Events

Registry events

Econia emits two types of registry events:

Event	Event handle	Field name
MarketRegistrationEvent	Registry	market_registration_events
RecognizedMarketEvent	RecognizedMarkets	recognized_market_events

Event handles for registry events are created via the @econia package account, and are stored as fields in key-able resources stored under the @econia account. Hence they can be easily queried via the Aptos node events by event handle API.

Market events

Schemas

Econia emits the following market events:

• user::CancelOrderEvent
• user::ChangeOrderSizeEvent
• user::FillEvent
• user::PlaceLimitOrderEvent
• user::PlaceMarketOrderEvent
• market::PlaceSwapOrderEvent

Unlike limit orders and market orders which are associated with a market account, swaps are not affiliated with a market account, and can be executed without a signature.

Hence to ensure comprehensive emission of events, Econia provides event handles as follows:

Handle wrapper	Associated table	Table indexed by
user::MarketEventHandlesForMarketAccount	user::MarketEventHandles	Market account ID
market::MarketEventHandlesForMarket	market::MarketEventHandles	Market ID
market::SwapperEventHandlesForMarket	market::SwapperEventHandles	Market ID

Since these event handles are stored inside tables they cannot be queried via the events by event handle API, and as such must be queried via the events by creation number API. Hence Econia provides associated event handle lookup view functions as follows:

Handle wrapper	Creation info view function
user::MarketEventHandlesForMarketAccount	user::get_market_event_handle_creation_numbers
market::MarketEventHandlesForMarket	market::get_market_event_handle_creation_info
market::SwapperEventHandlesForMarket	market::get_swapper_event_handle_creation_numbers

Placing a limit order

When a signing user or a custodian places a limit order, a user::PlaceLimitOrderEvent is emitted to the associated user::MarketEventHandlesForMarketAccount.

If the order fills across the spread then for each fill a user::FillEvent is emitted to the user::MarketEventHandlesForMarketAccount for both the maker and taker side.

If the limit order does not entirely fill during the function call in which it was placed, and if it is ineligible to post to the book, a user::CancelOrderEvent is emitted to the associated user::MarketEventHandlesForMarketAccount with one of the following cancel reasons:

Cancel reason	Description
CANCEL_REASON_SELF_MATCH_TAKER	A self match required cancelling the remaining order size
CANCEL_REASON_IMMEDIATE_OR_CANCEL	An immediate-or-cancel order did not fill completely across the spread
CANCEL_REASON_MAX_QUOTE_TRADED	No more quote coins can be traded even though there is still base asset to fill across the spread

If the order posts to the book and evicts the order with the lowest price time priority, then the evicted order is cancelled and a user::CancelOrderEvent is emitted to the associated user::MarketEventHandlesForMarketAccount with CANCEL_REASON_EVICTION.

Placing a market order

When a signing user or a custodian places a market order, a user::PlaceMarketOrderEvent is emitted to the associated user::MarketEventHandlesForMarketAccount.

For each fill a user::FillEvent is emitted to the user::MarketEventHandlesForMarketAccount for both the maker and taker side.

If the market order does not entirely fill during the function call in which it was placed, a user::CancelOrderEvent is emitted to the associated user::MarketEventHandlesForMarketAccount with one of the following cancel reasons:

Cancel reason	Description
CANCEL_REASON_SELF_MATCH_TAKER	A self match required cancelling the remaining order size
CANCEL_REASON_NOT_ENOUGH_LIQUIDITY	All liquidity on the book was taken by the order
CANCEL_REASON_MAX_QUOTE_TRADED	No more quote coins can be traded even though there is still base asset to fill across the spread

Placing a swap order (signing swapper)

When a signing swapper places a swap order, a market::PlaceSwapOrderEvent is emitted to the associated market::SwapperEventHandlesForMarket.

For each fill a user::FillEvent is emitted to the user::MarketEventHandlesForMarketAccount for the maker side, and to the market::SwapperEventHandlesForMarket for the taker side.

If the swap order does not fill the maximum specified base amount during the function call in which it was placed, a user::CancelOrderEvent is emitted to the associated market::SwapperEventHandlesForMarket with the same reasons as for a market order, as well as two additional cancel reasons that only apply to swaps:

Cancel reason	Description
CANCEL_REASON_TOO_SMALL_TO_FILL_LOT	No more base asset can be traded because the amount left to trade is less than one lot
CANCEL_REASON_VIOLATED_LIMIT_PRICE	The next order on the book to match against violated the swap order limit price

Placing a swap order (non-signing swapper)

When a swap order is not placed by a signing swapper, a market::PlaceSwapOrderEvent is emitted to the associated market::MarketEventHandlesForMarket.

For each fill a user::FillEvent is emitted to the user::MarketEventHandlesForMarketAccount for the maker side only.

If the swap order does not fill the maximum specified base amount during the function call in which it was placed, a user::CancelOrderEvent is emitted to the associated market::MarketEventHandlesForMarket with the same reasons as for a swap order with a signing swapper.

Maker self cancel

If, during a self match, the maker side of the order gets cancelled, a user::CancelOrderEvent is emitted to the associated user::MarketEventHandlesForMarketAccount with CANCEL_REASON_SELF_MATCH_MAKER.

Changing order size

When a signing user or a custodian manually changes the size of an open order, a user::ChangeOrderSizeEvent is emitted to the associated user::MarketEventHandlesForMarketAccount.

Manual order cancel

When a signing user or a custodian manually cancels an open order, a user::CancelOrderEvent is emitted to the associated user::MarketEventHandlesForMarketAccount with CANCEL_REASON_MANUAL_CANCEL.