app.py

import streamlit as st
import requests
import json
import web3

abi = [{"anonymous":False,"inputs":[{"indexed":False,"internalType":"string","name":"ipfsHash","type":"string"}],"name":"Store","type":"event"},{"inputs":[],"name":"getHashes","outputs":[{"internalType":"string[]","name":"","type":"string[]"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"string","name":"ipfsHash","type":"string"}],"name":"storeHash","outputs":[],"stateMutability":"nonpayable","type":"function"}]
# function that uploads the results to ipfs
def upload_json_to_ipfs(data):
    try:
        url = "https://api.pinata.cloud/pinning/pinJSONToIPFS"

        print("starting upload to ipfs")

        # check for JWT secret
        if "PinataJWT" not in st.secrets:
            st.write("No JWT secret found, please add your JWT in a secret titled \"PinataJWT\"")
            return

        jwt_token = st.secrets["PinataJWT"].strip()
        headers = {
            "Authorization": f"Bearer {jwt_token}",
            "Content-Type": "application/json"
        }

        # Convert Python dictionary to JSON string
        response = requests.post(url, headers=headers, json=data)

        if response.status_code == 200:
            # Print the IPFS hash from the successful response
            ipfs_hash = response.json().get("IpfsHash")
            return ipfs_hash
        else:
            st.write(f"Failed to upload JSON. Status code: {response.status_code}")
            st.write(response.text)
            return None
    except Exception as e:
        st.write(f"Error uploading to Pinata: {e}")

# function that uploads to blockchain
def upload_to_blockchain(hash):
    print("starting blockchain upload")
    w3 = web3.Web3(web3.HTTPProvider(st.secrets["infura"]))

    # create an instance of our contract
    contract = w3.eth.contract(address=st.secrets["ContractAddress"], abi = abi)

    # Call your function: 11155111 is Sepolia's id
    call_function = contract.functions.storeHash(hash).build_transaction({"chainId": 11155111, 
                                                                            "from": st.secrets["EthWallet"],
                                                                            "nonce": w3.eth.get_transaction_count(st.secrets["EthWallet"])})

    # Sign transaction
    signed_tx = w3.eth.account.sign_transaction(call_function, private_key=st.secrets["pk"])

    # Send transaction
    send_tx = w3.eth.send_raw_transaction(signed_tx.raw_transaction)

    # Wait for transaction receipt
    tx_receipt = w3.eth.wait_for_transaction_receipt(send_tx)

    print("ETH Hash:")
    print(tx_receipt.logs[0].transactionHash.hex())

    return tx_receipt.logs[0].transactionHash.hex()

def get_ipfs_hashes():
    w3 = web3.Web3(web3.HTTPProvider(st.secrets["infura"]))

    # Create an instance of the contract
    contract = w3.eth.contract(address=st.secrets["ContractAddress"], abi=abi)

    # Call the getHashes function
    try:
        ipfs_hashes = contract.functions.getHashes().call()
        return ipfs_hashes
    except Exception as e:
        st.write(f"Error retrieving hashes: {e}")
        return []
    
def retreive_ipfs_hash_data(hashes):
    results = []
    for ipfs_hash in hashes:
        url = f"https://gateway.pinata.cloud/ipfs/{ipfs_hash}"
        try:
            response = requests.get(url)
            if response.status_code == 200:
                data = response.json()
                results.append({"hash": ipfs_hash, "data": data})
            else:
                results.append({"hash": ipfs_hash, "error": f"Failed to retrieve data (status {response.status_code})"})
        except Exception as e:
            results.append({"hash": ipfs_hash, "error": str(e)})
    return results


# function that handles survey submission
# sets up ipfs and blockchain
def submission(survey_data):
    ipfs_hash = upload_json_to_ipfs(survey_data)
    if ipfs_hash:
        print("IPFS Upload Successful")
        print(ipfs_hash)
        upload_to_blockchain(ipfs_hash)
total_number_pages = 2
placeholder_buttons = None

Q1_radio_options = ["Yippee","Oh No"]


# Function that records radio element changes
def radio_change(element, state, key):
   st.session_state[state] = element.index(st.session_state[key]) # Setting previously selected option

def multi_change(element, state, key):
   st.session_state[state] = []
   for selected_option in st.session_state[key]:
       st.session_state[state].append(selected_option)

# Function that disables the last button while data is uploaded to IPFS
def button_disable():
   st.session_state['disabled'] = True

def answer_change(state, key):
   st.session_state[state] = st.session_state[key]

st.set_page_config(page_title='IPFS-Based Survey',)
st.title('')

st.markdown("<style>.row-widget.stButton {text-align: center;}</style>", unsafe_allow_html=True)
st.markdown("<style>.big-font {font-size:24px;}</style>", unsafe_allow_html=True)


if "current_page" not in st.session_state:
    st.session_state["current_page"] = 1
    st.session_state["Q1"] = None
    st.session_state["disabled"] = False

# Page 1; Video
if st.session_state["current_page"]  == 1:

    st.markdown("""<p class="big-font"></p>""", unsafe_allow_html=True)

    st.radio(label     = "Test Survey Question", 
             options   = Q1_radio_options, 
             index     = None if st.session_state["Q1"] == None else st.session_state["Q1"], 
             key       = 'Q1_radio', 
             on_change = radio_change, 
             args      = (Q1_radio_options, "Q1", "Q1_radio",))

    st.markdown("""<style> div[class*="stRadio"] > label > div[data-testid="stMarkdownContainer"] > p {font-size: 18px;}</style> <br><br>""", unsafe_allow_html=True)


    placeholder = st.empty()

    if st.button('Next'):
        all_answered = True
        if st.session_state["Q1"] == None or st.session_state["Q1"] == []:
            all_answered = False
        if all_answered:
            st.session_state["current_page"] += 1
            st.rerun()
        else:
            with placeholder.container():
                st.warning("Please answer all the questions on this page.", icon="⚠️")

    st.progress(st.session_state["current_page"]/total_number_pages, text="Progress")


elif st.session_state["current_page"] == 2: # Last Page
    st.markdown('<p class="big-font">Thank you for participating! <br> Click on the button below to submit your answers. </p>', unsafe_allow_html=True)
    st.button('Submit Responses', disabled = st.session_state["disabled"], on_click = button_disable)
    if st.session_state["disabled"]:
        with st.spinner(r"$\textsf{\normalsize Storing data on IPFS and Ethereum. This operation might take a few minutes. Please wait to receive your confirmation code!}$"):
            try:
                response = {
                    "Q1": Q1_radio_options[st.session_state["Q1"]],
                }
                submission(response)
            except Exception as e:
                print(e)
                st.error(f'An error ocurred. Here is the error message: {e}', icon="🚨")

    if st.button('Back'):
        st.session_state["current_page"] -= 1
        st.rerun()
    st.progress(st.session_state["current_page"]/total_number_pages, text="Progress")