def decrypt(self, key, serialization=SERIALIZATION.TURTLE):
'''
Decrypt with SessionKey.
Using encrypted string to recover the original Object.
@return a new Obj decrypted from cipertext, without those additional types like EncryptedReference and Reference, which
were inserted by encrypt() method before.
'''
if self.encryptedStringRepresentation is not None:
if isinstance(key, RSA._RSAobj):
decryptedString, symkey = SmartAPICrypto().asymmetricDecrypt(
key, self.encryptedStringRepresentation)
else:
decryptedString = SmartAPICrypto().symmetricDecrypt(
key, self.encryptedStringRepresentation)
model = Tools().fromString(decryptedString, serialization)
# find the resource which was encrypted
rootRes = Tools().getTopNode(model)[0]
# figure out its SMARTAPI Class
seasCls = Tools().getResourceClass(rootRes)
# recover it to Obj or its subclass Object
recoveredObj = seasCls.parse(rootRes)
# remove EncryptedReference and Reference types.
recoveredObj.types.remove(URIRef(RESOURCE.ENCRYPTEDREFERENCE))
recoveredObj.types.remove(URIRef(RESOURCE.REFERENCE))
self.__dict__.update(recoveredObj.__dict__)
return recoveredObj
else:
pass
def fetchFromTransactionServer(cls, senderId, notary, *args):
'''
@param senderId: URI string
@param notary: URI string
@param args: a variable number of Transaction Objects
@return a dictionary, key is SeasIdentifierUri of each transaction, value is Transaction Object
'''
try:
client = HttpClient()
# create an empty MIME multipart message
sentHttpMessage = HttpMessage()
# main request
req = RequestFactory().create(senderId)
req.setMethod(RESOURCE.READ)
cls.messageIdCounter = cls.messageIdCounter + 1
req.setMessageId(cls.messageIdCounter)
a = Activity()
req.addActivity(a)
i = Input()
a.addInput(i)
system = SystemOfInterest()
system.setSameAs(notary)
i.setSystemOfInterest(system)
param = Parameter()
param.setKey("transactions")
param.setName("Transaction id list")
param.setDescription(
"List of ids of transactions that are sent to be fetched the database."
)
for transaction in args:
param.addValue(transaction.getIdentifierUri())
i.addParameter(param)
# save Request object to multipart message, Main part
mainRequestString = Tools.toString(req)
sentHttpMessage.addMainpart(mainRequestString)
mainRequestHash = SmartAPICrypto().createEncodedMessageDigest(
mainRequestString)
requestSignature = SmartAPICrypto().sign(
CryptoKeyWallet.getPrivateKey(), mainRequestHash)
#create transaction for the main request
if cls.transactionIdentifierUriPrefix == '':
transactionIdentifierUri = senderId + uuid.uuid4().get_hex()
else:
transactionIdentifierUri = transactionIdentifierUri + uuid.uuid4(
).get_hex()
requestTransaction = Factory.createTransaction(
transactionIdentifierUri, senderId)
requestTransaction.setSigner(senderId)
requestTransactionMessage = Message()
requestTransactionMessage.setMessageId(req.getMessageId())
requestTransactionMessage.setHashCode(mainRequestHash)
requestTransactionMessage.setSignature(requestSignature)
requestTransaction.setMessage(requestTransactionMessage)
# add requestTransaction to multipart message, non-Main part
requestTransactionString = Tools.toString(requestTransaction)
sentHttpMessage.add(transactionIdentifierUri,
requestTransactionString)
# add transactions that are sent to multipart message, non-Main part
for trans in args:
sentHttpMessage.add(trans.getIdentifierUri(),
Tools.toString(trans))
# send out this multipart message
payload = removeFrontHeader(sentHttpMessage.asString())
resp, contentType = client.sendPost(
notary, payload, sentHttpMessage.getContentType())
receivedHttpMessagestr = addFrontHeader(resp, contentType)
receivedHttpMessage = parseMIMEmessage(receivedHttpMessagestr)
map = {}
if isinstance(receivedHttpMessage, HttpMessageSingle):
non_main_parts_dict = {}
else:
non_main_parts_dict = receivedHttpMessage.getNonMainPartsAsDict(
)
counter = 0
for part in non_main_parts_dict.values():
counter = counter + 1
# recover the part from string to Seas Obj
model = Tools().fromString(part, SERIALIZATION.TURTLE)
rootRes = Tools().getTopNode(model)[0]
seasCls = Tools().getResourceClass(rootRes)
recoveredObj = seasCls.parse(rootRes)
if isinstance(
recoveredObj, Transaction
): # We want to save the Transaction that hold the requested data
map[recoveredObj.getIdentifierUri()] = recoveredObj
return map
except:
traceback.print_exc()
def parseStatement(self, statement):
'''
It takes in statement as input, add property to existing model Class object.
