feat(upgrade): implement seamless json to mongodb migration

core/scripts/db/migrate_users.py

@@ -0,0 +1,70 @@
+import json
+from pathlib import Path
+import sys
+import os
+
+sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
+from db.database import db
+
+def migrate():
+    users_json_path = Path("/etc/hysteria/users.json")
+    
+    if not users_json_path.exists():
+        print("users.json not found, no migration needed.")
+        return
+
+    if db is None:
+        print("Error: Database connection failed. Cannot perform migration.", file=sys.stderr)
+        sys.exit(1)
+
+    try:
+        with users_json_path.open('r') as f:
+            users_data = json.load(f)
+    except (json.JSONDecodeError, IOError) as e:
+        print(f"Error reading or parsing users.json: {e}", file=sys.stderr)
+        sys.exit(1)
+
+    print(f"Found {len(users_data)} users in users.json to migrate.")
+    migrated_count = 0
+
+    for username, data in users_data.items():
+        try:
+            user_doc = {
+                "_id": username.lower(),
+                "password": data.get("password"),
+                "max_download_bytes": data.get("max_download_bytes", 0),
+                "expiration_days": data.get("expiration_days", 0),
+                "account_creation_date": data.get("account_creation_date"),
+                "blocked": data.get("blocked", False),
+                "unlimited_user": data.get("unlimited_user", False),
+                "status": data.get("status", "Offline"),
+                "upload_bytes": data.get("upload_bytes", 0),
+                "download_bytes": data.get("download_bytes", 0),
+            }
+            
+            if user_doc["password"] is None:
+                print(f"Warning: User '{username}' has no password, skipping.", file=sys.stderr)
+                continue
+
+            db.collection.update_one(
+                {'_id': user_doc['_id']},
+                {'$set': user_doc},
+                upsert=True
+            )
+            migrated_count += 1
+            print(f"  - Migrated user: {username}")
+        
+        except Exception as e:
+            print(f"Error migrating user '{username}': {e}", file=sys.stderr)
+
+    print(f"Migration complete. {migrated_count} users successfully migrated to MongoDB.")
+    
+    try:
+        migrated_file_path = users_json_path.with_name("users.json.migrated")
+        users_json_path.rename(migrated_file_path)
+        print(f"Renamed old user file to: {migrated_file_path}")
+    except OSError as e:
+        print(f"Warning: Could not rename users.json: {e}", file=sys.stderr)
+
+if __name__ == "__main__":
+    migrate()