Use this tag for questions about the Polkadot blockchain network platform. General questions about Polkadot should be asked at https://substrate.stackexchange.com
Questions tagged [polkadot]
203 questions
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vote
0 answers
Access Substrate extrinsic data inside block-builder
During building the block from extrinsics in block-builder I need to access individual extrinsic data, namely signer's AccointId and a nonce. I assume these data a part of SignaturePayload of the Extrinsic trait but can not find a way to get…
Gleb Urvanov
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- 2
1
vote
1 answer
Is it possible to make external call from substrate contract
I want to make external http calls such as (eg. RPC calls to infura) from substrate contract. Is it possible?
If possible, then suggest me ways or some code snippet.
AsmitaSingh
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1
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3 answers
How to test events in substrate 3.0.0?
In substrate 2.0.1, its has following code:
mod simple_event {
pub use crate::Event;
}
impl_outer_event! {
pub enum TestEvent for TestRuntime {
simple_event,
frame_system,
…
Amiya Behera
- 2,210
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1
vote
1 answer
Polkadot websocket API doesn't listen for new blocks
Im using the polkadot.js api, running from a shell, and expecting to get multiple "Chain is at block #12345" messages. But i only get 1 of these messages and I do not know why.
I'm running a Polkadot node using the following docker command:
docker…
John
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1 answer
Polkadot-JS Import BIP44 Address w/Derivation?
SafePal S1 uses the following derivation path according to their website for Polkadot:
m/44h/354h/0h
SafePal is using BIP39/44 mnemonic phrase standard. I am trying to import my mnemonic phrase into the Polkadot-JS Chrome Extension but have no…
nukalov
- 1,309
- 13
- 18
1
vote
1 answer
How to set system properties in substrate blockchain for private network?
I am deploying my own private blockchain using the substrate code. In which how to set the token decimals and token symbol while deploying it?
Karthikeyan Thangavel
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- 14
1
vote
0 answers
How to call Constants Declared in Metadata Of substrate Node
I am using this library https://github.com/centrifuge/go-substrate-rpc-client where we fetch Latest Metadata via this call in my gloang code api.RPC.State.GetMetadataLatest(). This will return me metaData result for the connected substrate node from…
Anirudh Singh
- 11
- 2
1
vote
2 answers
Could not convert parameter `tx` between node and runtime: No such variant in enum MultiSignature
Hi I am getting the below error in polkadot-js, when I am trying to transfer the balance from Alice to Dave (or any other transfer).
Error :
balances.transferKeepAlive
1002: Verification Error: Execution: Could not convert parameter tx between node…
Kiran Kumar HM
- 41
- 3
1
vote
1 answer
Could not convert parameter `tx` between node and runtime: Error decoding field CheckMortality.0
I tried to use polkadot-js libray to run a simple app for transferring tokens between Dusty accounts on plasm. Source code and package.json for running the snippet is found on this git repo
Node version: v12.8.2
Yarn version: 1.22.5
const {…
Milton Cezar
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vote
1 answer
Why blocks dont finalized
We have substrate node with babe + grandpa consensus. We tried to run it on different computers and create a network. Everything works if we use the pre-installed accounts of Alice and Bob. We are trying to create our own config with our own keys.…
Daelon
- 33
- 4
1
vote
1 answer
How to properly use the LockableCurrency trait?
I am wondering how does the LockableCurrency work? Or more specifically, what are the WithdrawReasons? Is it just a marker or the value specified here is important for actually releasing the lock?
My use case is that I want to lock funds for…
Petr Mensik
- 26,874
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1
vote
0 answers
Is decentralized multichain exchange possible using oracles?
With substrate, we can build our own blockchain, but different blockchain can not communicate with each other, so polkadot is using a relay chain for it. But there is a limit to how many parachain can be attached to the relay…
Amiya Behera
- 2,210
- 19
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1
vote
3 answers
Error while build error[E0282]: type annotations needed
error[E0282]: type annotations needed
--> /home/amiya/.cargo/registry/src/github.com-1ecc6299db9ec823/sp-arithmetic-2.0.0/src/fixed_point.rs:541:9
|
541 | let accuracy = P::ACCURACY.saturated_into();
| …
Amiya Behera
- 2,210
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1
vote
1 answer
Error about connecting Substrate blockchains to Polkadot with Cumulus
I'm trying to connect my custom Substrate blockchains to Polkadot with Cumulus, by following the reference https://substrate.dev/cumulus-workshop/#/, I have successfully install Substrate, Relay Chain Node, and Collator Template.
Then, followed the…
leojail
- 307
- 3
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1
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1 answer
Getting the reward points of a validator by account
I am trying to find the reward points belonging to a validator. I started with this:
const activeEra = await api.query.staking.activeEra()
const rewardPoints = await api.query.staking.erasRewardPoints(activeEra.unwrap().index)
const…
lunr
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