1#![cfg_attr(not(feature = "std"), no_std)]23/// A FRAME pallet template with necessary imports45/// Feel free to remove or edit this file as needed.6/// If you change the name of this file, make sure to update its references in runtime/src/lib.rs7/// If you remove this file, you can remove those references89/// For more guidance on Substrate FRAME, see the example pallet10/// https://github.com/paritytech/substrate/blob/master/frame/example/src/lib.rs1112use frame_support::{decl_module, decl_storage, decl_event, decl_error, dispatch};13use system::ensure_signed;1415#[cfg(test)]16mod mock;1718#[cfg(test)]19mod tests;2021/// The pallet's configuration trait.22pub trait Trait: system::Trait {23 // Add other types and constants required to configure this pallet.2425 /// The overarching event type.26 type Event: From<Event<Self>> + Into<<Self as system::Trait>::Event>;27}2829// This pallet's storage items.30decl_storage! {31 // It is important to update your storage name so that your pallet's32 // storage items are isolated from other pallets.33 // ---------------------------------vvvvvvvvvvvvvv34 trait Store for Module<T: Trait> as TemplateModule {35 // Just a dummy storage item.36 // Here we are declaring a StorageValue, `Something` as a Option<u32>37 // `get(fn something)` is the default getter which returns either the stored `u32` or `None` if nothing stored38 Something get(fn something): Option<u32>;39 }40}4142// The pallet's events43decl_event!(44 pub enum Event<T> where AccountId = <T as system::Trait>::AccountId {45 /// Just a dummy event.46 /// Event `Something` is declared with a parameter of the type `u32` and `AccountId`47 /// To emit this event, we call the deposit function, from our runtime functions48 SomethingStored(u32, AccountId),49 }50);5152// The pallet's errors53decl_error! {54 pub enum Error for Module<T: Trait> {55 /// Value was None56 NoneValue,57 /// Value reached maximum and cannot be incremented further58 StorageOverflow,59 }60}6162// The pallet's dispatchable functions.63decl_module! {64 /// The module declaration.65 pub struct Module<T: Trait> for enum Call where origin: T::Origin {66 // Initializing errors67 // this includes information about your errors in the node's metadata.68 // it is needed only if you are using errors in your pallet69 type Error = Error<T>;7071 // Initializing events72 // this is needed only if you are using events in your pallet73 fn deposit_event() = default;7475 /// Just a dummy entry point.76 /// function that can be called by the external world as an extrinsics call77 /// takes a parameter of the type `AccountId`, stores it, and emits an event78 pub fn do_something(origin, something: u32) -> dispatch::DispatchResult {79 // Check it was signed and get the signer. See also: ensure_root and ensure_none80 let who = ensure_signed(origin)?;8182 // Code to execute when something calls this.83 // For example: the following line stores the passed in u32 in the storage84 Something::put(something);8586 // Here we are raising the Something event87 Self::deposit_event(RawEvent::SomethingStored(something, who));88 Ok(())89 }9091 /// Another dummy entry point.92 /// takes no parameters, attempts to increment storage value, and possibly throws an error93 pub fn cause_error(origin) -> dispatch::DispatchResult {94 // Check it was signed and get the signer. See also: ensure_root and ensure_none95 let _who = ensure_signed(origin)?;9697 match Something::get() {98 None => Err(Error::<T>::NoneValue)?,99 Some(old) => {100 let new = old.checked_add(1).ok_or(Error::<T>::StorageOverflow)?;101 Something::put(new);102 Ok(())103 },104 }105 }106 }107}difftreelog
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pallets/template/src/lib.rs3.5 KiBsourcehistory