[ci skip] Fix registry tag cleanup for pull-through cache

- Rewrite cleanup script to use filesystem deletion (shutil.rmtree)
  since proxy registries don't support DELETE via API (405)
- Fix cron entry to invoke with python3

main.tf

@@ -281,7 +281,7 @@ module "docker-registry-template" {
     format("echo %s | base64 -d > /etc/docker-registry/cleanup-tags.sh && chmod +x /etc/docker-registry/cleanup-tags.sh",
       base64encode(file("${path.root}/modules/docker-registry/cleanup-tags.sh"))
     ),
-    "( crontab -l 2>/dev/null; echo '0 2 * * * /etc/docker-registry/cleanup-tags.sh 10 >> /var/log/registry-cleanup.log 2>&1' ) | crontab -",
+    "( crontab -l 2>/dev/null; echo '0 2 * * * python3 /etc/docker-registry/cleanup-tags.sh 10 >> /var/log/registry-cleanup.log 2>&1' ) | crontab -",
   ]
 }
 

modules/docker-registry/cleanup-tags.sh

@@ -1,72 +1,48 @@
 #!/usr/bin/env python3
-"""Keeps only the N most recent tags per image in a Docker registry.
-Uses filesystem modification times on the tag directories for speed.
-Run garbage-collect after this to reclaim disk space."""
+"""Keeps only the N most recent tags per image in a pull-through cache registry.
+Deletes old tag links directly from the filesystem since the API doesn't support
+DELETE on proxy registries. Run garbage-collect after to reclaim blob storage."""
 
-import json
 import os
+import shutil
 import sys
-import urllib.request
 
 sys.stdout.reconfigure(line_buffering=True)
 
-REGISTRY = "http://127.0.0.1:5000"
 KEEP = int(sys.argv[1]) if len(sys.argv) > 1 else 10
 
-# Registry storage path (docker volume)
 STORAGE = "/var/lib/docker/volumes/57b3f1c5fcc7f39c040e17072e10b4536245357d09340206683c04096d30b942/_data/docker/registry/v2/repositories"
 
-def api(path, method="GET", headers=None):
-    req = urllib.request.Request(f"{REGISTRY}{path}", method=method, headers=headers or {})
-    try:
-        with urllib.request.urlopen(req, timeout=30) as r:
-            if method == "HEAD":
-                return dict(r.headers)
-            return json.loads(r.read())
-    except Exception:
-        return None
-
-# Get all repos
-catalog = api("/v2/_catalog")
-if not catalog:
-    print("Failed to fetch catalog")
-    sys.exit(1)
-
 total_deleted = 0
 
-for repo in catalog.get("repositories", []):
-    tags_dir = os.path.join(STORAGE, repo, "_manifests", "tags")
-    if not os.path.isdir(tags_dir):
+for root, dirs, _ in os.walk(STORAGE):
+    # Look for _manifests/tags directories
+    if not root.endswith("_manifests/tags"):
         continue
 
-    # Get tags with their modification times from filesystem
+    repo = root.replace(STORAGE + "/", "").replace("/_manifests/tags", "")
+
+    # Get tags with modification times
     tag_times = []
-    for tag in os.listdir(tags_dir):
-        tag_path = os.path.join(tags_dir, tag)
+    for tag in os.listdir(root):
+        tag_path = os.path.join(root, tag)
         if os.path.isdir(tag_path):
             mtime = os.path.getmtime(tag_path)
-            tag_times.append((mtime, tag))
+            tag_times.append((mtime, tag, tag_path))
 
     if len(tag_times) <= KEEP:
         continue
 
-    # Sort by mtime descending (newest first), delete everything past KEEP
+    # Sort by mtime descending (newest first)
     tag_times.sort(reverse=True)
     to_delete = tag_times[KEEP:]
 
-    print(f"[{repo}] has {len(tag_times)} tags, deleting {len(to_delete)}, keeping {KEEP}")
+    print(f"[{repo}] {len(tag_times)} tags -> keeping {KEEP}, deleting {len(to_delete)}")
 
-    for _, tag in to_delete:
-        headers_resp = api(f"/v2/{repo}/manifests/{tag}", method="HEAD", headers={
-            "Accept": "application/vnd.docker.distribution.manifest.v2+json"
-        })
-        if not headers_resp:
-            continue
-        digest = headers_resp.get("Docker-Content-Digest") or headers_resp.get("docker-content-digest")
-        if digest:
-            result = api(f"/v2/{repo}/manifests/{digest}", method="DELETE")
-            total_deleted += 1
+    for _, tag, tag_path in to_delete:
+        shutil.rmtree(tag_path)
+        total_deleted += 1
 
-    print(f"  deleted {len(to_delete)} tags")
+    print(f"  done")
 
-print(f"\nDone. Deleted {total_deleted} total tags. Run garbage-collect to reclaim disk space.")
+print(f"\nDeleted {total_deleted} tags. Restart registry and run garbage-collect to reclaim space.")