maheshmurthy / ethereum_voting_dapp Goto Github PK

Description

Transactions on blockchain can be removed due to chain reorganization.
When the vote transaction is executed in a block, the DApp update the vote count in the UI.
However, if the chain reorganization happens and the transaction got removed from history, but the vote count is not reverted.

Reproduce Steps

One reproduce example is given below.

1. submit a vote by sending a transaction
2. mine a block and execute the transaction
3. at this time, the DApp has updated the vote count
4. chain reorganization happens, where the previous transaction is removed from history
5. the vote count is not reverted as transaction does.

Expected Behaviour

The transaction removed by chain reorganization should reflected to the UI, and the vote count should also be reverted.

any idea on how to deploy a contract with a constructor bytes32 array?

function transferTo(address account) {
    if (!account.call.value(this.balance)()) throw;
}

This function appears on line 125 in Voting.sol in chapter 3. I'm wondering why the function isn't simply: account.transfer(this.balance);?

PS C:\Users\Acer\newelection\ethereum_voting_dapp-master\chapter2\node_modules\webpack-dev-server> npm run webpack-dev-server

[email protected] webpack-dev-server C:\Users\Acer\newelection\ethereum_voting_dapp-master\chapter2\node_modules\webpack-dev-server
node examples/run-example.js

internal/modules/cjs/loader.js:983
throw err;
^

Error: Cannot find module 'C:\Users\Acer\newelection\ethereum_voting_dapp-master\chapter2\node_modules\webpack-dev-server\examples\run-example.js'
er.js:980:15)
at Function.Module._load (internal/modules/cjs/loader.js:862:27)
at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)
at internal/main/run_main_module.js:18:47 {
}
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] webpack-dev-server: node examples/run-example.js
npm ERR! Exit status 1
PS C:\Users\Acer\newelection\ethereum_voting_dapp-master\chapter2\node_modules\webpack-dev-server> npm run webpack-dev-server

[email protected] webpack-dev-server C:\Users\Acer\newelection\ethereum_voting_dapp-master\chapter2\node_modules\webpack-dev-server
node examples/run-example.js

internal/modules/cjs/loader.js:983
throw err;
^

Error: Cannot find module 'C:\Users\Acer\newelection\ethereum_voting_dapp-master\chapter2\node_modules\webpack-dev-server\examples\run-example.js'
at Function.Module._resolveFilename (internal/modules/cjs/loader.js:980:15)
at Function.Module._load (internal/modules/cjs/loader.js:862:27)
at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)
at internal/main/run_main_module.js:18:47 {
code: 'MODULE_NOT_FOUND',
requireStack: []
}
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] webpack-dev-server: node examples/run-example.js
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] webpack-dev-server script.
npm ERR! This is probably not a problem with npm. There is likely
additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\Acer\AppData\Roaming\npm-cache_logs\2020-04-25T21_56_53_268Z-debug.log

i am not able to run npm run dev getting the above error

I run the following command:

1. truffle console
2. hash = web3.sha3("message")
3. web3.personal.sign(hash, web3.eth.account[0])
   When I run the above commands I can not sign. It reported the following error "TypeError: Cannot read property '0' of undefined"
   I'm using your chapter 4

html file links to app.js with incorrect path. Does it have an incorrect path? Or maybe does it use third library which allows to access to this file without of specifying the path to it like Meteor?

Hello. I was trying to deploy the contract of the chapter3 and the console printed this error:

The contract code couldn't be stored, please check your gas amount.

I compared the file 2_deploy_contracts.js used in chapter3 with used in chapter2 and I noticed that was missing the gas value as shown below:

// the actual chapter3 2_deploy_contracts.js file
var Voting = artifacts.require("./Voting.sol");
module.exports = function(deployer) {
  deployer.deploy(Voting, 1000, web3.toWei('0.1', 'ether'), ['Rama', 'Nick', 'Jose']);
}; 

//what I did
var Voting = artifacts.require("./Voting.sol");
module.exports = function(deployer) {
  deployer.deploy(Voting, 1000, web3.toWei('0.1', 'ether'), ['Rama', 'Nick', 'Jose'],{gas: 6700000});
};

It worked fine when I did it.
I don't know if it is correct or if I did something wrong.

Thanks!

Hi, first of all thanks for the great tutorial.

I just came across one minor issue. throw in Voting.sol is deprecated.

Does it make sense to replace it with revert()?

