pmb.chroot.init: warn about outdated chroots (MR 2293)

Prepare to remove the outdated chroot check from "pmbootstrap status".
Display it when the user enters a stale chroot instead. This way the
user is more likely to see it, and we can make "pmbootstrap status" more
minimal (by removing all checks, in future patches).

Related: issue 1903

pmb/chroot/init.py

@@ -14,6 +14,7 @@ import pmb.helpers.repo
 import pmb.helpers.run
 import pmb.parse.arch
 
+cache_chroot_is_outdated = []
 
 class UsrMerge(enum.Enum):
     """
@@ -92,6 +93,22 @@ def init_usr_merge(args, suffix):
                                 f"{args.work}/chroot_{suffix}"])
 
 
+def warn_if_chroot_is_outdated(args, suffix):
+    global cache_chroot_is_outdated
+
+    # Only check / display the warning once per session
+    if suffix in cache_chroot_is_outdated:
+        return
+
+    if pmb.config.workdir.chroots_outdated(args, suffix):
+        days_warn = int(pmb.config.chroot_outdated / 3600 / 24)
+        logging.warning(f"WARNING: Your {suffix} chroot is older than"
+                        f" {days_warn} days. Consider running"
+                        " 'pmbootstrap zap'.")
+
+    cache_chroot_is_outdated += [suffix]
+
+
 def init(args, suffix="native", usr_merge=UsrMerge.AUTO,
          postmarketos_mirror=True):
     """
@@ -115,6 +132,7 @@ def init(args, suffix="native", usr_merge=UsrMerge.AUTO,
         pmb.config.workdir.chroot_check_channel(args, suffix)
         copy_resolv_conf(args, suffix)
         pmb.chroot.apk.update_repository_list(args, suffix, postmarketos_mirror)
+        warn_if_chroot_is_outdated(args, suffix)
         return
 
     # Require apk-tools-static

pmb/config/workdir.py

@@ -35,11 +35,15 @@ def chroot_save_init(args, suffix):
         cfg.write(handle)
 
 
-def chroots_outdated(args):
-    """ Check if init dates from workdir.cfg indicate that any chroot is
-        outdated.
-        :returns: True if any of the chroots are outdated and should be zapped,
-                  False otherwise """
+def chroots_outdated(args, suffix=None):
+    """Check if init dates from workdir.cfg indicate that any chroot is
+    outdated.
+
+    :param suffix: only check a specific chroot suffix
+
+    :returns: True if any of the chroots are outdated and should be zapped,
+              False otherwise
+    """
     # Skip if workdir.cfg doesn't exist
     path = args.work + "/workdir.cfg"
     if not os.path.exists(path):
@@ -52,8 +56,10 @@ def chroots_outdated(args):
         return False
 
     date_outdated = time.time() - pmb.config.chroot_outdated
-    for suffix in cfg[key]:
-        date_init = int(cfg[key][suffix])
+    for cfg_suffix in cfg[key]:
+        if suffix and cfg_suffix != suffix:
+            continue
+        date_init = int(cfg[key][cfg_suffix])
         if date_init <= date_outdated:
             return True
     return False