Files
pezkuwi-subxt/substrate/frame/im-online
Michal Kucharczyk 613420a035 frame: Enable GenesisConfig in no_std (#14108)
* frame: Default for GenesisConfig in no_std

`Default` for `GenesisConfig` will be required for no_std in no native
runtime world. It must be possible to instantiate default GenesisConfig
for pallets and runtime.

* ".git/.scripts/commands/fmt/fmt.sh"

* hash69 in no_std reverted

* derive(DefaultNoBound) for GenesisConfig used when possible

* treasury: derive(Default)

* Cargo.lock update

* genesis_config: compiler error improved

When std feature is not enabled for pallet, the GenesisConfig will be
defined, but serde::{Serialize,Deserialize} traits will not be
implemented.

The compiler error indicates the reason of latter errors.

This is temporary and serde traits will be enabled with together with
`serde` support in frame.

---------

Co-authored-by: command-bot <>
2023-05-20 07:34:23 +00:00
..

I'm online Module

If the local node is a validator (i.e. contains an authority key), this module gossips a heartbeat transaction with each new session. The heartbeat functions as a simple mechanism to signal that the node is online in the current era.

Received heartbeats are tracked for one era and reset with each new era. The module exposes two public functions to query if a heartbeat has been received in the current era or session.

The heartbeat is a signed transaction, which was signed using the session key and includes the recent best block number of the local validators chain as well as the NetworkState. It is submitted as an Unsigned Transaction via off-chain workers.

Interface

Public Functions

  • is_online - True if the validator sent a heartbeat in the current session.

Usage

use pallet_im_online::{self as im_online};

#[frame_support::pallet]
pub mod pallet {
    use super::*;
    use frame_support::pallet_prelude::*;
    use frame_system::pallet_prelude::*;

    #[pallet::pallet]
    pub struct Pallet<T>(_);

    #[pallet::config]
    pub trait Config: frame_system::Config + im_online::Config {}

    #[pallet::call]
    impl<T: Config> Pallet<T> {
        #[pallet::weight(0)]
        pub fn is_online(origin: OriginFor<T>, authority_index: u32) -> DispatchResult {
            let _sender = ensure_signed(origin)?;
            let _is_online = <im_online::Pallet<T>>::is_online(authority_index);
            Ok(())
        }
    }
}

Dependencies

This module depends on the Session module.

License: Apache-2.0