@axis-markets/orderbook

Stellar smart contract for AXIS limit orderbook DEX.

Interface

fn last() -> u64 Get last order id

Returns

• Last created order id

---

fn order(id: u64) -> Option<Order> Fetch existing order

Arguments

• id - ID of the order to fetch

Returns

• Order fetched from the storage

---

fn trade(direction: TradeDirection, kind: OrderKind, trader: Address, amount: i128, selling: Address, buying: Address, price: i128, orders: Vec<u64>) -> (i128, i128, u64) Trade with DEX and create a limit order if the quote was not executed in full.

Arguments

• direction - Trade direction: Sell or Buy
• kind - Order type (Limit, Fill, FillOrKill)
• trader - Trader address
• amount - Amount of selling tokens to send for Sell orders or target amount of buying tokens to acquire for Buy orders
• selling - Token address sent by trader
• buying - Token address received by trader
• price - Price limit: minimum buying per 1 selling for Sell orders or maximum selling per 1 buying for Buy orders
• orders - Optional list of order IDs to match before creating the order on-chain

Returns

• Amount of sold tokens (actual selling-side spent)
• Amount of bought tokens (actual buying-side acquired)
• ID of the newly created order (0 if no order was created)

Panics

• If the trader has insufficient balance
• If any of the orders provided do not match selling/buying asset
• If the trade causes an overflow

---

fn cancel(id: u64, trader: Address) Cancel existing order

Arguments

• id - ID of the order to cancel
• trader - Trader address

Panics

• If trader is not the owner of the order

---

fn fill_order(trader: Address, taker_order_id: u64, orders: Vec<u64>) -> (i128, i128) Fill existing orders using another matching order from the orderbook

Arguments

• trader - Trader address
• taker_order_id - ID of the order that serves as a taker
• orders - List of order IDs to match before creating the order on chain

Returns

• Amount of sold tokens
• Amount of bought tokens

Panics

• If the taker order was not found
• If any of the orders provided do not match selling/buying asset
• If the trade causes an overflow

Order storage format

enum OrderKind {
    Limit = 1,
    Fill = 2,
    FillOrKill = 3,
}

enum TradeDirection {
    Sell = 1,
    Buy = 2,
}

struct Order {
    pub id: u64,
    //order type
    pub kind: OrderKind,
    //selling token address
    pub selling: Address,
    //buying token address
    pub buying: Address,
    //amount left to sell/buy
    pub amount: i128,
    //initial selling/buying amount
    pub quote: i128,
    //maker address
    pub owner: Address,
    //order price
    pub price: i128,
    //expiration timestamp (0 = no expiration)
    pub expires: u64
}

Trade format

struct Trade {
    pub id: u64,
    //order id
    pub order: u64,
    //trader account address
    pub taker: Address,
    //seller account address
    pub maker: Address,
    //sold asset address
    pub selling: Address,
    //bought asset address
    pub buying: Address,
    //sold tokens amount
    pub sold: i128,
    //bought tokens amount
    pub bought: i128,
}

Standard errors

enum OrderbookError {
    NotAuthorized = 701,
    InsufficientBalance = 702,
    OrderNotFound = 703,
    Overflow = 704,
    InvalidMatch = 705,
    InvalidPrice = 706,
}

Events

OrderEvent

Topics: ["AXIS", "order", action: Symbol, selling: Address, buying: Address]
Body: Order
Action: one of "created"|"updated"|"removed"

TradeEvent

Topics: ["AXIS", "trade", selling: Address, buying: Address]
Body: Trade

Deployment and TS Bindings

Build a contract

stellar contract build --optimize

Deploy it to the network, obtain contract ID.

And create TS bindings

stellar contract bindings typescript --output-dir ./bindings --contract-id {contract_id} --overwrite --network-passphrase "Test SDF Network ; September 2015" --rpc-url https://soroban-testnet.stellar.org