Questions tagged [kovan]
Kovan is a new testnet for Ethereum using Parity's Proof of Authority consensus engine, which is immune to spam attacks as Ether supply is controlled by trusted parties and provides a consistent 4 second block time.
121
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Not receiving requested data from AccuWeather Weather Data Oracle
I'm attempting to pull weather data from the AccuWeather Weather Data Oracle (https://market.link/nodes/AccuWeather/integrations) through the Goerli Testnet. I've funded my contract with enough LINK ...
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1
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Function to store the strings from an api in an array and print the strings I want
I have this smart contract:
*//SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;
import '@chainlink/contracts/src/v0.8/ChainlinkClient.sol';
import '@chainlink/contracts/src/v0.8/ConfirmedOwner.sol'...
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360
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Fail with error 'SafeMath: subtraction overflow'
I am trying to use the "create" function from an LSP smart contract from the UMA protocol but I can not use it it always returns the "Fail with error 'SafeMath: subtraction overflow'&...
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2
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58
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initial transaction reverted, but cannot rebroadcast due to error: Transaction with the same hash was already imported
I'm trying to deploy my project to Kovan and the initial deployment tx reverted, but any attempt to deploy again is stopped by this error. Shouldn't the fact that my initial tx failed remove it from ...
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Question about finding token addresses to insert into a .sol Contract function
Ok so I have a .sol Contract that is trying to find arb between 2 dexes
I'm utilizing the Kovan Test Network -
this is the function
function estimateDualDexTrade(address _router1, address _router2, ...
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1
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749
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How to get Sushiswap and Uniswap prices from API for WETH/DAI on KOVAN?
Where can I find APIs to query data of WETH/DAI Prices on Uniswap and Sushiswap? For the mainnet, there is thegraph.com where one can query price data with pre-defined GraphQL queries, but I can't ...
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51
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Gas estimation reverts
I am quite new to blockchain programming and am trying to estimate the gas cost of calling a function from a smart contract.
I am using Web3 js and the Kovan network through an Infura node.
What am I ...
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4
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How to get failed transaction status code by using python web3?
Given transaction hash, i want to fetch Status code ('45' in this case, refer below image) with which transaction has failed using python web3.py. I already tried these methods, they don't seem to ...
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2
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9k
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What is this STF error when trying to use a function in a contract
I know there are many similiar questions but i can not figure out how to implement the 'approve' part in.
pragma solidity ^0.8;
pragma abicoder v2;
import '@uniswap/v3-periphery/contracts/libraries/...
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171
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How can I call a deployed smart contract on Kovan using Python?
The smart contract was written and deployed on Kovan using Remix IDE and injected Metamask Kovan test network account. However, I'll need python to deal with large input of a function in the smart ...
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54
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contract has not been deployed to detected network (network/artifact mismatch) when use truffle console --network kovan
i'm trying to call a function from contract that i deployed to kovan network, then when i used the truffle console --network kovan and tried to deploy my contract, it says that this contract has not ...
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381
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How to get detailed error for ValueError: {'code': -32016, 'data': 'Reverted', 'message': 'The execution failed due to an exception.'}
I deployed my Fund_me smart contract on Kovan testnet and I tried to call the withdraw function on it using web3, but I'm getting the error ValueError: {'code': -32016, 'data': 'Reverted', 'message': '...
- 101
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559
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Can't get Kovan testnet from Faucets.chain.link
I'm trying to get the ETH -> USD price from ChainLink but it's code requires the Kaven testnet.
But the problem is that the https://faucets.chain.link website isn't working correctly and it sends ...
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2
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672
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Error: This contract may be abstract, not implement an abstract parent's methods completely, not invoke an inherited contract's constructor correctly
Injected web3
Kovan 42 network
Remix IDE
This is from the freecodecamp.org tutorial on youtube
Here is the code :
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;
import "@chainlink/...
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186
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Kovan Test Net: not receiving test LINK
I tried to receive Link on the Kovan testnet two different ways, with the same result- No error message, it just continues to load endlessly.
https://kovan.chain.link/. a) "Send me 100 test link&...
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153
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problems deploying a contract on the Kovan network
Good evening, a couple of days ago I was able to execute this command without any problem and today, suddenly, I got this error. I don't understand what it means by "insufficient funds". ...
