Restore has_synced on iteration start

Author: simolus3

crates/core/src/sync/storage_adapter.rs

@@ -10,7 +10,10 @@ use crate::{
     operations::delete_bucket,
     schema::Schema,
     state::DatabaseState,
-    sync::checkpoint::{validate_checkpoint, ChecksumMismatch},
+    sync::{
+        checkpoint::{validate_checkpoint, ChecksumMismatch},
+        sync_status::SyncPriorityStatus,
+    },
     sync_local::{PartialSyncOperation, SyncOperation},
 };
 
@@ -68,6 +71,32 @@ impl StorageAdapter {
         Ok(requests)
     }
 
+    pub fn collect_sync_state(&self) -> Result<Vec<SyncPriorityStatus>, PowerSyncError> {
+        // language=SQLite
+        let statement = self
+            .db
+            .prepare_v2(
+                "SELECT priority, unixepoch(last_synced_at) FROM ps_sync_state ORDER BY priority",
+            )
+            .into_db_result(self.db)?;
+
+        let mut items = Vec::<SyncPriorityStatus>::new();
+        while statement.step()? == ResultCode::ROW {
+            let priority = BucketPriority {
+                number: statement.column_int(0),
+            };
+            let timestamp = statement.column_int64(1);
+
+            items.push(SyncPriorityStatus {
+                priority,
+                last_synced_at: Some(Timestamp(timestamp)),
+                has_synced: Some(true),
+            });
+        }
+
+        return Ok(items);
+    }
+
     pub fn delete_buckets<'a>(
         &self,
         buckets: impl IntoIterator<Item = &'a str>,

crates/core/src/sync/streaming_sync.rs

@@ -577,8 +577,11 @@ impl StreamingSyncIteration {
             ));
         };
 
-        self.status
-            .update(|s| s.start_connecting(), &mut event.instructions);
+        let sync_state = self.adapter.collect_sync_state()?;
+        self.status.update(
+            move |s| s.start_connecting(sync_state),
+            &mut event.instructions,
+        );
 
         let requests = self.adapter.collect_bucket_requests()?;
         let local_bucket_names: Vec<String> = requests.iter().map(|s| s.name.clone()).collect();

crates/core/src/sync/sync_status.rs

@@ -46,10 +46,12 @@ impl DownloadSyncStatus {
         self.downloading = None;
     }
 
-    pub fn start_connecting(&mut self) {
+    pub fn start_connecting(&mut self, status: Vec<SyncPriorityStatus>) {
         self.connected = false;
         self.downloading = None;
         self.connecting = true;
+        self.priority_status = status;
+        self.debug_assert_priority_status_is_sorted();
     }
 
     pub fn mark_connected(&mut self) {
@@ -161,9 +163,9 @@ pub struct Timestamp(pub i64);
 
 #[derive(Serialize, Hash)]
 pub struct SyncPriorityStatus {
-    priority: BucketPriority,
-    last_synced_at: Option<Timestamp>,
-    has_synced: Option<bool>,
+    pub priority: BucketPriority,
+    pub last_synced_at: Option<Timestamp>,
+    pub has_synced: Option<bool>,
 }
 
 /// Per-bucket download progress information.

dart/test/sync_test.dart

@@ -301,6 +301,46 @@ void _syncTests<T>({
     }
   });
 
+  syncTest('remembers sync state', (controller) {
+    invokeControl('start', null);
+
+    pushCheckpoint(buckets: priorityBuckets);
+    pushCheckpointComplete();
+
+    controller.elapse(Duration(minutes: 10));
+    pushCheckpoint(buckets: priorityBuckets);
+    pushCheckpointComplete(priority: 2);
+    invokeControl('stop', null);
+
+    final instructions = invokeControl('start', null);
+    expect(
+      instructions,
+      contains(
+        containsPair(
+          'UpdateSyncStatus',
+          containsPair(
+            'status',
+            containsPair(
+              'priority_status',
+              [
+                {
+                  'priority': 2,
+                  'last_synced_at': 1740823800,
+                  'has_synced': true
+                },
+                {
+                  'priority': 2147483647,
+                  'last_synced_at': 1740823200,
+                  'has_synced': true
+                },
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  });
+
   test('clearing database clears sync status', () {
     invokeControl('start', null);
     pushCheckpoint(buckets: priorityBuckets);