fields: Move all custom fields to specific file

Keep things modular.

Signed-off-by: Stephen Finucane <stephen.finucane@intel.com>
Reviewed-by: Andy Doan <andy.doan@linaro.org>

1 files changed, 64 insertions, 0 deletions

diff --git a/patchwork/fields.py b/patchwork/fields.py
new file mode 100644
index 0000000..96fdd28
--- /dev/null
+++ b/patchwork/fields.py
@@ -0,0 +1,64 @@
+# Patchwork - automated patch tracking system
+# Copyright (C) 2008 Jeremy Kerr <jk@ozlabs.org>
+# Copyright (C) 2015 Intel Corporation
+#
+# This file is part of the Patchwork package.
+#
+# Patchwork 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 2 of the License, or
+# (at your option) any later version.
+#
+# Patchwork 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 Patchwork; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+from __future__ import absolute_import
+
+import django
+from django.db import models
+from django.utils import six
+
+
+if django.VERSION < (1, 8):
+    HashFieldBase = six.with_metaclass(models.SubfieldBase, models.CharField)
+else:
+    HashFieldBase = models.CharField
+
+
+class HashField(HashFieldBase):
+
+    def __init__(self, algorithm='sha1', *args, **kwargs):
+        self.algorithm = algorithm
+        try:
+            import hashlib
+
+            def _construct(string=''):
+                if isinstance(string, six.text_type):
+                    string = string.encode('utf-8')
+                return hashlib.new(self.algorithm, string)
+            self.construct = _construct
+            self.n_bytes = len(hashlib.new(self.algorithm).hexdigest())
+        except ImportError:
+            modules = {'sha1': 'sha', 'md5': 'md5'}
+
+            if algorithm not in modules:
+                raise NameError("Unknown algorithm '%s'" % algorithm)
+
+            self.construct = __import__(modules[algorithm]).new
+
+        self.n_bytes = len(self.construct().hexdigest())
+
+        kwargs['max_length'] = self.n_bytes
+        super(HashField, self).__init__(*args, **kwargs)
+
+    def from_db_value(self, value, expression, connection, context):
+        return self.to_python(value)
+
+    def db_type(self, connection=None):
+        return 'char(%d)' % self.n_bytes