not all trait items implemented, missing: `RemoveItemsLimit`, `AssetIdParameter`, `CreateOrigin`, `CallbackHandle`

Question

i gonna add pallet-assets in my project but i faced this error :

error[E0046]: not all trait items implemented, missing: RemoveItemsLimit, AssetIdParameter, CreateOrigin, CallbackHandle --> /home/kianoush/projects/substrate_dex/runtime/src/lib.rs:289:1 | 289 | impl pallet_assets::Config for Runtime { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing RemoveItemsLimit, AssetIdParameter, CreateOrigin, CallbackHandle in implementation | = help: implement the missing item: type RemoveItemsLimit = Type; = help: implement the missing item: type AssetIdParameter = Type; = help: implement the missing item: type CreateOrigin = Type; = help: implement the missing item: type CallbackHandle = Type;

Repository

i did these steps :

1 - Add pallet-assets in Cargo.toml :

pallet-assets = { default-features = false, version = "4.0.0-dev", git = "https://github.com/paritytech/substrate.git", " branch" = "polkadot-v0.9.35" }

2 - Add this Config in runtime.rs :

   pub type AssetBalance = Balance;
pub type AssetId = u32;

impl pallet_assets::Config for Runtime {
    type RuntimeEvent = RuntimeEvent;
    type Balance = AssetBalance;
    type AssetId = AssetId;
    type Currency = Balances;
    type ForceOrigin = EnsureRoot<AccountId>;
    type AssetDeposit = ConstU128<1>;
    type AssetAccountDeposit = ConstU128<10>;
    type MetadataDepositBase = ConstU128<1>;
    type MetadataDepositPerByte = ConstU128<1>;
    type ApprovalDeposit = ConstU128<1>;
    type StringLimit = ConstU32<50>;
    type Freezer = ();
    type Extra = ();
    type WeightInfo = ();
}

whats the problem ? how can i solve this problem ?

Answer 1

Just reading the error, it seems you have incomplete configuration of pallet-assets. Here's what the pallet needs:

pub trait Config<I: 'static = ()>: Config {
    type RuntimeEvent: From<Event<Self, I>> + IsType<<Self as Config>::RuntimeEvent>;
    type Balance: Member + Parameter + AtLeast32BitUnsigned + Default + Copy + MaybeSerializeDeserialize + MaxEncodedLen + TypeInfo;
    type RemoveItemsLimit: Get<u32>;
    type AssetId: Member + Parameter + Copy + MaybeSerializeDeserialize + MaxEncodedLen;
    type AssetIdParameter: Parameter + Copy + From<Self::AssetId> + Into<Self::AssetId> + MaxEncodedLen;
    type Currency: ReservableCurrency<Self::AccountId>;
    type CreateOrigin: EnsureOriginWithArg<Self::RuntimeOrigin, Self::AssetId, Success = Self::AccountId>;
    type ForceOrigin: EnsureOrigin<Self::RuntimeOrigin>;
    type AssetDeposit: Get<<<Self as Config<I>>::Currency as Currency<<Self as SystemConfig>::AccountId>>::Balance>;
    type AssetAccountDeposit: Get<<<Self as Config<I>>::Currency as Currency<<Self as SystemConfig>::AccountId>>::Balance>;
    type MetadataDepositBase: Get<<<Self as Config<I>>::Currency as Currency<<Self as SystemConfig>::AccountId>>::Balance>;
    type MetadataDepositPerByte: Get<<<Self as Config<I>>::Currency as Currency<<Self as SystemConfig>::AccountId>>::Balance>;
    type ApprovalDeposit: Get<<<Self as Config<I>>::Currency as Currency<<Self as SystemConfig>::AccountId>>::Balance>;
    type StringLimit: Get<u32>;
    type Freezer: FrozenBalance<Self::AssetId, Self::AccountId, Self::Balance>;
    type Extra: Member + Parameter + Default + MaxEncodedLen;
    type CallbackHandle: AssetsCallback<Self::AssetId, Self::AccountId>;
    type WeightInfo: WeightInfo;
    type BenchmarkHelper: BenchmarkHelper<Self::AssetIdParameter>;
}

However, that said, if you switch your pallet-assets to use polkadot-v0.9.32, you don't need to provide the extra configuration and this should work with it.

Answer 2

This error means there are some trait items not implemented. The pallet_assets::Config is the trait being implemented on the runtime type. For example something like this

trait Foo {
    fn foo();
}

struct Bar;

impl Foo for Bar {}
// error: not all trait items implemented, missing: `foo`
```

as you can see when implementing the trait for the struct it doesn't contain the trait itemfn foo(). The solution would be to add fn foo() like

trait Foo {
    fn foo();
}

struct Bar;

impl Foo for Bar {
    fn foo() {} // ok!
}

So in your case the trait items not implemented are included in the error and the solution would be to add type RemoveItemsLimit = ();, type AssetIdParameter = ();, type CreateOrigin = ();, type CallbackHandle = (); to your trait implementation like:

 pub type AssetBalance = Balance;
pub type AssetId = u32;

impl pallet_assets::Config for Runtime {
    type RuntimeEvent = RuntimeEvent;
    type Balance = AssetBalance;
    type RemoveItemsLimit = ();
    type AssetId = AssetId;
    type AssetIdParameter = ();
    type Currency = Balances;
    type CreateOrigin = ();
    type ForceOrigin = EnsureRoot<AccountId>;
    type AssetDeposit = ConstU128<1>;
    type AssetAccountDeposit = ConstU128<10>;
    type MetadataDepositBase = ConstU128<1>;
    type MetadataDepositPerByte = ConstU128<1>;
    type ApprovalDeposit = ConstU128<1>;
    type StringLimit = ConstU32<50>;
    type Freezer = ();
    type Extra = ();
    type CallbackHandle = ();
    type WeightInfo = ();
}