Files
pezkuwi-subxt/substrate/frame/examples/kitchensink/src/lib.rs
T
gupnik 60c77a2e9a Adds syntax for marking calls feeless (#1926)
Fixes https://github.com/paritytech/polkadot-sdk/issues/1725

This PR adds the following changes:
1. An attribute `pallet::feeless_if` that can be optionally attached to
a call like so:
```rust
#[pallet::feeless_if(|_origin: &OriginFor<T>, something: &u32| -> bool {
	*something == 0
})]
pub fn do_something(origin: OriginFor<T>, something: u32) -> DispatchResult {
     ....
}
```
The closure passed accepts references to arguments as specified in the
call fn. It returns a boolean that denotes the conditions required for
this call to be "feeless".

2. A signed extension `SkipCheckIfFeeless<T: SignedExtension>` that
wraps a transaction payment processor such as
`pallet_transaction_payment::ChargeTransactionPayment`. It checks for
all calls annotated with `pallet::feeless_if` to see if the conditions
are met. If so, the wrapped signed extension is not called, essentially
making the call feeless.

In order to use this, you can simply replace your existing signed
extension that manages transaction payment like so:
```diff
- pallet_transaction_payment::ChargeTransactionPayment<Runtime>,
+ pallet_skip_feeless_payment::SkipCheckIfFeeless<
+	Runtime,
+	pallet_transaction_payment::ChargeTransactionPayment<Runtime>,
+ >,
```

### Todo
- [x] Tests
- [x] Docs
- [x] Prdoc

---------

Co-authored-by: Nikhil Gupta <>
Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Francisco Aguirre <franciscoaguirreperez@gmail.com>
Co-authored-by: Liam Aharon <liam.aharon@hotmail.com>
2023-11-13 19:14:41 +05:30