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2k
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Can I exchange test kovan eth to main eth? [duplicate]
I have some test eth. But I don't know how to use them. Can transfer as real eth Or what I have to do that please help me. Or I can sold them. In that case at how much cost can I sold.
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466
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How do I listen to changes for an ethereum address using websockets + RPC eth_subscribe method + postman
I am trying to listen for changes in a wallet balance on the Kovan testnet , so I have connected to a Kovan node using a node provider's websocket endpoint, I have no errors connecting, and no errors ...
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4
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1k
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Kovan Chainlink Faucet - Unable to locate the transaction hash
Etherscan says "Sorry, We are unable to locate this TxnHash" when sending LINK using both https://kovan.chain.link/ and https://faucets.chain.link/kovan
Waiting for a long time already but ...
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4
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431
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Error: Private key does not satisfy the curve requirements (ie. it is invalid)
I have a project working fine on truffle but when migrating to Kovan network, Getting the issue "Error: Private key does not satisfy the curve requirements (ie. it is invalid)" project is an ...
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1
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314
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Troubles interacting with Chainlink node on Kovan
I've been following instructions on running a local Chainlink node on Kovan. My environment is configured to Kovan through websockets via Infura and the node is both running and successfully accepts ...
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2
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5k
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Where to find and how to get Kovan USDC testnet tokens
I need USDC Kovan testnet tokens transffered to this address 0x2E9b971e336C825BC41b9FE87376E74f0B3345FE for testing purposes.
Token contract for this token is https://kovan.etherscan.io/token/...
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1
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71
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0x Kovan API returning 503 responses?
We have been using the Kovan 0x endpoint (https://kovan.api.0x.org/swap/v1) for a few months without trouble, but just started receiving HTTP 503 responses back today. Is the endpoint still supported ...
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628
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How to get the contract address based on the transaction hash?
I have the following code which returns the tx hash but when I call upon the receipt it returns null and thus cannot extract the address:
const privateKey1Buffer = Buffer.from(privateKey1, 'hex')
...
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1
answer
282
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Chainlink "Any API" Returning 0
I want to use the chainlink API features but I can not get the data. When I try to execute requestEthereumPrice function I get "uint256: 0" I am using Kovan test net and metamask.
pragma ...
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1
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747
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Connect local React frontend to contract on testnet (e.g Kovan)
I am new to this community and I had a question, in my opinion I think basic, but I have not found much information, see if you can help me.
I have been developing smart contracts, both in Remix and ...
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3
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1k
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Cannot obtain Kovan testnet Ether
Does anyone else have issues obtaining kovan ether? I have tried the following links only to recieve 0.01 Keth increments from app.mycrypto.com (when the site is up). The github sites do not respond
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4
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I keep getting nonce is too low when using truffle to call functions on contracts even though this works fine on remix.How can I fix this
I keep getting the nonce is too low when running functions with sub transactions on the kovan test net is there a way I can stop this from happening?these sub transactions are making transactions with ...
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1
answer
195
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I'm connecting to the wrong network but my configuration seems right
Trying to run truffle console I got this typical error:
I've checked my configuration and it seems OK to me (I don't know why truffle is trying to connect to 127.0.0.1). Here you can see my project:
...
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2
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1
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47
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Is there a decentralized way to intercommunicate between two Ethereum networks?
If I have Contract A deployed to the Rinkeby Test Netwok
If I have Contract B deployed to the Kovan Test Netwok
Then, can we program the contracts to interact with each other like Contract A invoking ...
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1
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1k
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Not receiving LINK from Chainlink kovan faucet
I attempted to get funds from kovan.chain.link to my metamask address and the money did not come through.
I got some errors as seen here: https://kovan.etherscan.io/tx/...
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0
answers
191
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Gas Estimation Error - Swap Contract
I'm working on developing a contract that automatically performs a swap and have been having an issue with the swap function. I finally got the contract deployed on Kovan, but have been getting the ...
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0
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87
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Contract method works on local but not on testnet
The following method, which works perfectly fine on my local ganache.
function someMethod() external view
returns (
bool someValue,
uint256 lastIndex,
uint256 totalTokens
...
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1
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0
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54
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AAVE Protocol v1 issue on reserve addresses with compound ctoken addresses
https://kovan.etherscan.io/tx/0xa7f5e857d1a9ecb4aca0714b24a70ca0942cc1a656c8e09b6d01bab9af4ec9e5
I am trying to make a transaction from DSProxy (Smart Wallet) on a contract
https://kovan.etherscan.io/...
