveOutputSinkV2, ReceivedArtifact, ReceivedLocatorKind, ReceiverRequest, RuntimeStatus,
-    ShareMetadataInput, ShareResult, ShareSource, SourceKind, StoredTransfer, TicketInspection,
-    TransferAccessMode, TransferMetadata,
+    clear_inactive_transfer_cache, default_core_limits, default_core_network_config, CoreEvent,
+    CoreEventSink, CoreLimits, CoreNetworkConfig, CoreRelayMode, CoreStorageUsage, PublishedOutput,
+    ReceiveOutputSink, ReceiveOutputSinkV2, ReceivedArtifact, ReceivedLocatorKind, ReceiverRequest,
+    RuntimeStatus, ShareMetadataInput, ShareResult, ShareSource, SourceKind, StoredTransfer,
+    TicketInspection, TransferAccessMode, TransferMetadata,
 };
 pub use error::VnidropError;
 pub use runtime::VnidropCore;

crates/vnidrop/tests/storage.rs

@@ -0,0 +1,26 @@
+use vnidrop::clear_inactive_transfer_cache;
+
+#[test]
+fn inactive_transfer_cache_is_removed_and_reports_reclaimed_bytes() {
+    let app_data = tempfile::tempdir().unwrap();
+    let blobs = app_data.path().join("blobs");
+    std::fs::create_dir_all(blobs.join("data")).unwrap();
+    std::fs::write(blobs.join("data").join("payload"), vec![9u8; 4096]).unwrap();
+    std::fs::write(blobs.join("blobs.db"), vec![3u8; 512]).unwrap();
+
+    let reclaimed =
+        clear_inactive_transfer_cache(app_data.path().to_string_lossy().into_owned()).unwrap();
+
+    assert_eq!(reclaimed, 4608);
+    assert!(!blobs.exists());
+}
+
+#[test]
+fn inactive_transfer_cache_rejects_relative_app_data_paths() {
+    assert!(clear_inactive_transfer_cache("relative/path".to_string()).is_err());
+}
+
+#[test]
+fn inactive_transfer_cache_rejects_filesystem_roots() {
+    assert!(clear_inactive_transfer_cache(std::path::MAIN_SEPARATOR_STR.to_string()).is_err());
+}