from rest_framework import status, serializers from rest_framework.generics import CreateAPIView, ListAPIView from rest_framework.views import APIView from rest_framework import viewsets from rest_framework.response import Response from django.contrib.auth import authenticate, login, logout from django.contrib.auth.models import User from .serializers import ListOrderSerializer, MakeOrderSerializer, UpdateInvoiceSerializer from .models import Order, LNPayment, Logics from .lightning import LNNode from .nick_generator.nick_generator import NickGenerator from robohash import Robohash from scipy.stats import entropy from math import log2 import numpy as np import hashlib from pathlib import Path from datetime import timedelta from django.utils import timezone # .env EXPIRATION_MAKE = 5 # minutes avatar_path = Path('frontend/static/assets/avatars') avatar_path.mkdir(parents=True, exist_ok=True) # Create your views here. class OrderMakerView(CreateAPIView): serializer_class = MakeOrderSerializer def post(self,request): serializer = self.serializer_class(data=request.data) if serializer.is_valid(): otype = serializer.data.get('type') currency = serializer.data.get('currency') amount = serializer.data.get('amount') payment_method = serializer.data.get('payment_method') premium = serializer.data.get('premium') satoshis = serializer.data.get('satoshis') is_explicit = serializer.data.get('is_explicit') valid, context = Logics.validate_already_maker_or_taker(request.user) if not valid: return Response(context, status=status.HTTP_409_CONFLICT) # Creates a new order in db order = Order( type=otype, status=Order.Status.WFB, currency=currency, amount=amount, payment_method=payment_method, premium=premium, satoshis=satoshis, is_explicit=is_explicit, expires_at=timezone.now()+timedelta(minutes=EXPIRATION_MAKE), maker=request.user) order.t0_satoshis=Logics.satoshis_now(order) # TODO reate Order class method when new instance is created! order.last_satoshis=Logics.satoshis_now(order) order.save() if not serializer.is_valid(): return Response(status=status.HTTP_400_BAD_REQUEST) return Response(ListOrderSerializer(order).data, status=status.HTTP_201_CREATED) class OrderView(viewsets.ViewSet): serializer_class = UpdateInvoiceSerializer lookup_url_kwarg = 'order_id' def get(self, request, format=None): order_id = request.GET.get(self.lookup_url_kwarg) if order_id == None: return Response({'Bad Request':'Order ID parameter not found in request'}, status=status.HTTP_400_BAD_REQUEST) order = Order.objects.filter(id=order_id) # check if exactly one order is found in the db if len(order) == 1 : order = order[0] # If order expired if order.status == Order.Status.EXP: return Response({'bad_request':'This order has expired'},status.HTTP_400_BAD_REQUEST) data = ListOrderSerializer(order).data # Add booleans if user is maker, taker, partipant, buyer or seller data['is_maker'] = order.maker == request.user data['is_taker'] = order.taker == request.user data['is_participant'] = data['is_maker'] or data['is_taker'] # If not a participant and order is not public, forbid. if not data['is_participant'] and order.status != Order.Status.PUB: return Response({'bad_request':'Not allowed to see this order'},status.HTTP_403_FORBIDDEN) # non participants can view some details, but only if PUB elif not data['is_participant'] and order.status != Order.Status.PUB: return Response(data, status=status.HTTP_200_OK) # For participants add position side, nicks and status as message data['is_buyer'] = Logics.is_buyer(order,request.user) data['is_seller'] = Logics.is_seller(order,request.user) data['maker_nick'] = str(order.maker) data['taker_nick'] = str(order.taker) data['status_message'] = Order.Status(order.status).label # If status is 'waiting for maker bond', reply with a hodl invoice too. if order.status == Order.Status.WFB and data['is_maker']: valid, context = Logics.gen_maker_hodl_invoice(order, request.user) if valid: data = {**data, **context} else: Response(context, status=status.HTTP_400_BAD_REQUEST) return Response(data, status=status.HTTP_200_OK) return Response({'Order Not Found':'Invalid Order Id'},status=status.HTTP_404_NOT_FOUND) def take_or_update(self, request, format=None): order_id = request.GET.get(self.lookup_url_kwarg) serializer = UpdateInvoiceSerializer(data=request.data) order = Order.objects.get(id=order_id) if serializer.is_valid(): invoice = serializer.data.get('invoice') # If this is an empty POST request (no invoice), it must be taker request! if not invoice and order.status == Order.Status.PUB: valid, context = Logics.validate_already_maker_or_taker(request.user) if not valid: return Response(context, status=status.HTTP_409_CONFLICT) Logics.take(order, request.user) # An invoice came in! update it elif invoice: print(invoice) updated = Logics.update_invoice(order=order,user=request.user,invoice=invoice) if not updated: return Response({'bad_request':'Invalid Lightning Network Invoice. It starts by LNTB...'