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3
votes
1answer
664 views

Ropsten infura test network + web3 js event listener

I have deployed contracts on ropsten test network. truffle.js ropsten: { provider: function() { return new HDWalletProvider(mnemonic, "https://ropsten.infura.io/<api-token>") }, ...
0
votes
0answers
3 views

Watching for events

How come sometimes events show up on block explorers in hex and sometimes to you can see the actual string name of the event in the logs. I ask because my event watchers on my front end only pick up ...
0
votes
1answer
451 views

Setting up MyEtherWallet on iOS device from Coinbase

Can I securely set up and store a MyEthereumWallet on iOS only without an computer? I want to transfer ethers from Coinbase.
2
votes
1answer
25 views

How to change the crypto-currency that is used in paying for gas fees in a private network

I have deployed my own network of blockchain that is based on the ethereum network. I wanted to know if one could change the currency used to pay for the gas on the private network.
0
votes
2answers
14 views

Connect dApp hosted on cloud with Geth running locally

I've my dApp running on AWS and Geth running locally. How am I supposed to connect my hosted dApp with the Geth? I'm connecting my web3(using web3.py) using my computer's(Windows OS) IP address. ...
1
vote
1answer
13 views

Cannot verify Solidity contract code on etherscan.io

I am unable to verify the contract below on Etherscan. No errors in Remix. I tried all of the solutions recommended in answers to similar questions, which were: Remove the ^ in pragma Compile ...
0
votes
1answer
206 views

Replacing a requirement for TRC10 token with TRC20 on a TRX contract

I have a contract that allows users to buy a token and pay with a TRC10 token deployed on Tron. Is it possible to replace the token ID with a TRC20 address instead? And if so, how do I implement it? ...
1
vote
1answer
21 views

Ethereum Contract Simplify

I'm confused about 'contracts' in Ethereum. When do I need a 'contract'? For the scope of my app: I want user to be able to generate ETH address, receive and send out ETHER and I should be able to ...
0
votes
1answer
415 views

Mist Wallet Stuck on “Connected to Node”

It got about 80% of the way through the blockchain download, then it just stopped and went to "finding peers" So I closed the wallet, restarted the PC, and now it just gets stuck on "connected to node"...
0
votes
0answers
10 views

Delegate transaction signature

What's the most efficient and trust-less way to sign a transaction through a middle-ware? Thanks for your help.
1
vote
1answer
32 views

What is the advantage and disadvantage of deploying Erays on Ethereum?

I have read this paper, Erays: Reverse Engineering Ethereum's Opaque Smart Contracts. They proposed this reverse engineering tool for Ethereum smart contracts. it will take as input a compiled EVM ...
-1
votes
0answers
6 views

autocall send recieve tokens (what is best way )

my need : autocall for m-reson happen in my contract to send ETH to m_address of binance sell it there and then send back usdt to contract is there a way to do this in decentrlized way ? ...
0
votes
1answer
40 views

Implementing 2 phase commit (2pc) with solidity

Are there some patterns or some way to implement 2 phase commit with solidity? Something similar to multi signatures and a fail safe mechanism.
2
votes
0answers
11 views

How to calculate vanity address using C?

I have a curiosity about tacking on zeroes to strings, and Ethereum addresses are no exception. I wrote my own python program, and it was too slow. I wrote the program at https://pastebin.com/hTFGiKzR ...
-1
votes
1answer
31 views

Using await with web3 function calls

I have just implemented a tweak to make my asynchronous call run sequentially, however it is messy solution. I have got the following code: async function myClick() { calculateAmounts(); ...
1
vote
1answer
3k views

Create multiple addresses under main wallet address

As in exchanges, They provide their users only deposit address but not private keys and our all funds exists under main exchange account. How is it possible to setup ethereum in our own server? ...
1
vote
2answers
277 views

can't access web3 object in Drizzle Box

I am building a DAPP based on drizzle box. I am struggling to find out how can i get the web3 instance without initiating a new one I want to end up with something like : this.props.web3.eth Thanks
3
votes
2answers
587 views

How can I access the address of a contract in a drizzle dapp?