Return None
'''
from SmartAPI.model.Parameter import Parameter
from SmartAPI.model.Provenance import Provenance
from SmartAPI.model.Activity import Activity
from SmartAPI.model.Offering import Offering
# get predicate and object
predicate = str(statement.getPredicate())
objectNode = statement.getObject()
# type
if predicate == PROPERTY.RDF_TYPE:
self.addType(URIRef(statement.getResource().toString()))
return
# sameas
if predicate == PROPERTY.SAMEAS:
self.setSameAs(statement.getResource().toString())
return
# generatedby
if predicate == PROPERTY.GENERATEDBY:
self.setGeneratedBy(Activity.parse(statement.getResource()))
return
# generatedat
if predicate == PROPERTY.GENERATEDAT:
self.setGeneratedAt(statement.getObject().toPython())
return
# provenance
if predicate == PROPERTY.PROVENANCE:
self.addProvenance(Provenance.parse(statement.getResource()))
return
# offerings
if predicate == PROPERTY.OFFERS:
self.addOffering(Offering.parse(statement.getResource()))
return
# target
if predicate == PROPERTY.TARGET:
self.addTarget(statement.getString())
return
# label
if predicate == PROPERTY.RDFS_LABEL:
self.setName(statement.getString())
return
# comment
if predicate == PROPERTY.COMMENT:
self.setDescription(statement.getString())
return
# sessionKey
if predicate == PROPERTY.SESSIONKEY:
self.setSessionKey(statement.getString())
return
# signature
if predicate == PROPERTY.SIGNATURE:
self.setSignature(statement.getString())
return
# hashcode
if predicate == PROPERTY.HASHCODE:
self.setHashCode(statement.getString())
return
# encryptionKeyType
if predicate == PROPERTY.ENCRYPTIONKEYTYPE:
self.setEncryptionKeyType(statement.getResource().toString())
return
# notary
if predicate == PROPERTY.NOTARY:
self.setNotary(statement.getResource().toString())
return
# parameters
if predicate == PROPERTY.PARAMETER:
p = Parameter().parse(statement.getResource())
self.add(p.getKey(), p.getValues())
return
# if literal object
if isinstance(objectNode, Literal):
self.add(URIRef(predicate), objectNode.toPython())
#print 'DEBUG: ', objectNode.datatype, '...', objectNode
# if ((objectNode.datatype is not None) and objectNode.datatype == XSD.duration):
# self.add(URIRef(predicate), statement.getString())
# else:
# self.add(URIRef(predicate), objectNode.toPython())
return
# if isinstance(objectNode, URIRef):
# print "parse URI resource ", objectNode
# self.add(URIRef(predicate), objectNode)
# return
# if resource
if isinstance(objectNode, URIRef):
resource = statement.getResource()
# first check if resource has a type implemented built-in
# and parse using that
klass = Tools().getResourceClass(resource, default=Obj)
if klass is not None:
self.add(URIRef(predicate), klass.parse(resource))
else:
# None found, resort to Obj (the base class)
self.add(URIRef(predicate), Obj.parse(resource))
return
# Nothing else matches, use BNode as blank default entry
if isinstance(objectNode, BNode):
try:
klass = Tools().getResourceClass(statement.getResource(),
default=None)
except:
klass = None
if klass is not None:
self.add(URIRef(predicate),
klass.parse(statement.getResource()))
else:
self.add(URIRef(predicate), objectNode.toPython())
return
def parse(cls, element):
'''
factory method and class method. It takes in Resource as parameter, create a Seas Obj or
its subClass object.
@return: this newly created object, which could be either a real Obj or its subclass Object
or a Reference, whose actual content is in multipart message's body part
'''
if isinstance(element, Resource) and Tools.parsedObjs.has_key(
element.toString()):
return Tools.parsedObjs.get(element.toString())
elif isinstance(
element,
Resource) and not Tools.parsedObjs.has_key(element.toString()):
if not element.isAnon():
obj = cls(element.toString())
else:
obj = cls()
Tools.parsedObjs[element.toString()] = obj
for i in element.findProperties():
obj.parseStatement(i)
# check whether this Obj is a reference
if obj.isOfType(RESOURCE.MULTIPARTREFERENCE):
if obj.hasIdentifierUri():
if (len(Tools.messagePartsForParse) >
0) and (obj.getIdentifierUri()
in Tools.messagePartsForParse):
stringRepresentation = Tools.messagePartsForParse[
obj.getIdentifierUri()]
# if this Obj is EncryptedReference, it will be decrypted later by decrypt() call.
if obj.isOfType(RESOURCE.ENCRYPTEDREFERENCE):
obj.encryptedStringRepresentation = stringRepresentation
else: # if not encrypted, replace this reference Obj with a new Object,
# which is deserialzed from the stringRepresentation, containing actual content.
# This happens in the case of digital signature
model = Tools().fromString(stringRepresentation,
SERIALIZATION.TURTLE)
# find the root Resource
rootRes = Tools().getTopNode(model)[0]
# figure out its SMARTAPI Class
seasCls = Tools().getResourceClass(rootRes)
# recover it to Obj or its subclass Object
recoveredObj = seasCls.parse(rootRes)
# copy signature, hashcode from reference Obj to recovered Obj
recoveredObj.setSignature(obj.getSignature())
recoveredObj.setHashCode(obj.getHashCode())
recoveredObj.types.remove(
URIRef(RESOURCE.REFERENCE))
obj = recoveredObj
del Tools.messagePartsForParse[obj.getIdentifierUri()]
else:
raise Exception(
'******* ERROR: can not find the encrypted string representation of {}'
.format(obj.getIdentifierUri()))
#try:
# raise Exception('just to check!!!')
#except:
# traceback.print_stack()
else:
raise Exception(
'***** ERROR: reference Obj has to be named!!!*******')
return obj
return None
