衬底框架V2如何使用pallet_timestamp

Question

遵循基板教程并声明托盘配置，如托盘lib.rs中所示

use pallet_timestamp as timestamp;

    #[pallet::config]
    pub trait Config: frame_system::Config + pallet_timestamp::Config{
        type Event: From<Event<Self>> + IsType<<Self as frame_system::Config>::Event>;
    }

Caego.toml中的配置

pallet-timestamp = { version = '3.0', default-features = false}

std = [
    'codec/std',
    'frame-support/std',
    'frame-system/std',
    'sp-runtime/std',
    'pallet-timestamp/std',
    'log/std',
]

我需要使用pallet_timestamp获得时间戳

#[pallet::call]
impl<T: Config> Pallet<T> {

        #[pallet::weight(0)]
        pub fn update_recoed(origin: OriginFor<T>, record: Vec<u8>) -> DispatchResultWithPostInfo {
            let pallet_time = <timestamp::Module<T>>::get(); // Error
            Ok(().into())
        }
}

如何访问基板托盘V2中的时间？

Answer 1

与其像你所展示的那样直接使用托盘，不如使用托盘和托盘松耦合所提供的两个特性之一。

我提到的两个特征可以在pallet_timestamp 源代码中找到

impl<T: Config> Time for Pallet<T> {
    type Moment = T::Moment;

    /// Before the first set of now with inherent the value returned is zero.
    fn now() -> Self::Moment {
        Self::now()
    }
}

/// Before the timestamp inherent is applied, it returns the time of previous block.
///
/// On genesis the time returned is not valid.
impl<T: Config> UnixTime for Pallet<T> {
    fn now() -> core::time::Duration {
        // now is duration since unix epoch in millisecond as documented in
        // `sp_timestamp::InherentDataProvider`.
        let now = Self::now();
        sp_std::if_std! {
            if now == T::Moment::zero() {
                log::error!(
                    target: "runtime::timestamp",
                    "`pallet_timestamp::UnixTime::now` is called at genesis, invalid value returned: 0",
                );
            }
        }
        core::time::Duration::from_millis(now.saturated_into::<u64>())
    }
}

要使用这一点，您应该在新的托盘中执行以下操作：

1. 更新您的配置，使其具有新的配置，该配置使用了以下特性之一。您不需要将托盘紧密地连接到pallet_timestamp

use frame_support::traits::UnixTime;

#[pallet::config]
pub trait Config: frame_system::Config {
    type Event: From<Event<Self>> + IsType<<Self as frame_system::Config>::Event>;
    type TimeProvider: UnixTime;
}

1. 然后，在托盘的任何地方，您都可以调用T::TimeProvider::now()，以毫秒为单位将unix时间作为u64返回。

let time: u64 = T::TimeProvider::now().as_secs();

1. 为此，您需要将pallet_timstamp托盘插入到"TimeProvider“中。当您impl您的my_pallet::Config时，您可以通过配置它来做到这一点。

impl my_pallet::Config for Runtime {
    type Event = Event;
    type TimeProvider = pallet_timestamp::Pallet<Runtime>;
    // Or more easily just `Timestamp` assuming you used that name in `construct_runtime!`
}