}) # Something else is going on. Probably not allowed. else: return Response({'bad_request':'Not allowed'}) return self.get(request) class UserView(APIView): lookup_url_kwarg = 'token' NickGen = NickGenerator( lang='English', use_adv=False, use_adj=True, use_noun=True, max_num=999) # Probably should be turned into a post method def get(self,request, format=None): ''' Get a new user derived from a high entropy token - Request has a high-entropy token, - Generates new nickname and avatar. - Creates login credentials (new User object) Response with Avatar and Nickname. ''' token = request.GET.get(self.lookup_url_kwarg) # Compute token entropy value, counts = np.unique(list(token), return_counts=True) shannon_entropy = entropy(counts, base=62) bits_entropy = log2(len(value)**len(token)) # Payload context = {'token_shannon_entropy': shannon_entropy, 'token_bits_entropy': bits_entropy} # Deny user gen if entropy below 128 bits or 0.7 shannon heterogeneity if bits_entropy < 128 or shannon_entropy < 0.7: context['bad_request'] = 'The token does not have enough entropy' return Response(context, status=status.HTTP_400_BAD_REQUEST) # Hashes the token, only 1 iteration. Maybe more is better. hash = hashlib.sha256(str.encode(token)).hexdigest() # Generate nickname nickname = self.NickGen.short_from_SHA256(hash, max_length=18)[0] context['nickname'] = nickname # Generate avatar rh = Robohash(hash) rh.assemble(roboset='set1', bgset='any')# for backgrounds ON # Does not replace image if existing (avoid re-avatar in case of nick collusion) image_path = avatar_path.joinpath(nickname+".png") if not image_path.exists(): with open(image_path, "wb") as f: rh.img.save(f, format="png") # Create new credentials and logsin if nickname is new if len(User.objects.filter(username=nickname)) == 0: User.objects.create_user(username=nickname, password=token, is_staff=False) user = authenticate(request, username=nickname, password=token) user.profile.avatar = str(image_path)[9:] # removes frontend/ from url (ugly, to be fixed) login(request, user) return Response(context, status=status.HTTP_201_CREATED) else: user = authenticate(request, username=nickname, password=token) if user is not None: login(request, user) # Sends the welcome back message, only if created +30 mins ago if request.user.date_joined < (timezone.now()-timedelta(minutes=30)): context['found'] = 'We found your Robosat. Welcome back!' return Response(context, status=status.HTTP_202_ACCEPTED) else: # It is unlikely, but maybe the nickname is taken (1 in 20 Billion change) context['found'] = 'Bad luck, this nickname is taken' context['bad_request'] = 'Enter a different token' return Response(context, status=status.HTTP_403_FORBIDDEN) def delete(self,request): user = User.objects.get(id = request.user.id) # TO DO. Pressing "give me another" deletes the logged in user # However it might be a long time recovered user # Only delete if user live is < 5 minutes # TODO check if user exists AND it is not a maker or taker! if user is not None: logout(request) user.delete() return Response({'user_deleted':'User deleted permanently'},status=status.HTTP_302_FOUND) return Response(status=status.HTTP_403_FORBIDDEN) class BookView(ListAPIView): serializer_class = ListOrderSerializer def get(self,request, format=None): currency = request.GET.get('currency') type = request.GET.get('type') queryset = Order.objects.filter(currency=currency, type=type, status=int(Order.Status.PUB)) if len(queryset)== 0: return Response({'not_found':'No orders found, be the first to make one'}, status=status.HTTP_404_NOT_FOUND) queryset = queryset.order_by('created_at') book_data = [] for order in queryset: data = ListOrderSerializer(order).data user = User.objects.filter(id=data['maker']) if len(user) == 1: data['maker_nick'] = user[0].username # Non participants should not see the status or who is the taker for key in ('status','taker'): del data[key] book_data.append(data) return Response(book_data, status=status.HTTP_200_OK)