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PSP22 Token Timelock

This example shows how you can reuse the implementation of PSP22 Token Timelock utility for PSP22. This contract will lock user's PSP22 tokens until the time specified, when they can withdraw them.

Step 1: Include dependencies​

Include openbrush as dependency in the cargo file or you can use default Cargo.toml template. After you need to enable default implementation of PSP22 via openbrush features.

openbrush = { version = "~2.1.0", default-features = false, features = ["psp22"] }

Step 2: Add imports and enable unstable feature​

Use openbrush::contract macro instead of ink::contract. Import everything from openbrush::contracts::psp22::utils::token_timelock.

#![cfg_attr(not(feature = "std"), no_std)]
#![feature(min_specialization)]

#[openbrush::contract]
pub mod my_psp22_token_timelock {
    use openbrush::contracts::psp22::utils::token_timelock::*;
    use ink_storage::traits::SpreadAllocate;
...

Step 3: Define storage​

Declare storage struct and declare the field related to the PSP22TokenTimelockStorage trait. Then you need to derive the PSP22TokenTimelockStorage trait and mark the corresponding field with #[PSP22TokenTimelockStorageField] attribute. Deriving this trait allows you to reuse the default implementation of and PSP22TokenTimelock.

#[ink(storage)]
#[derive(Default, SpreadAllocate, PSP22TokenTimelockStorage)]
pub struct MyPSP22TokenTimelock {
    #[PSP22TokenTimelockStorageField]
    timelock: PSP22TokenTimelockData
}

Step 4: Inherit logic​

Inherit the implementation of the PSP22TokenTimelock trait. You can customize (override) methods in this impl block.

impl PSP22TokenTimelock for MyPSP22TokenTimelock {}

Step 5: Define constructor​

Define constructor. Your implementation of PSP22TokenTimelock contract is ready!

impl MyPSP22TokenTimelock {
    #[ink(constructor)]
    pub fn new(token_address: AccountId, beneficiary: AccountId, release_time: Timestamp) -> Self {
        ink_lang::codegen::initialize_contract(|instance: &mut Self| {
            assert!(instance._init(token_address, beneficiary, release_time).is_ok());
        })
    }
}

You can check an example of the usage of PSP22 Token Timelock.

You can also check the documentation for the basic implementation of PSP22.