335 lines
11 KiB
Rust

// This file is part of Substrate.
// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//! # Kitchensink Example Pallet
//!
//! **This pallet serves as an example and is not meant to be used in production.**
//!
//! The kitchen-sink catalog of the the FRAME macros and their various syntax options.
//!
//! This example does not focus on pallet instancing, `dev_mode`, and does nto include any 'where'
//! clauses on `T`. These will both incur additional complexity to the syntax, but are not discussed
//! here.
#![cfg_attr(not(feature = "std"), no_std)]
// Re-export pallet items so that they can be accessed from the crate namespace.
pub use pallet::*;
#[cfg(test)]
mod tests;
#[cfg(feature = "runtime-benchmarks")]
mod benchmarking;
#[cfg(feature = "try-runtime")]
use sp_runtime::TryRuntimeError;
pub mod weights;
pub use weights::*;
#[frame_support::pallet]
pub mod pallet {
use super::*;
use frame_support::pallet_prelude::*;
use frame_system::pallet_prelude::*;
/// The config trait of the pallet. You can basically do anything with the config trait that you
/// can do with a normal rust trait: import items consisting of types, constants and functions.
///
/// A very common pattern is for a pallet to import implementations of traits such as
/// [`frame_support::traits::Currency`], [`frame_support::traits::fungibles::Inspect`] and
/// [`frame_support::traits::Get`]. These are all types that the pallet is delegating to the top
/// level runtime to provide to it.
///
/// The `FRAME`-specific syntax are:
///
/// * the use of `#[pallet::constant]`([`frame_support::procedural`]), which places a `Get`
/// implementation in the metadata.
/// * `type RuntimeEvent`, which is mandatory if your pallet has events. See TODO.
/// * Needless to say, because [`Config`] is bounded by [`frame_system::Config`], you can use
/// all the items from [`frame_system::Config`] as well, such as `AccountId`.
/// * `#[pallet::disable_frame_system_supertrait_check]` would remove the need for
/// `frame_system::Config` to exist, which you should almost never need.
#[pallet::config]
pub trait Config: frame_system::Config {
/// The overarching runtime event type.
type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
/// Type representing the weight of this pallet
type WeightInfo: WeightInfo;
/// This is a normal Rust type, nothing specific to FRAME here.
type Currency: frame_support::traits::fungible::Inspect<Self::AccountId>;
/// Similarly, let the runtime decide this.
fn some_function() -> u32;
/// And this
const FOO: u32;
/// This is a FRAME-specific item. It will be placed in the metadata of the pallet, and
/// therefore can be queried by offchain applications.
#[pallet::constant]
type InMetadata: Get<u32>;
}
/// Allows you to define some extra constants to be added into constant metadata.
#[pallet::extra_constants]
impl<T: Config> Pallet<T> {
#[allow(non_snake_case)]
fn SomeValue() -> u32 {
unimplemented!()
}
#[pallet::constant_name(OtherValue)]
fn arbitrary_name() -> u32 {
unimplemented!()
}
}
const STORAGE_VERSION: frame_support::traits::StorageVersion = StorageVersion::new(1);
/// The pallet struct. There's nothing special to FRAME about this; it can implement functions
/// in an impl blocks, traits and so on.
#[pallet::pallet]
#[pallet::without_storage_info]
#[pallet::storage_version(STORAGE_VERSION)]
pub struct Pallet<T>(_);
/// Allows you to define some origin for the pallet.
#[pallet::origin]
pub type Origin<T> = frame_system::RawOrigin<<T as frame_system::Config>::AccountId>;
// first, we showcase all the possible storage types, with most of their details.
/// A storage value. We mark this as unbounded, alter its prefix, and define a custom storage
/// getter for it.
///
/// The value is stored a single trie node, and therefore can be retrieved with a single
/// database access.
#[pallet::storage]
#[pallet::unbounded] // optional
#[pallet::storage_prefix = "OtherFoo"] // optional
#[pallet::getter(fn foo)] // optional
pub type Foo<T> = StorageValue<Value = u32>;
#[pallet::type_value]
pub fn DefaultForFoo() -> u32 {
1
}
#[pallet::storage]
pub type FooWithDefault<T> =
StorageValue<Value = u32, QueryKind = ValueQuery, OnEmpty = DefaultForFoo>;
/// A storage map. This creates a mapping from keys of type `u32` to values of type `u32`.
///
/// Keys and values can be iterated, albeit each value is stored under a unique trie key,
/// meaning that an iteration consists of many database accesses.
#[pallet::storage]
pub type Bar<T> = StorageMap<Hasher = Blake2_128Concat, Key = u32, Value = u32>;
/// Conceptually same as `StorageMap<>` where the key is a tuple of `(u32, u32)`. On top, it
/// provides some functions to iterate or remove items based on only the first key.
#[pallet::storage]
pub type Qux<T> = StorageDoubleMap<
Hasher1 = Blake2_128Concat,
Key1 = u32,
Hasher2 = Blake2_128Concat,
Key2 = u32,
Value = u32,
>;
/// Same as `StorageDoubleMap`, but with arbitrary number of keys.
#[pallet::storage]
