From be46f3c6378085e7ba9f229390ce72a2caa957d1 Mon Sep 17 00:00:00 2001
From: Ben Adida <ben@adida.net>
Date: Mon, 3 Jan 2011 17:00:44 -0800
Subject: [PATCH] added more datatypes, beginning to build out the data
modularity portion of Helios
---
helios/datatypes/2011/01.py | 13 +++++
helios/datatypes/__init__.py | 83 +++++++++++++++++++++++++++-----
helios/datatypes/core.py | 15 ++++++
helios/datatypes/legacy.py | 32 +++++++++++-
helios/datatypes/pkc/__init__.py | 3 ++
helios/datatypes/pkc/elgamal.py | 21 ++++++++
helios/tests.py | 9 ++--
7 files changed, 160 insertions(+), 16 deletions(-)
create mode 100644 helios/datatypes/core.py
create mode 100644 helios/datatypes/pkc/__init__.py
create mode 100644 helios/datatypes/pkc/elgamal.py
diff --git a/helios/datatypes/2011/01.py b/helios/datatypes/2011/01.py
index a2edc83..ca56479 100644
--- a/helios/datatypes/2011/01.py
+++ b/helios/datatypes/2011/01.py
@@ -4,5 +4,18 @@ data types for 2011/01 Helios
from helios.datatypes import LDObject
+class Trustee(LDObject):
+ """
+ a trustee
+ """
+
+ FIELDS = ['uuid', 'public_key', 'public_key_hash', 'pok', 'decryption_factors', 'decryption_proofs', 'email']
+ STRUCTURED_FIELDS = {
+ 'pok' : 'pkc/elgamal/DiscreteLogProof',
+ 'public_key' : 'pkc/elgamal/PublicKey'
+ }
+
+ # removed some public key processing for now
+
class Election(LDObject):
pass
diff --git a/helios/datatypes/__init__.py b/helios/datatypes/__init__.py
index d336b00..ef8ed01 100644
--- a/helios/datatypes/__init__.py
+++ b/helios/datatypes/__init__.py
@@ -34,7 +34,8 @@ class LDObject(object):
data format. For example, a legacy election LDObject instance will wrap an Election object
and serialize its fields according to the specs for that version.
- To accomodate old JSON types, we allow classes to override default JSON-LD fields.
+ To accomodate old JSON types, we allow classes to do basically whatever they want,
+ or to let this base class serialize pure JSON thingies, without the JSON-LD.
"""
# whether or not to add JSON-LD things
@@ -43,26 +44,56 @@ class LDObject(object):
# fields to serialize
FIELDS = []
+ # structured fields
+ STRUCTURED_FIELDS = {}
+
+ def __init__(self, wrapped_obj):
+ self.wrapped_obj = wrapped_obj
+ self.structured_fields = {}
+
@classmethod
- def instantiate(cls, obj):
- if not hasattr(obj, 'datatype'):
+ def get_class(cls, datatype):
+ # parse datatype string "v31/Election" --> from v31 import Election
+ parsed_datatype = datatype.split("/")
+
+ # get the module
+ dynamic_module = __import__(".".join(parsed_datatype[:-1]), globals(), locals(), [], level=-1)
+
+ # go down the attributes to get to the class
+ dynamic_ptr = dynamic_module
+ for attr in parsed_datatype[1:]:
+ dynamic_ptr = getattr(dynamic_ptr, attr)
+ dynamic_cls = dynamic_ptr
+
+ return dynamic_cls
+
+ @classmethod
+ def instantiate(cls, obj, datatype=None):
+ if hasattr(obj, 'datatype') and not datatype:
+ datatype = getattr(obj, 'datatype')
+
+ if not datatype:
raise Exception("no datatype found")
- # parse datatype string "v31/Election" --> from v31 import Election
- parsed_datatype = obj.datatype.split("/")
+ # the class
+ dynamic_cls = cls.get_class(datatype)
+
+ # instantiate it
+ return_obj = dynamic_cls(obj)
- # construct it
- dynamic_cls = getattr(__import__(".".join(parsed_datatype[:-1]), globals(), locals(), [], level=-1), parsed_datatype[len(parsed_datatype)-1])
+ # go through the subfields and instantiate them too
+ for subfield_name, subfield_type in dynamic_cls.STRUCTURED_FIELDS.iteritems():
+ return_obj.structured_fields[subfield_name] = cls.instantiate(getattr(return_obj.wrapped_obj, subfield_name), datatype = subfield_type)
- return dynamic_cls(obj)
+ return return_obj
def set_from_args(self, **kwargs):
for f in self.FIELDS:
if kwargs.has_key(f):
new_val = self.process_value_in(f, kwargs[f])
- setattr(self, f, new_val)
+ setattr(self.wrapped_obj, f, new_val)
else:
- setattr(self, f, None)
+ setattr(self.wrapped_obj, f, None)
def serialize(self):
return utils.to_json(self.toDict())
@@ -70,17 +101,23 @@ class LDObject(object):
def toDict(self, alternate_fields=None):
val = {}
for f in (alternate_fields or self.FIELDS):
- val[f] = self.process_value_out(f, getattr(self, f))
+ # is it a structured subfield?