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0
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445
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Issue with `TRANSFER_FROM_FAILED` when calling Uniswap contract - but I am approving the token!
My code is pretty simple
function swapForEth(address tokenAddress,
uint amountIn,
uint amountOutMin,
address to,
uint deadline) external onlyOwner payable {
require(IERC20(...
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2
answers
152
views
Exception:Reverted when swap by smart contrat with uniswap
Here is my code
pragma solidity ^0.8.2;
import "https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/interfaces/IUniswapV2Router02.sol";
contract Test_Swap{
address ...
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2
votes
2
answers
5k
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"Invalid Chain Id" on Kovan testnet
I'm attempting to initiate a transaction (transfer of ETH) from my main account to a test account on the Kovan Testnet, but I'm getting the error Returned error: Invalid chain id. from the following ...
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1
answer
757
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'Transaction nonce is too low. Try incrementing the nonce.' while following truffle tutorial
I ran into a nonce error on the last leg of this tutorial : https://www.trufflesuite.com/boxes/flashloan-box
I also supplemented the tutorial with this video on yt(fyi b/c some of the code comes from ...
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1
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407
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Transaction not showing on Kovan etherscan even after its status showed transaction mined and executed successfully
I have my contract deployed on Kovan Testnet and from remix IDE I called one of the functions of my smart contract through remix itself. Now, the status of transaction shows "transaction mined ...
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0
answers
228
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Is kovan network died? [duplicate]
Kovan's network faucet is inactive. I have only found a few "faucets" that give me 0.01 or 0.1 test Ether every 24 hours...
https://faucet.kovan.network
This is the Kovan Token contract. Its ...
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1
answer
4k
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Cant find sushiswap router address for Kovan testnet
Can anyone get me a routerV2 address for sushiswap on Kovan? The address given on sushi page is incorrect.Thanks
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2
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306
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Deploy contract to Kovan with brownie and infura
I'm trying to simply deploy a smart contract in Kovan network, i've used the export of the ID using export WEB3_INFURA_PROJECT_ID=xxxx but i'm getting this error
ValueError: The method ...
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2
answers
1k
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Seamless process to obtain test ether from faucet? [duplicate]
I am unable to successfully "Buy" Ether from a faucet for Ropsten or from Kovan. Is it me or do most people have issues setting up a testnet using Ropsten and/or Kovan? Can anyone help me ...
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1
answer
721
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Chainlink Price feed Main contract points to Kovan. Why? [closed]
I'm setting up price feeds with Chainlink.
https://docs.chain.link/docs/ethereum-addresses#mainnet
This page has sections: Mainnet, Rinkeby, Kovan.
Under Mainnet..
Clicking a pricefeed takes me to ..
...
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1
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220
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ETH transactions to presale contract keep failing
I'm trying to send some ETH to a presale smart contract on Kovan. Allowance has been set with presale address as a spender - with the exact same amount as the tokens allocated in the presale contract.
...
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0
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2
answers
1k
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Unable to interact with a contract on Kovan network on Remix IDE
I am working on a project and I have successfully deployed a smart contract on Kovan test network, but for some reason, I am not able to interact with it in JS code. So, now I want to access it ...
- 572
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25
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BlankToken Transaction
So i deployed my smart contract on Kovan Network using Remix IDE, i after successful compilation I added the arguments of the constructor to create the token, it deployed successfully but the issue ...
- 143
3
votes
1
answer
11k
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false Transaction mined but execution failed
I was trying to deploy my smart contract to Kovan test network using Remix IDE,although it compiles successfully but when I try to deploy it I get this error message
"false Transaction mined but ...
- 143
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1
answer
299
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Howto check sync with kovan testnet is complete or not?
I am trying to sync with Kovan testnet,
docker run --name eth -p 8546:8546 -v ~/ws-002-chainlink/ws00-docker-geth-ropsten:/geth -it ethereum/client-go:stable --testnet --syncmode light --ws --wsaddr 0....
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2
answers
152
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How can I obtain testnet REP for use on Kovan?
I would like to test the new version of Augur on the Kovan testnet. Where can I obtain testnet REP in order to do so? I found https://faucet.kovan.network/ for Kovan Ether (KETH) but cannot find ...
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