[PATCH datacenter-manager 04/15] task cache: rotate: align timestamp for new files to UTC midnight

[Lukas Wagner <l.wagner@proxmox.com>]

This also requires to change the rotation check to an inclusive >=,
otherwise we would only rotate after two days instead of every day.

Signed-off-by: Lukas Wagner <l.wagner@proxmox.com>
---
 server/src/remote_tasks/refresh_task.rs | 23 ++++++++++++++++++++++-
 server/src/remote_tasks/task_cache.rs   |  3 ++-
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/server/src/remote_tasks/refresh_task.rs b/server/src/remote_tasks/refresh_task.rs
index 68ef5a25..55d5694e 100644
--- a/server/src/remote_tasks/refresh_task.rs
+++ b/server/src/remote_tasks/refresh_task.rs
@@ -360,7 +360,13 @@ fn get_remotes_with_finished_tasks(
 ///
 /// Returns Ok(true) the cache's files were rotated.
 async fn rotate_cache(cache: TaskCache) -> Result<bool, Error> {
-    tokio::task::spawn_blocking(move || cache.write()?.rotate(proxmox_time::epoch_i64())).await?
+    tokio::task::spawn_blocking(move || {
+        cache.write()?.rotate(align_timestamp(
+            proxmox_time::epoch_i64(),
+            super::ROTATE_AFTER as i64,
+        ))
+    })
+    .await?
 }
 
 /// Apply the task cache journal.
@@ -541,3 +547,18 @@ async fn update_task_cache(
     })
     .await?
 }
+
+/// Align a UNIX timestamp to the specified interval.
+fn align_timestamp(now: i64, interval: i64) -> i64 {
+    now - (now.rem_euclid(interval))
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::remote_tasks::refresh_task::align_timestamp;
+
+    #[test]
+    fn test_align_timestamp() {
+        assert_eq!(align_timestamp(1782898009, 24 * 3600), 1782864000);
+    }
+}
diff --git a/server/src/remote_tasks/task_cache.rs b/server/src/remote_tasks/task_cache.rs
index b5fc3b21..55aa8b70 100644
--- a/server/src/remote_tasks/task_cache.rs
+++ b/server/src/remote_tasks/task_cache.rs
@@ -285,7 +285,8 @@ impl WritableTaskCache {
 
         match archive_files.first() {
             Some(bound) => {
-                if now > bound.starttime && now - bound.starttime > self.cache.rotate_after as i64 {
+                if now > bound.starttime && now - bound.starttime >= self.cache.rotate_after as i64
+                {
                     start_new_file(&mut archive_files)?;
                 }
             }
-- 
2.47.3