+ if self.structured_fields.has_key(f):
+ val[f] = self.structured_fields[f].toDict()
+ else:
+ val[f] = self.process_value_out(f, getattr(self.wrapped_obj, f))
return val
@classmethod
def fromDict(cls, d):
+ raise Exception("not a good idea yet")
+
# go through the keys and fix them
new_d = {}
for k in d.keys():
new_d[str(k)] = d[k]
- return cls(**new_d)
+ return cls(**new_d)
@property
def hash(self):
@@ -125,3 +162,25 @@ class LDObject(object):
return other != None and self.uuid == other.uuid
+
+class ArrayOfObjects(LDObject):
+ """
+ If one type has, as a subtype, an array of things, then this is the structured field used
+ """
+
+ def __init__(self, wrapped_array, item_type):
+ self.item_type = item_type
+ self.items = [LDObject.instantiate(wrapped_item, item_type) for wrapped_item in wrapped_array]
+
+ def toDict(self):
+ return [item.serialize() for item in self.items]
+
+def arrayOf(item_type):
+ """
+ a wrapper for the construtor of the array
+ returns the constructor
+ """
+ def array_constructor(wrapped_array):
+ return ArrayOfObjects(wrapped_array, item_type)
+
+ return array_constructor
diff --git a/helios/datatypes/core.py b/helios/datatypes/core.py
new file mode 100644
index 0000000..c0d488c
--- /dev/null
+++ b/helios/datatypes/core.py
@@ -0,0 +1,15 @@
+"""
+core data types
+"""
+
+from helios.datatypes import LDObject
+
+class BigInteger(LDObject):
+ """
+ A big integer is an integer serialized as a string.
+ We may want to b64 encode here soon.
+ """
+
+ def toDict(self):
+ return str(self.wrapped_obj)
+
diff --git a/helios/datatypes/legacy.py b/helios/datatypes/legacy.py
index 941f15f..1a10de2 100644
--- a/helios/datatypes/legacy.py
+++ b/helios/datatypes/legacy.py
@@ -2,4 +2,34 @@
Legacy datatypes for Helios (v3.0)
"""
-class
+from helios.datatypes import LDObject, arrayOf
+
+class LegacyObject(LDObject):
+ USE_JSON_LD = False
+
+class Election(LegacyObject):
+ FIELDS = ['uuid', 'questions', 'name', 'short_name', 'description', 'voters_hash', 'openreg',
+ 'frozen_at', 'public_key', 'cast_url', 'use_voter_aliases', 'voting_starts_at', 'voting_ends_at']
+
+ STRUCTURED_FIELDS = {
+ 'public_key' : 'legacy/EGPublicKey'
+ }
+
+class EncryptedAnswer(LegacyObject):
+ FIELDS = ['choices', 'individual_proofs', 'overall_proof', 'randomness', 'answer']
+ STRUCTURED_FIELDS = {
+ 'choices': arrayOf('pkc/elgamal/Ciphertext'),
+ 'individual_proofs': arrayOf('pkc/elgamal/DisjunctiveProof'),
+ 'overall_proof' : 'pkc/elgamal/DisjunctiveProof',
+ 'randomness' : 'core/BigInteger'
+ # answer is not a structured field, it's an as-is integer
+ }
+
+class Voter(LegacyObject):
+ pass
+
+class CastVote(LegacyObject):
+ pass
+
+class Trustee(LegacyObject):
+ pass
diff --git a/helios/datatypes/pkc/__init__.py b/helios/datatypes/pkc/__init__.py
new file mode 100644
index 0000000..4783a08
--- /dev/null
+++ b/helios/datatypes/pkc/__init__.py
@@ -0,0 +1,3 @@
+"""
+Public Key Cryptography datatypes
+"""
diff --git a/helios/datatypes/pkc/elgamal.py b/helios/datatypes/pkc/elgamal.py
new file mode 100644
index 0000000..24729e6
--- /dev/null
+++ b/helios/datatypes/pkc/elgamal.py
@@ -0,0 +1,21 @@
+"""
+data types for 2011/01 Helios
+"""
+
+from helios.datatypes import LDObject
+
+class DiscreteLogProof(LDObject):
+ FIELDS = ['challenge', 'commitment', 'response']
+ STRUCTURED_FIELDS = {
+ 'challenge' : 'core/BigInteger',
+ 'commitment' : 'core/BigInteger',
+ 'response' : 'core/BigInteger'}
+
+class PublicKey(LDObject):
+ FIELDS = ['y', 'p', 'g', 'q']
+ STRUCTURED_FIELDS = {
+ 'y' : 'core/BigInteger',
+ 'p' : 'core/BigInteger',
+ 'g' : 'core/BigInteger',
+ 'q' : 'core/BigInteger'}
+
diff --git a/helios/tests.py b/helios/tests.py
index a6e5252..7838baf 100644
--- a/helios/tests.py
+++ b/helios/tests.py
@@ -98,7 +98,7 @@ class ElectionModelTests(TestCase):
self.assertTrue(self.election.has_helios_trustee())
- trustee = self.election.get_helios_trustee()
+ trustee = self.election.get_helios_trustee()
self.assertNotEquals(trustee, None)
def test_log(self):
@@ -221,10 +221,13 @@ class DatatypeTests(TestCase):
def setUp(self):
self.election = models.Election.objects.all()[0]
+ self.election.generate_trustee(ELGAMAL_PARAMS)
def test_instantiate(self):
- ld_obj = datatypes.LDObject.instantiate(self.election)
-
+ ld_obj = datatypes.LDObject.instantiate(self.election.get_helios_trustee(), '2011/01/Trustee')
+ foo = ld_obj.serialize()
+
+
##
## Black box tests
--
GitLab