fix(fuse,core): retry a create at once when a write replaced its blob (B185)

crates/pdfs-core/src/db/ops.rs

@@ -1477,22 +1477,28 @@ impl Db {
     /// Make a create due again if it was renamed or moved
     /// ([`Db::rewrite_op_target`]) while the attempt that just failed was on
     /// the wire, `parent_uid` and `name` being what that attempt sent. What it
-    /// failed on may have been the target it no longer has. Returns whether it
+    /// failed on may have been the target it no longer has. Likewise if a
+    /// write replaced its blob (`blob_path` being the one the attempt read):
+    /// the old one is discarded as the new one attaches, and an attempt that
+    /// had not opened it yet failed on a file that is gone. Returns whether it
     /// was.
     pub fn retry_if_retargeted(
         &self,
         id: i64,
         parent_uid: Option<&str>,
         name: Option<&str>,
+        blob_path: Option<&str>,
     ) -> Result<bool> {
         let conn = self.conn.lock();
         let n = conn.execute(
             &format!(
                 "UPDATE pending_op SET next_attempt_at = 0
                  WHERE id = ?1 AND kind IN (?4, ?5) AND next_attempt_at < ?6
-                   AND ({PARENT_NOW} IS NOT ?2 OR name IS NOT ?3)"
+                   AND ({PARENT_NOW} IS NOT ?2 OR name IS NOT ?3 OR blob_path IS NOT ?7)"
             ),
-            params![id, parent_uid, name, OP_CREATE, OP_MKDIR, PARK_UNTIL],
+            params![
+                id, parent_uid, name, OP_CREATE, OP_MKDIR, PARK_UNTIL, blob_path
+            ],
         )?;
         Ok(n > 0)
     }

crates/pdfs-core/src/db/tests.rs

@@ -2969,7 +2969,8 @@ fn renaming_a_queued_create_rewrites_its_target() {
 
 /// A create that failed on a name held by a queued change waits out a
 /// backoff. Renamed away from that name, it is due again at once; parked, it
-/// stays parked.
+/// stays parked. One whose blob a write replaced as it failed is due again at
+/// once too.
 #[test]
 fn renaming_a_backing_off_create_makes_it_due() {
     let db = Db::open_in_memory().unwrap();
@@ -3011,8 +3012,13 @@ fn renaming_a_backing_off_create_makes_it_due() {
     db.record_op_failure(sent.id, "d is still held", 10_000)
         .unwrap();
     assert!(
-        db.retry_if_retargeted(sent.id, sent.parent_uid.as_deref(), sent.name.as_deref())
-            .unwrap()
+        db.retry_if_retargeted(
+            sent.id,
+            sent.parent_uid.as_deref(),
+            sent.name.as_deref(),
+            sent.blob_path.as_deref()
+        )
+        .unwrap()
     );
     let ops = db.pending_ops().unwrap();
     assert_eq!(
@@ -3023,8 +3029,42 @@ fn renaming_a_backing_off_create_makes_it_due() {
         0
     );
     assert!(
-        !db.retry_if_retargeted(sent.id, sent.parent_uid.as_deref(), Some("f"))
-            .unwrap()
+        !db.retry_if_retargeted(
+            sent.id,
+            sent.parent_uid.as_deref(),
+            Some("f"),
+            sent.blob_path.as_deref()
+        )
+        .unwrap()
+    );
+
+    // A write replaced the blob before the attempt opened it: the old one was
+    // discarded, the attempt failed on a missing file, and the create is due
+    // again at once with the new one (`docs/BUGS.md` B185).
+    db.record_op_failure(sent.id, "No such file or directory", 10_000)
+        .unwrap();
+    db.attach_blob_to_create("local~failed", "/staging/newer", "{}")
+        .unwrap()
+        .expect("the create is still queued");
+    db.record_op_failure(sent.id, "No such file or directory", 10_000)
+        .unwrap();
+    assert!(
+        db.retry_if_retargeted(
+            sent.id,
+            sent.parent_uid.as_deref(),
+            Some("f"),
+            sent.blob_path.as_deref()
+        )
+        .unwrap()
+    );
+    assert!(
+        !db.retry_if_retargeted(
+            sent.id,
+            sent.parent_uid.as_deref(),
+            Some("f"),
+            Some("/staging/newer")
+        )
+        .unwrap()
     );
 }
 

crates/pdfs-fuse/src/drain.rs

@@ -441,9 +441,10 @@ impl Core {
                     op.id,
                     op.parent_uid.as_deref(),
                     op.name.as_deref(),
+                    op.blob_path.as_deref(),
                 ) {
                     Ok(true) => {
-                        debug!(uid = %op.uid, "create was renamed while it failed; retrying")
+                        debug!(uid = %op.uid, "create was renamed or rewritten while it failed; retrying")
                     }
                     Ok(false) => {}
                     Err(e) => {