From fb6823b54b43407cde134e66134c0816da877448 Mon Sep 17 00:00:00 2001
From: Dominik Csapak <d.csapak@proxmox.com>
Date: Thu, 7 Oct 2021 14:03:36 +0200
Subject: [PATCH] rest-server: add cleanup_old_tasks

this is a helper that removes task log files that are not referenced
by the task archive anymore

it gets the oldest task archive file, gets the first endtime (the
oldest) and removes all files in the taskdir where the mtime is older
than that

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 proxmox-rest-server/src/worker_task.rs | 58 ++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/proxmox-rest-server/src/worker_task.rs b/proxmox-rest-server/src/worker_task.rs
index 0ac3f431..51394549 100644
--- a/proxmox-rest-server/src/worker_task.rs
+++ b/proxmox-rest-server/src/worker_task.rs
@@ -5,6 +5,7 @@ use std::io::{Read, Write, BufRead, BufReader};
 use std::panic::UnwindSafe;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::{Arc, Mutex};
+use std::time::{SystemTime, Duration};
 
 use anyhow::{bail, format_err, Error};
 use futures::*;
@@ -218,6 +219,63 @@ pub fn rotate_task_log_archive(size_threshold: u64, compress: bool, max_files: O
     logrotate.rotate(size_threshold, None, max_files)
 }
 
+/// removes all task logs that are older than the oldest task entry in the
+/// task archive
+pub fn cleanup_old_tasks(compressed: bool) -> Result<(), Error> {
+    let setup = worker_task_setup()?;
+
+    let _lock = setup.lock_task_list_files(true)?;
+
+    let logrotate = LogRotate::new(&setup.task_archive_fn, compressed)
+            .ok_or_else(|| format_err!("could not get archive file names"))?;
+
+    let mut timestamp = None;
+    if let Some(last_file) = logrotate.files().last() {
+        let reader = BufReader::new(last_file);
+        for line in reader.lines() {
+            let line = line?;
+            if let Ok((_, _, Some(state))) = parse_worker_status_line(&line) {
+                timestamp = Some(state.endtime());
+                break;
+            }
+        }
+    }
+
+    fn get_modified(entry: std::fs::DirEntry) -> Result<SystemTime, std::io::Error> {
+        entry.metadata()?.modified()
+    }
+
+    if let Some(timestamp) = timestamp {
+        let cutoff_time = if timestamp > 0 {
+            SystemTime::UNIX_EPOCH.checked_add(Duration::from_secs(timestamp as u64))
+        } else {
+            SystemTime::UNIX_EPOCH.checked_sub(Duration::from_secs(-timestamp as u64))
+        }.ok_or_else(|| format_err!("could not calculate cutoff time"))?;
+
+        for i in 0..256 {
+            let mut path = setup.taskdir.clone();
+            path.push(format!("{:02X}", i));
+            for file in std::fs::read_dir(path)? {
+                let file = file?;
+                let path = file.path();
+
+                let modified = get_modified(file)
+                    .map_err(|err| format_err!("error getting mtime for {:?}: {}", path, err))?;
+
+                if modified < cutoff_time {
+                    match std::fs::remove_file(path) {
+                        Ok(()) => {},
+                        Err(err) if err.kind() == std::io::ErrorKind::NotFound => {},
+                        Err(err) => bail!("could not remove file: {}", err),
+                    }
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
 
 /// Path to the worker log file
 pub fn upid_log_path(upid: &UPID) -> Result<std::path::PathBuf, Error> {