Questions tagged [truffle]
Questions regarding the implementation and use of the Truffle development and testing environment.
2,031
questions
0
votes
1answer
32 views
Cannot create contract from another contract - truffle and ganache
I'm trying to write a test with ganache and truffle to create a contract instance from another contract.
Everything works in Remix but it doesn't in ganache. This is the code
const assert = require('...
0
votes
0answers
13 views
Truffle contract bytecode not updating with library address
After deploying a library using truffle, I want to compile a contract and use the library address inside its generated bytecode. Now inside the contract bytecode I get something like _DateTime______.
...
0
votes
0answers
17 views
ParserError: Expected token Semicolon got 'Return'
The error pops up whenever I try to compile through truffle, not able to figure out a solution any help is highly appreciated.
Here is the error
Compiling your contracts...
==========================...
0
votes
0answers
20 views
Migrating 2 contracts in one Contract.sol script using 'truffle migrate'
I have 2 contracts in 1 .sol file and when I run 'truffle migrate', it tells me that it has deployed 1 of the contracts and given me an additional error:
Blockquote
Invalid number of parameters ...
1
vote
0answers
7 views
What are the differences between Drizzle and the Truffle React box?
Truffle has many "boxes", two of which are:
truffle unbox react
And:
truffle unbox drizzle
They both seem to be focused on frontend development. Other than Drizzle being based on a Redux store, ...
0
votes
0answers
12 views
Automatically set app instance in Truffle console
Is there a way to load the truffle console with the following variables without having to do manual type-ins on every test?
let app = await MyContract.deployed();
let accounts = web3.eth.getAccounts()...
0
votes
1answer
20 views
Importing OpenZeppelin loads all node_modules contracts into Ganache
I install OpenZeppelin's contracts npm install @openzeppelin/contracts
Create a contract:
pragma solidity ^0.5.0;
import "@openzeppelin/contracts/token/ERC20/ERC20Mintable.sol";
contract NewCoin ...
0
votes
1answer
26 views
How to pass parameters into test script
I have a voting solidity file here:
pragma solidity >=0.4.21 <0.7.0;
// We have to specify what version of compiler this code will compile with
contract Votingapp{
/* mapping field below is ...
0
votes
0answers
12 views
Tuffle. New account from mnemonic during migrations
I'm trying to create a new account from predefined mnemonic during Truffle migrations(both testing and prod environments). I want to pre-create multiple contracts using corresponded factories for this ...
0
votes
0answers
20 views
XMLHttpRequest() does not work probably in a Truffle project
I want to connect to my smart contract in a Truffle project and get some information from it. The smart contract's name is "TEST". The follow is my app.js code that should communicate with my smart ...
0
votes
1answer
13 views
How of should I migrate my Smart Contract?
I am developing a scraper which scrapes data and puts it on ethereum blockchain(ganache for dev) every week. So as to put this data onto the blockchain should I migrate my smart contract each time I ...
0
votes
1answer
20 views
How do i see my records stored in the ethereum blockchain
So I have a smart contract, in my code, I have an array and i am pushing to it using a particular method call addToUser, from the code below
Contract Example{
string[] users;
function addToUser(_user) ...
0
votes
0answers
18 views
Using web3.js to interface with smart contract
I am a beginner in Dapp and don't know about web3.js. I complie myslef contracts with Truffle. I did write the following contract:
pragma solidity ^0.5.12;
contract TEST{
bytes public name="...
0
votes
1answer
14 views
How do you pass an array as an argument to a contract *constructor* using Truffle deployment script
I need to pass array as argument to contract constructor using truffle deployment script.
My contract code looks like this:
pragma solidity ^0.5.0;
contract ArrayArgument {
uint[] public arrsv;...
0
votes
1answer
17 views
How to use older version of Solidity in Truffle suite
I've tried to migrate contract on an older version of solidity, I have modified the config.js to be as in the following
and the smart contract solidity code I'm trying to deploy as follows
The ...
0
votes
1answer
20 views
How do I get all logs for all time for a given contract using web3?
This answer worked when filter.get was not deprecated, but now I am not sure how to do the same thing with subscribe - web3.eth.subscribe hears new events and acts on them after I create the ...
