1 files changed, 114 insertions, 0 deletions
diff --git a/server/blacklist.py b/server/blacklist.py
new file mode 100644
index 0000000..84b8fb2
--- /dev/null
+++ b/server/blacklist.py
@@ -0,0 +1,114 @@
+'''
+    A utility class to manage blacklisted
+    addresses & interact with the database.
+
+    Verified: 2021 February 7
+    * Follows PEP8
+    * Tested Platforms
+        * Windows 10
+'''
+
+from server.database import Database
+from server.error import ServerError
+from server.console import Console
+from shared.state import Static
+
+import ipaddress
+
+
+class Blacklist:
+
+    __TABLE_NAME = 'blacklist'
+    __TABLE_KWARGS = {
+        'address': 'text'
+    }
+
+    def __init__(self, ret):
+        self.__ret = ret
+
+        self.__db = Database()
+        self.__db.create_table(Blacklist.__TABLE_NAME,
+                               **Blacklist.__TABLE_KWARGS)
+        self.__db.commit()
+
+        self.__blacklist = [address[0] for address in
+                            self.__db.read(Blacklist.__TABLE_NAME)]
+
+    @ServerError.quiet
+    def __del__(self):
+        self.__db.close()
+
+    @property
+    def blacklist(self):
+        return self.__blacklist
+
+    def add(self, address):
+        address = self.__verify_address(address)
+
+        if self.__address_exists(address):
+            return Console.printf('Address is already blacklisted',
+                                  Static.WARNING, ret=self.__ret)
+        else:
+            self.__db.write(Blacklist.__TABLE_NAME, (address,))
+            self.__db.commit()
+
+            return Console.printf('Blacklist address added',
+                                  Static.SUCCESS, ret=self.__ret)
+
+    def remove(self, address):
+        address = self.__verify_address(address)
+
+        if self.__address_exists(address):
+            self.__db.delete(Blacklist.__TABLE_NAME,
+                             ('address', '=', address))
+            self.__db.commit()
+
+            return Console.printf('Blacklist address removed',
+                                  Static.SUCCESS, ret=self.__ret)
+        else:
+            return Console.printf('Address is not blacklisted',
+                                  Static.WARNING, ret=self.__ret)
+
+    def update(self, address, new_address):
+        address = self.__verify_address(address)
+        new_address = self.__verify_address(new_address)
+
+        if self.__address_exists(address):
+            if self.__address_exists(new_address):
+                return Console.printf('New address already exists',
+                                      Static.WARNING, ret=self.__ret)
+            else:
+                self.__db.update(Blacklist.__TABLE_NAME,
+                                 ('address', '=', address),
+                                 address=new_address)
+                self.__db.commit()
+                return Console.printf('Blacklist address updated',
+                                      Static.SUCCESS, ret=self.__ret)
+        else:
+            return Console.printf('Address is not blacklisted',
+                                  Static.WARNING, ret=self.__ret)
+
+    def list(self):
+        if self.blacklist:
+            headers, values = ('Address', 'IPV6', 'Link Local',
+                               'Private', 'Loopback'), []
+
+            for address in self.blacklist:
+                address_obj = ipaddress.ip_address(address)
+
+                values.append((str(address_obj),
+                               str(address_obj.version == 6),
+                               str(address_obj.is_link_local),
+                               str(address_obj.is_private),
+                               str(address_obj.is_loopback)))
+
+            return Console.tabulate(values, headers, self.__ret)
+        else:
+            return Console.printf('No addresses blacklisted',
+                                  Static.INFO, ret=self.__ret)
+
+    def __address_exists(self, address):
+        return address in self.blacklist
+
+    def __verify_address(self, address):
+        return str(ipaddress.ip_address(address))