Click common validators for CLI module

nucypher/cli/types.py

@@ -0,0 +1,48 @@
+"""
+This file is part of nucypher.
+
+nucypher is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+nucypher is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with nucypher.  If not, see <https://www.gnu.org/licenses/>.
+"""
+
+from ipaddress import ip_address
+
+import click
+from eth_utils import is_checksum_address
+
+
+class ChecksumAddress(click.ParamType):
+    name = 'checksum_address'
+
+    def convert(self, value, param, ctx):
+        if is_checksum_address(value):
+            return value
+        self.fail('{} is not a valid EIP-55 checksum address'.format(value, param, ctx))
+
+
+class IPv4Address(click.ParamType):
+    name = 'ipv4_address'
+
+    def convert(self, value, param, ctx):
+        try:
+            _address = ip_address(value)
+        except ValueError as e:
+            self.fail(str(e))
+        else:
+            return value
+
+
+IPV4_ADDRESS = IPv4Address()
+CHECKSUM_ADDRESS = ChecksumAddress()
+
+