Update the pieces to use base64 encoded binary

data/fields.py

@@ -5,7 +5,10 @@ import json
 from peewee import TextField
 
 
-class ResumableSHA256Field(TextField):
+class _ResumableSHAField(TextField):
+  def _create_sha(self):
+    raise NotImplementedError
+
   def db_value(self, value):
     sha_state = value.state()
 
@@ -16,7 +19,7 @@ class ResumableSHA256Field(TextField):
     return json.dumps(sha_state)
 
   def python_value(self, value):
-    to_resume = resumablehashlib.sha256()
+    to_resume = self._create_sha()
     if value is None:
       return to_resume
 
@@ -28,27 +31,14 @@ class ResumableSHA256Field(TextField):
     return to_resume
 
 
-class ResumableSHA1Field(TextField):
-  def db_value(self, value):
-    sha_state = value.state()
+class ResumableSHA256Field(_ResumableSHAField):
+  def _create_sha(self):
+    return resumablehashlib.sha256()
 
-    # One of the fields is a byte string, let's base64 encode it to make sure
-    # we can store and fetch it regardless of default collocation.
-    sha_state[3] = base64.b64encode(sha_state[3])
 
-    return json.dumps(sha_state)
-
-  def python_value(self, value):
-    to_resume = resumablehashlib.sha1()
-    if value is None:
-      return to_resume
-
-    sha_state = json.loads(value)
-
-    # We need to base64 decode the data bytestring.
-    sha_state[3] = base64.b64decode(sha_state[3])
-    to_resume.set_state(sha_state)
-    return to_resume
+class ResumableSHA1Field(_ResumableSHAField):
+  def _create_sha(self):
+    return resumablehashlib.sha1()
 
 
 class JSONField(TextField):
@@ -59,3 +49,15 @@ class JSONField(TextField):
     if value is None or value == "":
       return {}
     return json.loads(value)
+
+
+class Base64BinaryField(TextField):
+  def db_value(self, value):
+    if value is None:
+      return None
+    return base64.b64encode(value)
+
+  def python_value(self, value):
+    if value is None:
+      return None
+    return base64.b64decode(value)