Crono expression parser fix (#1682)

examples/server_container.toml

@@ -102,6 +102,10 @@ origin = "https://idm.example.com:8443"
 # schedule = "00 22 * * *"
 #    four times a day at 3 minutes past the hour, every 6th hours
 # schedule = "03 */6 * * *"
+#   We also support non standard cron syntax, with the following format:
+#   sec  min   hour   day of month   month   day of week   year
+#   (it's very similar to the standard cron syntax, it just allows to specify the seconds
+#   at the beginning and the year at the end)
 #   Number of backups to keep (default 7)
 # versions = 7
 #

server/core/src/interval.rs

@@ -56,17 +56,33 @@ impl IntervalActor {
     #[allow(clippy::result_unit_err)]
     pub fn start_online_backup(
         server: &'static QueryServerReadV1,
-        cfg: &OnlineBackup,
+        online_backup_config: &OnlineBackup,
         mut rx: broadcast::Receiver<CoreAction>,
     ) -> Result<tokio::task::JoinHandle<()>, ()> {
-        let outpath = cfg.path.to_owned();
-        let versions = cfg.versions;
-
+        let outpath = online_backup_config.path.to_owned();
+        let versions = online_backup_config.versions;
+        let crono_expr = online_backup_config.schedule.as_str().to_string();
+        let mut crono_expr_values = crono_expr.split_ascii_whitespace().collect::<Vec<&str>>();
+        let chrono_expr_uses_standard_syntax = crono_expr_values.len() == 5;
+        if chrono_expr_uses_standard_syntax {
+            // we add a 0 element at the beginning to simulate the standard crono syntax which always runs
+            // commands at seconds 00
+            crono_expr_values.insert(0, "0");
+            crono_expr_values.push("*");
+        }
+        let crono_expr_schedule = crono_expr_values.join(" ");
+        if chrono_expr_uses_standard_syntax {
+            info!(
+                "Provided online backup schedule is: {}, now being transformed to: {}",
+                crono_expr, crono_expr_schedule
+            );
+        }
         // Cron expression handling
-        let cron_expr = Schedule::from_str(cfg.schedule.as_str()).map_err(|e| {
+        let cron_expr = Schedule::from_str(crono_expr_schedule.as_str()).map_err(|e| {
             error!("Online backup schedule parse error: {}", e);
             error!("valid formats are:");
             error!("sec  min   hour   day of month   month   day of week   year");
+            error!("min   hour   day of month   month   day of week");
             error!("@hourly | @daily | @weekly");
         })?;
 

server/core/src/lib.rs

@@ -739,9 +739,12 @@ pub async fn create_server_core(
     let interval_handle = IntervalActor::start(server_write_ref, broadcast_tx.subscribe());
     // Setup timed events associated to the read thread
     let maybe_backup_handle = match &config.online_backup {
-        Some(cfg) => {
-            let handle =
-                IntervalActor::start_online_backup(server_read_ref, cfg, broadcast_tx.subscribe())?;
+        Some(online_backup_config) => {
+            let handle = IntervalActor::start_online_backup(
+                server_read_ref,
+                online_backup_config,
+                broadcast_tx.subscribe(),
+            )?;
             Some(handle)
         }
         None => {