I've started working from the drizzle box and can access functions within contracts, but if I want to give an allowance to a contract address so it can use users tokens how can I give the correct ...
0
votes
2answers
33 views

How DApp actually talks to Ganache ethereum node?

Both Metamask and web3.js seems to be enabling a DApp communicates to a remote ethereum node. There are a few different aspects to developing blockchain applications with Ethereum: Smart ...
2
votes
3answers
132 views

Is drizzle a contracts lib?

I'm researching about smart contracts, and been seeing a lot of truffleframework, ganache and drizzle. In the other hand, only found broad descriptions of those tools: "Drizzle is a collection of ...
1
vote
1answer
701 views

Why do I get VM Exception while processing transaction: revert?

I'm trying to call a function from a contract I've created on ganache-cli through a javascript on a website. Here's the code of the java script: web3.eth.defaultAccount=web3.eth.accounts[0]; var poe ...
0
votes
1answer
14 views

Dispute in smart contartcs

i don't have enough knowladge of contracts. any one have a good article about What is arbitration and dispute in smart contracts.can you please help.
1
vote
0answers
16 views

Address to create a contract

This query is for informational purposes, with something that has had me in doubt all night. I am trying to send a self-signed transaction for the creation of a contract My Tx transaction to send is ...
0
votes
1answer
93 views

Decoding Hex value in solidity

I am trying to view values stored on my ethereum contract using ethereum wallet. Currently the values are being placed onto the contract in hex format. Is there a way to decode them on the contract so ...
0
votes
2answers
31 views

multisend ERC20 tokens

I have main address: const fromAddress There is also an array of addresses and their keys:foreth/keys I need to send all erc20 tokens from: foreth array to the: fromAddress Tokens are sent only ...
0
votes
2answers
66 views

How to make token for exchange such as bittrex? I'm interested only in technical side of this question

Should I set a starting price for the token? Is there a source code for the token for trading on the exchange?
8
votes
2answers
656 views

How to create a secure, production ready private chain?

I'm looking for more information or resources on how to run a private chain with ethereum with multiple nodes that would work in production and would only be accessible to my users/network. I know ...
0
votes
2answers
22 views

How to get new transactions by addresses?

I have an array of addresses on my server which I need to track. What method should I use to do that via websockets? I’m new to eth and cryptocurrency at all, and I don’t understand “blocks”, “gas ...
0
votes
2answers
83 views

How to code ADDRESS using opcodes in a solidity function?

Reference - http://solidity.readthedocs.io/en/develop/assembly.html Objective - example of a function returning the contract address. Code - pragma solidity ^0.4.18; contract d4{ function ...
0
votes
0answers
19 views

How can execute function that send ether in geth console?

I want to execute the send function that sends ether from the sender to the receiver, the code is as shown below. contract Sender { function send(address _receiver , uint amount) public ...
0
votes
0answers
3 views

input field is not getting displayed by using ContractForm

<DrizzleProvider options={drizzleOptions}> <LoadingContainer> <div> <h1>Welcome Doctor</h1> ...
0
votes
1answer
294 views

Error: The data field must be HEX encoded data

I am trying to make a simple dApp by using a tutorial. I am using the following command ; npm install ganache-cli web3 so that we can use web3 to get fake ethereum nodes/accounts by connecting it ...
0
votes
1answer
240 views

Ethereum mist wallet not synchronising, not showing Ethereum and folder

I am a beginner at setting this up and I used a youtube tutorial to download Mist. The problem is it's not syncing the blockchains. I've tried to debug this by going to users/appdata and inside the ...
0
votes
1answer
12 views

how to call a function with ether through web3

I'm writing a simple DApp in webpack sample(metacoin) in truffle,there is a function that need to call with 2 ether and 1 input parameter. And my question is how to call that function in the index.js,...
0
votes
1answer
17 views

Send transaction with locked contract -> Error: insufficient funds for gas * price + value

I'm trying to send a transaction for a token with a locked contract. I'm doing this to find out when this contract will be open. So I'm expecting to get some kind of error like "ERC-20 Token Transfer ...
0
votes
1answer
38 views

Why my tokens aren't visible to the address sent in etherscan?

