Class: DexFees

Network-fee quote for GalaChain DEX methods, derived from a server-side DryRun.

The client only SIGNS the DryRun wrapper (with whatever GalaChainSigner it is given) and the backend forwards it to the gateway, where the simulated writes carry the fee; the backend never holds a key. Intended for wallets: the DTO quoted is the typed message a dApp handed over.

Example

const fees = new DexFees({ dexBackendBaseUrl }, new PrivateKeySigner(sessionKey));
const quote = await fees.quote(publicKey, 'RequestTrade', toChainDto(message), {
  contract: 'dex-contract',
});
const feeInGala = quote?.fees[0]?.feeInGala;

Constructors

Constructor

new DexFees(client, signer): DexFees

Parameters

Parameter	Type
client	DexFeesClient
signer	GalaChainSigner | undefined

Returns

DexFees

Methods

quote()

quote(callerPublicKey, method, message, options?): Promise<DexFeeQuote | null>

Quotes the network fee for method applied to message. The message is reduced with toChainDto first, so an EIP-712 approval message can be passed as is.

Resolves null when the BACKEND could not be reached or answered unusably (offline, 4xx/5xx, malformed body): a transport outcome, not a fee. Deciding what to charge when the chain is silent is the backend's job (it serves source: 'default'), so the client never substitutes a fee of its own, with ONE exception that mirrors the wallet: a dex-contract quote answered 403 or 404 means the contract has no fee route yet and resolves { source: 'default', '0' }. Never throws on transport, so a fee lookup cannot block or break a signing screen.

Parameters

Parameter	Type
callerPublicKey	string
method	"Swap" | "RequestTrade" | "AddLiquidity" | "RemoveLiquidity" | "CollectPositionFees" | "CreatePool"
message	Record<string, unknown>
options?	DexFeeQuoteOptions

Returns

Promise<DexFeeQuote | null>

Throws

GSwapSDKError NO_SIGNER when constructed without a signer; SIGNING_FAILED or KEY_PROVIDER_FAILED (a pre-send error, the original as cause) when the signer fails, for example a locked wallet.