Igor Matuszewski
028f3d2674
* Backport paritytech/substrate#7381 * Bring back genesis storage build in aura/timestamp To not change spec version, see https://github.com/paritytech/substrate/pull/7686#discussion_r540032743 * Backport paritytech/substrate#7238 * Backport paritytech/substrate#7395 * Bump impl_version * Fix UI tests and bump trybuild dep See https://github.com/rust-lang/rust/pull/73996 Backports: https://github.com/paritytech/substrate/pull/7764 https://github.com/paritytech/substrate/pull/7656 * Partially backport paritytech/substrate#7838 * Release frame-support with a dep compilation fix * Bump patch level for remaining crates This is done because at the time of writing cargo-unleash does not fully support partial workspace publishing and mixes both local and crates.io versions of the packages, leading to errors in the release check workflow. * Backport paritytech/substrate#7854 ...to fix compilation error when using futures-* v0.3.9. * Adding Changelog entry for patch release Co-authored-by: Bastian Köcher <git@kchr.de> Co-authored-by: Benjamin Kampmann <ben@parity.io>
Timestamp Module
The Timestamp module provides functionality to get and set the on-chain time.
Overview
The Timestamp module allows the validators to set and validate a timestamp with each block.
It uses inherents for timestamp data, which is provided by the block author and validated/verified by other validators. The timestamp can be set only once per block and must be set each block. There could be a constraint on how much time must pass before setting the new timestamp.
NOTE: The Timestamp module is the recommended way to query the on-chain time instead of using an approach based on block numbers. The block number based time measurement can cause issues because of cumulative calculation errors and hence should be avoided.
Interface
Dispatchable Functions
set- Sets the current time.
Public functions
get- Gets the current time for the current block. If this function is called prior to setting the timestamp, it will return the timestamp of the previous block.
Config Getters
MinimumPeriod- Gets the minimum (and advised) period between blocks for the chain.
Usage
The following example shows how to use the Timestamp module in your custom module to query the current timestamp.
Prerequisites
Import the Timestamp module into your custom module and derive the module configuration trait from the timestamp trait.
Get current timestamp
use frame_support::{decl_module, dispatch};
use frame_system::ensure_signed;
pub trait Config: timestamp::Config {}
decl_module! {
pub struct Module<T: Config> for enum Call where origin: T::Origin {
#[weight = 0]
pub fn get_time(origin) -> dispatch::DispatchResult {
let _sender = ensure_signed(origin)?;
let _now = <timestamp::Module<T>>::get();
Ok(())
}
}
}
Example from the FRAME
The Session module uses the Timestamp module for session management.
Related Modules
License: Apache-2.0