I've flattened the code and fixed the warning. But the problem with the contract is that the tokens are not visible in the addresses when searched with etherscan but when I try to add through Metamask,...
1
vote
1answer
11 views

how to create Function Selector (Method IDs)

As stated in ABI specs that 0xcdcd77c0: the Method ID. This is derived as the first 4 bytes of the Keccak hash of the ASCII form of the signature baz(uint32,bool). So, I have to create method IDs (...
0
votes
0answers
9 views

Some of the new Ethereum Txn hashes are not showing on any blockchain explorer

I have my own node setup using parity for ethereum. Everything was going perfect. But from today , means right after Ethereum hard forked into their improved version of "Istanbul" at block 9069000 ...
4
votes
3answers
269 views

Inability to verify contract with ABIEncoderV2 on Etherscan

Yesterday I deployed a contract to Ropsten (https://ropsten.etherscan.io/address/0x1fe59c223fa4e9781237f0f49a15ca598069cc30) that relies on V2 of the ABI encoder. Thus it includes statement pragma ...
0
votes
4answers
140 views

Gas estimation failed - remix

I am trying to figure out what is wrong with the following code as it does deploy successfully on remix. pragma solidity ^0.5.11; contract MyContract { // Storage address contractOwner; ...
1
vote
3answers
294 views

How can I call a function in deployed contract on Ropsten Testnet when I don't have ABI and source code?

For some testing I deployed several contracts on Ropsten Testnet using web3.py but now if I want to execute them or call any function from them, how can I do this? I don't have ABI as I did several ...
2
votes
1answer
49 views

Ethereum Private network for Production use case

When I should consider to use Ethereum Private network for Production use case? Can I dictate network difficulty rules and apply permission on such network. Regards Dev
0
votes
1answer
54 views

Solidity not updating value from delegate contract [SOLVED]

Assuming this contract: contract getSome { finalizeToken token; constructor() { token = finalizeToken(0xdc0974e65e479fa587118eb7588f426229a39d31); } function testWrite() ...
0
votes
0answers
19 views

Is it possible that a contract address is same as a external address?

For example i create a contract first, and then i generate a private key that map to the contract address. I know that is hard to achieve but is it possible theoretically?
0
votes
1answer
24 views

Can I record the Time taken for a transaction to complete in Test Net

I am trying to benchmark the time taken for a transaction to execute, can anybody advise me is there anyway I can record the time taken for smart contract transaction to complete?
0
votes
1answer
66 views

Transaction successful but ether not transferred to destination account

I am following this article and everything works expected but ether is not getting transferred to the to account.Please find the logs below. eth.sendTransaction({from:eth.accounts[0], to:eth.accounts[...
0
votes
1answer
29 views

Conflict in smart contracts

How is conflict handled in the case of smart contracts .For eg -in the case of an insurance smart contracts,there might be conflit between both parties.How does blockchain ensure the validity of ...
0
votes
1answer
34 views

Can we remove queued transaction in geth pool (PoA)?

Is there a way to limit time of queued transaction or remove them ? I am using PoA network (Geth)
3
votes
1answer
29 views

Merkle Hash forest and MErkle DAG is it the same?

I'm wondering if a merkle hash forest is the same as a merkle dag? I need a reliable paper as reference I could cite in my paper. Thx for all your help!
18
votes
3answers
8k views

Error: account unlock with HTTP access is forbidden when unlock an account in Geth console

personal.unlockAccount(eth.accounts[0],"") Error: account unlock with HTTP access is forbidden I run Geth in a Docker container and use docker exec -it bootstrap geth --datadir=~/.ethereum/...

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