Trait pallet_contracts::pallet::Config

pub trait Config: Config {
    type Time: Time;
    type Randomness: Randomness<Self::Hash, BlockNumberFor<Self>>;
    type Currency: Inspect<Self::AccountId> + Mutate<Self::AccountId> + MutateHold<Self::AccountId, Reason = Self::RuntimeHoldReason>;
    type RuntimeEvent: From<Event<Self>> + IsType<<Self as Config>::RuntimeEvent>;
    type RuntimeCall: Dispatchable<RuntimeOrigin = Self::RuntimeOrigin, PostInfo = PostDispatchInfo> + GetDispatchInfo + Decode + IsType<<Self as Config>::RuntimeCall>;
    type CallFilter: Contains<<Self as Config>::RuntimeCall>;
    type WeightPrice: Convert<Weight, <<Self as Config>::Currency as Inspect<<Self as Config>::AccountId>>::Balance>;
    type WeightInfo: WeightInfo;
    type ChainExtension: ChainExtension<Self> + Default;
    type Schedule: Get<Schedule<Self>>;
    type CallStack: Array<Item = Frame<Self>>;
    type DepositPerByte: Get<<<Self as Config>::Currency as Inspect<<Self as Config>::AccountId>>::Balance>;
    type DefaultDepositLimit: Get<<<Self as Config>::Currency as Inspect<<Self as Config>::AccountId>>::Balance>;
    type DepositPerItem: Get<<<Self as Config>::Currency as Inspect<<Self as Config>::AccountId>>::Balance>;
    type CodeHashLockupDepositPercent: Get<Perbill>;
    type AddressGenerator: AddressGenerator<Self>;
    type MaxCodeLen: Get<u32>;
    type MaxStorageKeyLen: Get<u32>;
    type MaxDelegateDependencies: Get<u32>;
    type UnsafeUnstableInterface: Get<bool>;
    type MaxDebugBufferLen: Get<u32>;
    type RuntimeHoldReason: From<HoldReason>;
    type Migrations: MigrateSequence;
    type Debug: Debugger<Self>;
    type Environment: Get<Environment<Self>>;
}

Configuration trait of this pallet.

The main purpose of this trait is to act as an interface between this pallet and the runtime in which it is embedded in. A type, function, or constant in this trait is essentially left to be configured by the runtime that includes this pallet.

Consequently, a runtime that wants to include this pallet must implement this trait.

Required Associated Types

type Time: Time

The time implementation used to supply timestamps to contracts through seal_now.

type Randomness: Randomness<Self::Hash, BlockNumberFor<Self>>

The generator used to supply randomness to contracts through seal_random.

Deprecated

Codes using the randomness functionality cannot be uploaded. Neither can contracts be instantiated from existing codes that use this deprecated functionality. It will be removed eventually. Hence for new pallet-contracts deployments it is okay to supply a dummy implementation for this type (because it is never used).

type Currency: Inspect<Self::AccountId> + Mutate<Self::AccountId> + MutateHold<Self::AccountId, Reason = Self::RuntimeHoldReason>

The fungible in which fees are paid and contract balances are held.

type RuntimeEvent: From<Event<Self>> + IsType<<Self as Config>::RuntimeEvent>

The overarching event type.

type RuntimeCall: Dispatchable<RuntimeOrigin = Self::RuntimeOrigin, PostInfo = PostDispatchInfo> + GetDispatchInfo + Decode + IsType<<Self as Config>::RuntimeCall>

The overarching call type.

type CallFilter: Contains<<Self as Config>::RuntimeCall>

Filter that is applied to calls dispatched by contracts.

Use this filter to control which dispatchables are callable by contracts. This is applied in addition to frame_system::Config::BaseCallFilter. It is recommended to treat this as a whitelist.

Stability

The runtime must make sure that all dispatchables that are callable by contracts remain stable. In addition Self::RuntimeCall itself must remain stable. This means that no existing variants are allowed to switch their positions.