0
votes
1answer
19 views
Transfer ethers from a smart contract to another smart contract in Truffle
I am beginner in Solidity, So my problem maybe simple. I have two contracts "BankA" and "customer". Whenever i deploy BankA in Truffle network and call pay() the following Error will emerge:
Error: ...
1
vote
1answer
13 views
Is gas used during truffle tests on ganache the same as main net?
I am testing the amount of gas used for my contract functions using Truffle and Ganache CLI. Does anyone know if I can assume that the gas usage reported during my tests will be an accurate ...
0
votes
1answer
30 views
Unable to filter events with specific values of indexed parameters
I am currently trying to test a smart contract using the truffle suit ( with 'truffle test'). My contract is of a simple ERC20 token which includes the standard Transfer event:
event Transfer(address ...
1
vote
1answer
35 views
Ganache: out-of-gas during deployment
I have a bunch of contracts which deploy just fine.
Deployment of one of the contracts, XBRNetwork takes exactly 5418911 gas - no problems with that.
However, once I add another trivial (public) ...
1
vote
1answer
28 views
Difference between web3.eth.personal.getAccounts() with web3.eth.getAccounts()
What are the differences between web3.eth.personal.getAccounts() and web3.eth.getAccounts()?
environment
truffle: v5.1.7
using truffle console.
-2
votes
2answers
42 views
Can I make a proper website by using ganache and truffle? Like maybe abc.com?
I have developed a voting system usinh dapp that runs on local host. It uses accounts from ganache and metamask for transactions of votes. Now if i want to buy a domain and make the thing work, is it ...
0
votes
2answers
43 views
Measuring deployment time of a group of transactions in a heavy load testing
I am currently trying to perform heavy load testing on a ERC20 token. My plan is to use truffle to test stuff like how long it would take for 500 transfer transactions to be deployed (on a private ...
0
votes
1answer
29 views
Compilation failed during instrumentation of solidity-coverage
Getting compilation failed error, while running solidity-coverage.
Truffle compile is working fine
Here is my truffle config
networks: {
coverage: {
host: '127.0.0.1',
network_id: ...
0
votes
1answer
51 views
Calling function from existing truffle contract in node.js
This is probably a very simple problem to solve, but I am setting up a node.js backend using express for my Dapp and I can now deploy new contracts just fine.
I now need to figure out how to make ...
0
votes
1answer
11 views
Testing Smart Contract with multiple clients
After deploying a smart contract on Ropsten Testnet using Truffle framework, we can use truffle tests to do unit testing (create a client to interact with the deployed contract). My question is, how ...
0
votes
0answers
12 views
How to send a value back to html from node.js using express and truffle
I am running truffle code with Node.JS in the backend to deploy contracts. Using the Express Library, I can interact with the Node backend.
Here is the code for the HTML page:
<form id="myForm" ...
0
votes
1answer
17 views
Testing library functions with Javascript & Truffle
I'm trying to test functions of a library with Truffle. But they don't seem to be available.
The library is named Commons and I include it as I would include a contract:
var Commons = artifacts....
0
votes
1answer
51 views
Problem with running truffle code with node.js
I am trying to run truffle code with Node.JS in the backend to deploy contracts. I want to be able to do this interactively and I am intending to use the Express Library to interact with the Node ...
0
votes
1answer
45 views
Using the correct/best solc version with Truffle and general tooling setup
I haven't worked with Truffle/Solidity for a while and I am trying to get my environment/toolchain configure correctly. I have some questions regarding the compiler config.
I was originally not ...
1
vote
1answer
30 views
Logic help needed, how to transfer funds to the address who placed bets on winning team?
This is a betting application and
right now -> if I place bets on HOME, the amount gets stored but I want to transfer the amount only to the address who placed bets on winning team. I have developed ...
0
votes
1answer
47 views
How to Open console In geth 1.9.10
I am currently using geth in windows and 1.9.10LTS version of geth.
I have to Open geth console, but when i try to implement geth console or geth attach or geth attach ipc:\\ .\pipe\geth.ipc it doesn'...
0
votes
1answer
10 views
Truffle test: “Cannot read property 'gasUsed' of null” error. Truffle migrate works fine
Whenever I try and do truffle test I get the error
Cannot read property 'gasUsed' of null
But truffle migrate --reset works fine
More confusingly, to rule out something in one of my tests that is ...
0
votes
0answers
26 views
Not able to call the solidity function through App.js? Anyone know how to call a solidity function?
