RegionX

1. Introduction

RegionX is a project dedicated to developing components for the new Agile Coretime model. The goal of the project is to enable developer teams, researchers, and speculators to start trading, tracking, and analyzing the product Polkadot offers - Coretime.

This repository is establishing the smart contract components for creating a secondary Coretime market. This infrastructure is meant to be leveraged by any end-user product built around Coretime.

The repository currently contains two crucial components in the form of ink! contracts that are necessary for the creation of a flexible and decentralized Coretime market.

2. Core components

2.1 Cross-Chain Regions

From a procurement perspective, regions can be seen as NFT tokens representing ownership of Coretime. Each region is characterized by a defined set of attributes that encompass all its properties. The following is the list of these attributes:

• begin: Specifies the starting point of time from which a task assigned to the region can be scheduled on a core.
• end: Specifies the deadline until a task assigned to the region can be scheduled on a core.
• length: The duration of a region. Always equals to end - begin.
• core: The core index to which the region belongs.
• mask: The regularity parts in which this Region will be scheduled.
• owner: The owner of the region.
• paid: The payment for the region on the bulk market. Defined only for renewable regions. This is used to calculate the renewal price in the next bulk sale.

The module containing all region-related logic is the pallet-broker. Deployed as part of the Coretime chain runtime, this pallet serves to handle all the Bulk Coretime procurement logic in Polkadot.

Given that the Coretime chain does not have any kind of smart-contract support it is not possible to create a secondary market on the Coretime chain itself. For this reason we have to store all the secondary market logic on a separate parachain which supports contract deployment. Given that cross-chain NFT metadata transfer is still something that hasn't been resolved in the ecosystem we are implementing additional custom logic that will enable the transfer of regions acrross chains.

An explanation of our solution for transferring the metadata of regions acrross chains can be found on the RegionX wiki: Cross-Chain Regions.

2.2 Coretime Marketplace

The RegionX Coretime market utilizes an order-book model and integrates directly with the XcRegions contract. For a region to be listed on the market, it must be represented within the XcRegion contract.

The regions sold in the market are classified into two categories:

• Active regions. The tasks that are assigned to active regions can currently be performed on a Polkadot core.
• Inactive regions. These are the regions that will become active in the upcoming Bulk period. The regions purchased from the Coretime chain fall into this category until the start of the next Bulk period.

Region pricing

The formula used to calculate the price of a region listed for sale is as follows:

$$ r_{price}=(r_{end}- t)*(tp * c_{occupancy}) $$

Where:

• $r_{end}$: is the timeslice at which the region concludes
• $t$: represents the current timeslice
• $tp$: is the cost per timeslice defined by the seller upon listing the region on the market.
• $c_{occupancy}$: represents the proportion of the Core that is occupied by the region.

The contract doesn't store the entire region's price; instead, it records the price of its timeslice, which is determined at the time of listing the region.

3. Develop

1. Make sure to have the latest cargo contract.
2. Clone the GitHub repository:

git clone https://github.com/RegionX-Labs/RegionX.git

3. Compile and run unit tests

cd RegionX/
cargo build
cargo test

3. Build the contracts:

# To build the xc-regions contract:
cd contracts/xc-regions/
cargo contract build --release

# To build the xc-regions contract:
cd contracts/coretime-market/
cargo contract build --release

4. Running e2e-tests

Given that the xc-regions contract requires the underlying chain to implement the uniques pallet, specifying a custom contracts node is necessary when running e2e tests. For this purpose, we use the Astar local node from Coretime-Mock directory:

export CONTRACTS_NODE="~/Coretime-Mock/bin/astar-collator"

Once that is configured, we can proceed to run the e2e tests:

cargo test --features e2e-tests

Additionally, this repository contains e2e typescript tests that can be executed using the steps below:

# in a separate terminal run a the astar-collator node from Coretime-Mock 
cd Coretime-Mock/
./bin/astar-collator --dev

After the node is running in a separate terminal:

# generate the artifacts
npm run compile

npm run test

4. Deploy

For the xc-regions contract to function correctly, the chain on which it is deployed must implement the uniques pallet. Given that the pallet index of the uniques pallet can vary across different chains, it's crucial to correctly configure this index before building and deploying the contract. To achieve this, the following steps should be taken:

1. Determine the index of the uniques pallet
2. Go to the primitives/lib.rs file:
3. Configure the index correctly:

#[derive(scale::Encode, scale::Decode)]
pub enum RuntimeCall {

	#[codec(index = <CORRECT PALLET INDEX>)]
	Uniques(uniques::UniquesCall),
}

Once this is correctly configured, the contract can then be deployed.