Add script to remove old seen messages

cmdeploy/src/cmdeploy/__init__.py

@@ -361,6 +361,14 @@ def _configure_dovecot(config: Config, debug: bool = False) -> bool:
         config=config,
     )
 
+    files.put(
+            src=importlib.resources.files(__package__).joinpath("dovecot/remove-seen.py"),
+            dest="/usr/local/bin/remove-seen.py",
+            user="root",
+            group="root",
+            mode="755"
+    )
+
     # as per https://doc.dovecot.org/configuration_manual/os/
     # it is recommended to set the following inotify limits
     for name in ("max_user_instances", "max_user_watches"):

cmdeploy/src/cmdeploy/dovecot/expunge.cron.j2

@@ -9,3 +9,4 @@
 2 0 * * * vmail find /home/vmail/mail/{{ config.mail_domain }} -path '*/tmp/*' -mtime +{{ config.delete_mails_after }} -type f -delete
 2 0 * * * vmail find /home/vmail/mail/{{ config.mail_domain }} -path '*/.*/tmp/*' -mtime +{{ config.delete_mails_after }} -type f -delete
 3 0 * * * vmail find /home/vmail/mail/{{ config.mail_domain }} -name 'maildirsize' -type f -delete
+4 0 * * * vmail /usr/local/bin/remove-seen.py /home/vmail/mail/{{ config.mail_domain }}

cmdeploy/src/cmdeploy/dovecot/remove-seen.py

@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+"""Remove seen messages that are older than two days
+if maildir has more than 80 MB of messages."""
+import sys
+import time
+from pathlib import Path
+
+
+def getdirsize(path):
+    return sum(f.stat().st_size for f in path.glob("**/*") if f.is_file())
+
+
+def parse_dovecot_seen(path):
+    return "S" in path.name.split(":2,")[-1]
+
+
+def main():
+    now = time.time()
+
+    mailhome = Path(sys.argv[1])
+
+    for p in mailhome.iterdir():
+        dirsize = getdirsize(p / "cur") + getdirsize(p / "new")
+        if dirsize < 80000000:
+            continue
+
+        removed_bytes = 0
+        for mailpath in (p / "cur").iterdir():
+            seen = parse_dovecot_seen(mailpath)
+            stat = mailpath.stat()
+            size = stat.st_size
+            if seen and now > stat.st_mtime + 2 * 24 * 3600:
+                removed_bytes += size
+                mailpath.unlink(missing_ok=True)
+
+        if removed_bytes > 0:
+            (p / "maildirsize").unlink(missing_ok=True)
+
+
+if __name__ == "__main__":
+    main()