I'm trying to call a Solidity function from App.js, but I'm unsuccessful even after a number of tries.
Its a very simple function betOnTeam(). Inside this function I just want to check condition and ...
0
votes
1answer
21 views
How to call such a function? (pass argument)
For example, here is the code
What will the best code practice, either to repeat the code inside two different functions or what can I do?
OraclizeContract.deployed().then(function(instance) {
...
0
votes
1answer
39 views
Enabling truffle compile optimizer does not change the deployment gas cost
I am trying to deploy my contract by enabling the optimizer to see how much I can save from the gas costs.
I am using truffle for the deployment. In truffle I enable the optimizer by the following ...
0
votes
1answer
34 views
Function stopped working? No check is being done now on transfer function
I created a function to deposit and transfer ether and it was working great until i tried to deploy again and now
the transfer function is not working anymore
No errors are being thrown, the transfer ...
0
votes
2answers
39 views
Cannot transfer ether from smart contract to another address
I am using truffle and when we type
truffle develop it provides us with 10 address **
So, the problem I am facing is I have created 2 functions one to deposit ether and the other one to transfer the ...
0
votes
0answers
26 views
“truffle migrate --network ropsten” stuck after compiling
I am trying to redeploy a contract on Ropsten Testnet using the command:
truffle migrate --reset -f 1567182283 --network ropsten
Here, "1567182283" is the prefix of my migration file. Upon executing,...
0
votes
1answer
17 views
Redeploy contract on Ropsten Network
I have already deployed my smart contract on Ropsten network for testing using truffle suite. The command line I used was:
truffle deploy --network ropsten
Now, I have made some changes to my ...
0
votes
0answers
50 views
Cant call solidity function from app.js?
Solidity function Using web3 0.20 version and
Cant call solidity BETONTEAM function
pragma solidity ^0.4.22;
import "installed_contracts/strings.sol";
import "installed_contracts/oraclize-api/...
0
votes
0answers
29 views
Cant call solidity function from app.js while sending transaction
Solidity function
As i want to call function so that oraclize can send query
function betOnTeam(uint team) payable public {
update();
emit LogInfo("Oraclize query was NOT sent, ...
1
vote
1answer
27 views
Can someone explain the difference between using metamask or web3 to send ether from truffle accounts?
I am using web3 and truffle (i am a newbie wants to understand concept)
I need to transfer ether so i understand that i need to use
web3.eth.sendtransaction
But will it work as i am using localhost ...
0
votes
1answer
24 views
Can we take input of an address and pass it on the function to send ether using truffle and web3?
Actually i am trying to create a betting application so when i get the result that Home team has won Before this i will be taking both address as input (betting do two address whoever wins gets the ...
0
votes
1answer
37 views
How to encode an object with ABIEncoder V2?
How to encode an object with ABIEncoder V2?
For example, this one:
{
items: [
{
str: "str",
num: 5,
bol: true
}
]
}
Solidity struct:
struct Item {
string str;
...
0
votes
1answer
33 views
Getting stuck in truffle testing
I am trying to run a test and I am getting the following message;
I have tried the following;
npm install scrypt
npm install web3
as to solve the yellow message and when running truffle test
...
1
vote
2answers
27 views
How to read data returned by a function? [duplicate]
Counter.sol:
pragma solidity >=0.5.0 <0.7.0;
contract Counter {
uint public _counter = 0;
function GenNextID() public returns (uint) {
return _counter++;
}
}
I use ...
0
votes
2answers
35 views
Function, variable, struct or modifier declaration expected [duplicate]
I am using the following code structure;
pragma solidity ^0.5.0;
contract TtdmToken {
uint256 public totalSupply;
function TtdmToken () public {
totalSupply = 1000000;
}
}
...
0
votes
0answers
49 views
How to call solidity function from javascript file? Keep getting error deploying through truffle and webpack
Error -> TypeError: fetch.amount is not a function
[WDS] Disconnected!
Please explain or provide code on how to call solidity function
Trying to call from ready() function
console.log(contract.abi)...
1
vote
1answer
16 views
Setting sending account in Truffle test
I need to create contracts from various accounts in a Truffle JS Test. To do so, I set:
let accounts = await web3.eth.getAccounts();
MyContract.web3.from = accounts[9];
Before creating my contract ...