Note

Note that dispatchables that are called via contracts do not spawn their own wasm instance for each call (as opposed to when called via a transaction). Therefore please make sure to be restrictive about which dispatchables are allowed in order to not introduce a new DoS vector like memory allocation patterns that can be exploited to drive the runtime into a panic.

type WeightPrice: Convert<Weight, <<Self as Config>::Currency as Inspect<<Self as Config>::AccountId>>::Balance>

Used to answer contracts’ queries regarding the current weight price. This is not used to calculate the actual fee and is only for informational purposes.

type WeightInfo: WeightInfo

Describes the weights of the dispatchables of this module and is also used to construct a default cost schedule.

type ChainExtension: ChainExtension<Self> + Default

Type that allows the runtime authors to add new host functions for a contract to call.

type Schedule: Get<Schedule<Self>>

Cost schedule and limits.

type CallStack: Array<Item = Frame<Self>>

The type of the call stack determines the maximum nesting depth of contract calls.

The allowed depth is CallStack::size() + 1. Therefore a size of 0 means that a contract cannot use call or instantiate. In other words only the origin called “root contract” is allowed to execute then.

This setting along with MaxCodeLen directly affects memory usage of your runtime.

type DepositPerByte: Get<<<Self as Config>::Currency as Inspect<<Self as Config>::AccountId>>::Balance>

The amount of balance a caller has to pay for each byte of storage.

Note

Changing this value for an existing chain might need a storage migration.

type DefaultDepositLimit: Get<<<Self as Config>::Currency as Inspect<<Self as Config>::AccountId>>::Balance>

Fallback value to limit the storage deposit if it’s not being set by the caller.

type DepositPerItem: Get<<<Self as Config>::Currency as Inspect<<Self as Config>::AccountId>>::Balance>

The amount of balance a caller has to pay for each storage item.

Note

Changing this value for an existing chain might need a storage migration.

type CodeHashLockupDepositPercent: Get<Perbill>

The percentage of the storage deposit that should be held for using a code hash. Instantiating a contract, or calling chain_extension::Ext::add_delegate_dependency protects the code from being removed. In order to prevent abuse these actions are protected with a percentage of the code deposit.

type AddressGenerator: AddressGenerator<Self>

The address generator used to generate the addresses of contracts.

type MaxCodeLen: Get<u32>

The maximum length of a contract code in bytes.

The value should be chosen carefully taking into the account the overall memory limit your runtime has, as well as the maximum allowed callstack depth. Look into the integrity_test() for some insights.

type MaxStorageKeyLen: Get<u32>

The maximum allowable length in bytes for storage keys.

type MaxDelegateDependencies: Get<u32>

The maximum number of delegate_dependencies that a contract can lock with chain_extension::Ext::add_delegate_dependency.

type UnsafeUnstableInterface: Get<bool>

Make contract callable functions marked as #[unstable] available.

Contracts that use #[unstable] functions won’t be able to be uploaded unless this is set to true. This is only meant for testnets and dev nodes in order to experiment with new features.

Warning

Do not set to true on productions chains.

type MaxDebugBufferLen: Get<u32>

The maximum length of the debug buffer in bytes.

type RuntimeHoldReason: From<HoldReason>

Overarching hold reason.

type Migrations: MigrateSequence

The sequence of migration steps that will be applied during a migration.

Examples

use pallet_contracts::migration::{v10, v11};
type Migrations = (v10::Migration<Runtime, Currency>, v11::Migration<Runtime>);

If you have a single migration step, you can use a tuple with a single element:

use pallet_contracts::migration::v10;
type Migrations = (v10::Migration<Runtime, Currency>,);

type Debug: Debugger<Self>

Note

For most production chains, it’s recommended to use the () implementation of this trait. This implementation offers additional logging when the log target “runtime::contracts” is set to trace.

type Environment: Get<Environment<Self>>

Type that bundles together all the runtime configurable interface types.

This is not a real config. We just mention the type here as constant so that its type appears in the metadata. Only valid value is ().

Implementors