Promise failed to return

deployedContract.deploy({
... data: bytecode,
... arguments: [listOfCandidates.map(name => web3.utils.asciiToHex(name))]
... }).send({
... from: 'ENTER 1 OF 10 ACCOUNT ADDRESSES like 0xfb3....',
... gas: 1500000,
... gasPrice: web3.utils.toWei('0.00003', 'ether')
... }).then((newContractInstance) => {
... deployedContract.options.address = newContractInstance.options.address
... console.log(newContractInstance.options.address)
... });

**
Uncaught:
Error: Provided address "ENTER 1 OF 10 ACCOUNT ADDRESSES like 0xfb3...." is invalid, the capitalization checksum test failed, or its an indrect IBAN address which can't be converted.
at Object.inputAddressFormatter (F:\ethereum_voting_dapp-master\ethereum_voting_dapp-master\chapter1\node_modules\web3-core-helpers\lib\formatters.js:398:11)
at Contract.getOrSetDefaultOptions [as _getOrSetDefaultOptions] (F:\ethereum_voting_dapp-master\ethereum_voting_dapp-master\chapter1\node_modules\web3-eth-contract\lib\index.js:304:66)
at Object._processExecuteArguments (F:\ethereum_voting_dapp-master\ethereum_voting_dapp-master\chapter1\node_modules\web3-eth-contract\lib\index.js:700:42)
at Object._executeMethod (F:\ethereum_voting_dapp-master\ethereum_voting_dapp-master\chapter1\node_modules\web3-eth-contract\lib\index.js:720:68)**

Showing ERROR:: Uncaught (in promise) Error: invalid address

On running command truffle console or truffle migrate, the following error is thrown everytime even accounts exist.

/usr/local/lib/node_modules/truffle/lib/environment.js:66
        config.networks[config.network].from = accounts[0];
                                                       ^

TypeError: Cannot read property '0' of null
    at /usr/local/lib/node_modules/truffle/lib/environment.js:66:56
    at /usr/local/lib/node_modules/truffle/node_modules/web3/lib/web3/property.js:119:13
    at /usr/local/lib/node_modules/truffle/node_modules/web3/lib/web3/requestmanager.js:89:9
    at XMLHttpRequest.request.onreadystatechange (/usr/local/lib/node_modules/truffle/node_modules/web3/lib/web3/httpprovider.js:119:13)
    at XMLHttpRequestEventTarget.dispatchEvent (/usr/local/lib/node_modules/truffle/node_modules/xhr2/lib/xhr2.js:64:18)
    at XMLHttpRequest._setReadyState (/usr/local/lib/node_modules/truffle/node_modules/xhr2/lib/xhr2.js:354:12)
    at XMLHttpRequest._onHttpResponseEnd (/usr/local/lib/node_modules/truffle/node_modules/xhr2/lib/xhr2.js:509:12)
    at IncomingMessage.<anonymous> (/usr/local/lib/node_modules/truffle/node_modules/xhr2/lib/xhr2.js:469:24)
    at emitNone (events.js:91:20)
    at IncomingMessage.emit (events.js:185:7)
    at endReadableNT (_stream_readable.js:974:12)
    at _combinedTickCallback (internal/process/next_tick.js:74:11)
    at process._tickDomainCallback (internal/process/next_tick.js:122:9)

Getting this error on deplying the chapter 3 application using truffle 3 ..
Please help!!

Getting the following output on complining the code with :-
compiledCode = solc.compile(code)

Output:-
'{"errors":[{"component":"general","formattedMessage":"* Line 1, Column 1\\n Syntax error: value, object or array expected.\\n* Line 1, Column 2\\n Extra non-whitespace after JSON value.\\n","message":"* Line 1, Column 1\\n Syntax error: value, object or array expected.\\n* Line 1, Column 2\\n Extra non-whitespace after JSON value.\\n","severity":"error","type":"JSONError"}]}'

it seems like it keep returning zero

var buyObject = {
value: 25,
from: web3.eth.accounts[0]
};
contractInstance.buy.call(buyObject).then(function(result) {
console.log(">>>> " + result);
web3.eth.getBalance(contractInstance.address, function(error, result) {
console.log(result);
console.log(web3.fromWei(result.toString()));
});
}).catch(function(err) {
console.log("Error creating contract!" + err);
console.log(err.stack);
});

Account 0 : 99.99999999999662
Account 1 : 100
Account 2 : 99.99999999999846

pragma solidity ^0.4.6; //We have to specify what version of the compiler this code will use
Line 1 of Voting.sol should probably read:
pragma solidity ^0.4.10; //We have to specify what version of the compiler this code will use
Given the change to:
account.transfer(this.balance);
on line 126 the contract will no longer compile on solc version <0.4.10.
This gives the error:

Compiling ./contracts/Voting.sol...

/home/vagrant/ethereum_voting_dapp/chapter3/contracts/Voting.sol:126:5: Error: Member "transfer" not found or not visible after argument-dependent lookup in address
account.transfer(this.balance);
^--------------^
Compiliation failed. See above.

On previous solc versions.
I'd do a pull request but I'm having trouble installing the latest Truffle at the moment so can't verify the fix.