pub type Quux<T> = StorageNMap<
Key = (
NMapKey<Blake2_128Concat, u8>,
NMapKey<Blake2_128Concat, u16>,
NMapKey<Blake2_128Concat, u32>,
),
Value = u64,
>;
/// In all of these examples, we chose a syntax where the storage item is defined using the
/// explicit generic syntax (`X = Y`). Alternatively:
#[pallet::storage]
pub type AlternativeSyntax<T> = StorageMap<_, Blake2_128Concat, u32, u32>;
/// Lastly, all storage items, as you saw, had to be generic over `T`. If they want to use an
/// item from `Config`, `<T: Config>` should be used.
#[pallet::storage]
pub type AlternativeSyntax2<T: Config> = StorageMap<_, Blake2_128Concat, T::AccountId, u32>;
/// The genesis config type. This allows the pallet to define how it should initialized upon
/// genesis.
///
/// It can be generic over `T` or not, depending on whether it is or not.
#[pallet::genesis_config]
pub struct GenesisConfig<T: Config> {
pub foo: u32,
pub bar: BlockNumberFor<T>,
}
impl<T: Config> Default for GenesisConfig<T> {
fn default() -> Self {
Self { foo: 0, bar: Default::default() }
}
}
/// Allows you to define how `genesis_configuration is built.
#[pallet::genesis_build]
impl<T: Config> BuildGenesisConfig for GenesisConfig<T> {
fn build(&self) {
Foo::<T>::put(self.foo);
}
}
/// The call declaration. This states the entry points that we handle. The
/// macro takes care of the marshalling of arguments and dispatch.
#[pallet::call]
impl<T: Config> Pallet<T> {
#[pallet::call_index(0)]
#[pallet::weight(T::WeightInfo::set_foo_benchmark())]
/// Marks this call as feeless if `new_foo` is zero.
#[pallet::feeless_if(|_origin: &OriginFor<T>, new_foo: &u32, _other_compact: &u128| -> bool {
*new_foo == 0
})]
pub fn set_foo(
_: OriginFor<T>,
new_foo: u32,
#[pallet::compact] _other_compact: u128,
) -> DispatchResult {
Foo::<T>::set(Some(new_foo));
Ok(())
}
}
/// The event type. This exactly like a normal Rust enum.
///
/// It can or cannot be generic over `<T: Config>`. Note that unlike a normal enum, if none of
/// the variants actually use `<T: Config>`, the macro will generate a hidden `PhantomData`
/// variant.
///
/// The `generate_deposit` macro generates a function on `Pallet` called `deposit_event` which
/// will properly convert the error type of your pallet into `RuntimeEvent` (recall `type
/// RuntimeEvent: From<Event<Self>>`, so it can be converted) and deposit it via
/// `frame_system::Pallet::deposit_event`.
#[pallet::event]
#[pallet::generate_deposit(pub fn deposit_event)]
pub enum Event<T: Config> {
/// A simple tuple style variant.
SomethingHappened(u32),
/// A simple struct-style variant. Note that we use `AccountId` from `T` because `T:
/// Config`, which by extension implies `T: frame_system::Config`.
SomethingDetailedHappened { at: u32, to: T::AccountId },
/// Another variant.
SomeoneJoined(T::AccountId),
}
/// The error enum. Must always be generic over `<T>`, which is expanded to `<T: Config>`.
#[pallet::error]
pub enum Error<T> {
SomethingWentWrong,
SomethingBroke,
}
/// All the possible hooks that a pallet can have. See [`frame_support::traits::Hooks`] for more
/// info.
#[pallet::hooks]
impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {
fn integrity_test() {}
fn offchain_worker(_n: BlockNumberFor<T>) {
unimplemented!()
}
fn on_initialize(_n: BlockNumberFor<T>) -> Weight {
unimplemented!()
}
fn on_finalize(_n: BlockNumberFor<T>) {
unimplemented!()
}
fn on_idle(_n: BlockNumberFor<T>, _remaining_weight: Weight) -> Weight {
unimplemented!()
}
fn on_runtime_upgrade() -> Weight {
unimplemented!()
}
#[cfg(feature = "try-runtime")]
fn pre_upgrade() -> Result<Vec<u8>, TryRuntimeError> {
unimplemented!()
}
#[cfg(feature = "try-runtime")]
fn post_upgrade(_state: Vec<u8>) -> Result<(), TryRuntimeError> {
unimplemented!()
}
#[cfg(feature = "try-runtime")]
fn try_state(_n: BlockNumberFor<T>) -> Result<(), TryRuntimeError> {
unimplemented!()
}
}
/// Allows you to define an enum on the pallet which will then instruct
/// `construct_runtime` to amalgamate all similarly-named enums from other
/// pallets into an aggregate enum.
#[pallet::composite_enum]
pub enum HoldReason {
Staking,
}
/// Allows the pallet to validate some unsigned transaction. See
/// [`sp_runtime::traits::ValidateUnsigned`] for more info.
#[pallet::validate_unsigned]
impl<T: Config> ValidateUnsigned for Pallet<T> {
type Call = Call<T>;
fn validate_unsigned(_: TransactionSource, _: &Self::Call) -> TransactionValidity {
unimplemented!()
}
fn pre_dispatch(_: &Self::Call) -> Result<(), TransactionValidityError> {
unimplemented!()
}
}
/// Allows the pallet to provide some inherent. See [`frame_support::inherent::ProvideInherent`]
/// for more info.
#[pallet::inherent]
impl<T: Config> ProvideInherent for Pallet<T> {
type Call = Call<T>;
type Error = MakeFatalError<()>;
const INHERENT_IDENTIFIER: [u8; 8] = *b"test1234";
fn create_inherent(_data: &InherentData) -> Option<Self::Call> {
unimplemented!();
}
fn is_inherent(_call: &Self::Call) -> bool {
unimplemented!()
}
}
}