This repository contains the implementation of the pallets and local node for the PBA's final exam. The task chosen for this assignment was Create a simple multi-token DEX.
The assignment consists of the following deliverables.
- DEX pallet, built from scratch
- Kitties NFT pallet, modified from an existing pallet
- Custom node to integrate the DEX, Kitties, and Assets pallets
The pallet has each extrinsic documented. To get a better understanding of what order of events are expected and which scenarios may lead to errors, check the tests.rs file.
It also exposes a trait interface SwapSimulation to allow other pallets to query the price of an amount of asset via a specific AMM. This takes into account slippage and fees, so the returned price should be as close as possible to the actual input amount required to get the desired amount of asset.
This has been extended from the original Substrate kitties tutorial to handle multi-assets. Users may choose which asset to quote their NFTs in. This is made possible by loosely coupling with Substrate's pallet-assets.
The tests.rs was modified to work with the new multi-asset mechanism. The file includes an example, at the very end, of how users may use the DEX pallet to aquire the assets necessary to buy a particular NFT.
This is a modification of the Substrate Node Template, incorporating the assets, dex, and kitties pallets into the runtime. The chain_spec.rs file was also modified so that accounts are endowed with some amount of assets to play with.
Build the node with cargo build --release in the root directory. After launching the node with ./target/release/node-template --dev, one can interact with the added pallets through Polkadot.js.