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1500 questions
12
votes
2 answers
how to use ethereumjs-tx.js in a browser
I have been trying to use ethereumjs-tx in a browser. I have downloaded the browser builds from here https://github.com/ethereumjs/browser-builds/tree/master/dist
This is my code snippet
masrrew
- 121
- 1
- 3
12
votes
3 answers
Block header structure change under the Merge to Proof of Stake?
The yellow paper describes the below block header structure:
This includes difficulty, beneficiary, mixHash and nonce values. Presumably these will be redundant under Proof-of-Stake. How will the Block Header structure change under proof of stake?…
Lee
- 8,548
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- 46
- 80
12
votes
1 answer
What is a blockchain oracle?
What is a blockchain oracle for smart contracts? And why is it needed? I've seen a lot of posts about "how do oracles work", and "what is the oracle problem" but I don't understand what they are?
Keenan Olsen
- 359
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- 7
12
votes
4 answers
Are there any android wallets for Ethereum?
What Ethereum wallets are available for Android? Or which ones are still being developed?
Patoshi パトシ
- 4,800
- 7
- 45
- 93
12
votes
3 answers
How are we going to mitigate DDoS Attacks in Proof of Stake?
I would like to know if I am connected to the network as a validator, how I my node will be protected of DDoS attacks.
Jmiehau
- 973
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- 12
12
votes
2 answers
Can I send gas to another user?
Gas is purchased using Ether, does that mean I can send gas as a separate coin?
Patoshi パトシ
- 4,800
- 7
- 45
- 93
12
votes
4 answers
Is it possible to batch approve + transfer an ERC-20 token?
In our dapp, we currently have the following user flow:
Approve the Sablier contract to spend up to x ERC20 tokens
Transfer the x ERC20 tokens to the Sablier contract
This is not super bad UX, but it would certainly be nicer if users signed only…
Paul Razvan Berg
- 17,902
- 6
- 73
- 143
12
votes
5 answers
Invalid JSON RPC response: "" In Browser-Solidity
I'd like to connect private geth node from browser-solidity, however it returned the error Invalid JSON RPC response: "".
Please check the following picture for details.
Could you tell me how to solve the problem?
Toshi
- 2,357
- 8
- 23
- 34
12
votes
2 answers
Sending an ethereum transaction with ethers.js and metamask
I've tried two different ways, and have looked through ethers.js documentation, and I just haven't been able to figure it out. Does anyone have any suggestions? This is in a browser.
trans(web3,ethers);
async function…
Jared Smith
- 271
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12
votes
3 answers
How does the EVM find the entry of a called function?
I read the source code of go-ethereum and confused about how does the EVM find the entry of a called function.
As the specification said, the data field in a transaction specifies the function and the arguments.
So, in my comprehension, the specific…
rong jialei
- 761
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12
votes
2 answers
Pros and Cons of smart contract upgradable patterns
There have been quite many arguments around how to achieve smart contract updates like Upgradeable smart contracts.
I feel Proxycontract with Delegate-call is currently the most famous one. But aside from that, there are also other patterns.
So, I…
kohshiba
- 467
- 4
- 11
12
votes
2 answers
Solidity - Return value of Smart Contract Transaction
Why do Solidity transact functions not return any value?
Here is an easy example. I tested it in remix and web3.
pragma solidity ^0.4.25;
contract SimpleStorage {
uint public storedData;
constructor(uint initVal) public {
…
cqx
- 3,462
- 4
- 11
- 34
12
votes
4 answers
Using AWS CloudHSM to sign transactions
Does somebody knows how to properly use AWS CloudHSM to sign ethereum transactions (Keccak256)?
Lucas Yamamoto
- 185
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- 8
12
votes
2 answers
Difficulty and total difficulty
This is the info of one of the blocks in my private blockchain:
{
difficulty: 759585,
extraData: "0xd783010409844765746887676f312e362e32856c696e7578",
gasLimit: 4712388,
gasUsed: 0,
hash:…
galahad
- 3,920
- 3
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- 66
12
votes
2 answers
What datatype should I use for an IPFS address hash?
Here is an IPFS hash: QmTfCejgo2wTwqnDJs8Lu1pCNeCrCDuE4GAwkna93zdd7d. According to IPFS docs, they are base58 encoded, and I assume the Qm is metadata (because they all share this).
What is the most effective datatype to store one of these?
Edit:…
ZMitton
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- 34