receptionist_server.py

from flask import Flask, jsonify, request, render_template
from web3 import Web3, IPCProvider, Account
from web3.middleware import geth_poa_middleware
import pickle

# abi is changin when you change contract
ABI =  [{'constant': False, 'inputs': [{'name': 'data', 'type': 'string'}], 'name': 'enqueue', 'outputs': [], 'payable': False, 'stateMutability': 'nonpayable', 'type': 'function'}, {'constant': False, 'inputs': [], 'name': 'lenght', 'outputs': [{'name': '', 'type': 'uint256'}], 'payable': False, 'stateMutability': 'nonpayable', 'type': 'function'}, {'constant': False, 'inputs': [{'name': 'position', 'type': 'uint256'}], 'name': 'get_patient', 'outputs': [{'name': '', 'type': 'string'}], 'payable': False, 'stateMutability': 'nonpayable', 'type': 'function'}, {'constant': True, 'inputs': [{'name': '', 'type': 'uint256'}], 'name': 'receptionistAccts', 'outputs': [{'name': '', 'type': 'address'}], 'payable': False, 'stateMutability': 'view', 'type': 'function'}, {'constant': False, 'inputs': [], 'name': 'dequeue', 'outputs': [{'name': 'data', 'type': 'string'}], 'payable': False, 'stateMutability': 'nonpayable', 'type': 'function'}, {'constant': False, 'inputs': [], 'name': 'greet', 'outputs': [{'name': 'greet', 'type': 'string'}], 'payable': False, 'stateMutability': 'nonpayable', 'type': 'function'}]

with open ('ABI.txt', 'rb') as fp:
    ABI = pickle.load(fp)

# addres change when you deploy contract (if you not reset blockchain, old contract exists)
ADDRESS = '0xcc2b57418d1CA582D757d6F9b39Dd53817FA70B7'

with open('address.txt','r') as f:
    ADDRESS = f.read()
print("Address: ", ADDRESS)

app = Flask(__name__, template_folder='./templates')

def greeting():
    print('Default contract greeting: {}'.format(
        queue.functions.greet().call()
    ))

def connect_to_blockchain():
    w3 = Web3(IPCProvider(ipc_path='/tmp/geth.ipc', testnet=True))
    w3.middleware_stack.inject(geth_poa_middleware, layer=0)
    queue = w3.eth.contract(address=ADDRESS, abi=ABI)

    return w3, queue

def add_patient_to_queue(patient):
    # w3.personal.unlockAccount('0x8E91F458978FFD2BBD77709ce9726fC1e9eA7a62', 'pass')
    tx_hash = queue.functions.enqueue(patient).transact()
    # Wait for transaction to be mined...
    w3.eth.waitForTransactionReceipt(tx_hash)


def read_all_patient():
    patients = []
    lenght = queue.functions.lenght().call()
    last = queue.functions.end().call()
    first = queue.functions.start().call()
    print(lenght)

    #for i in range(lenght - last + 1,lenght+1):
    for i in range(first+1,last+1):
        patients.append(queue.functions.get_patient(i).call())

    return patients

def remove_first_patient():
    tx_hash = queue.functions.dequeue().transact()
    # Wait for transaction to be mined...
    removed_patient = w3.eth.waitForTransactionReceipt(tx_hash)
    print(removed_patient)

@app.route('/')
def index():
    return render_template('index.html', node_identifier=1, node_money=1), 200

@app.route('/list_patients', methods=['GET'])
def list_patients():
    return render_template('list_patients.html', patients=read_all_patient()), 200

@app.route('/add_patient', methods=['GET'])
def add_patient_form():
    return render_template('add_patient.html'), 200

@app.route('/add_patient', methods=['POST'])
def add_patient():
    values = request.form

    # Check that the required fields are in the POST'ed data
    required = ['patient_name']
    if not all(k in values for k in required):
        return 'Missing values', 400

    patient_name = values['patient_name']

    # w3.personal.unlockAccount(w3.personal.listAccounts[0], "", 15000)
    add_patient_to_queue(patient_name)

    return render_template('index.html', response='OK'), 201

@app.route('/remove_first_patient', methods=['POST'])
def remove_first_patient_form():
    remove_first_patient()
    return render_template('list_patients.html', patients=read_all_patient()), 201

w3, queue = connect_to_blockchain()
# print(w3.eth.accounts[0])
w3.eth.defaultAccount = w3.eth.accounts[0]
greeting()

app.run(host='0.0.0.0', port=5000)