support outputAmount (#222)

* support outputAmount

Signed-off-by: Gerhard Steenkamp <[email protected]>

* bump package

Signed-off-by: Gerhard Steenkamp <[email protected]>

* add changeset

Signed-off-by: Gerhard Steenkamp <[email protected]>

* use boolean

Signed-off-by: Gerhard Steenkamp <[email protected]>

* use allowUnmatchedDecimals in unit test

Signed-off-by: Gerhard Steenkamp <[email protected]>

---------

Signed-off-by: Gerhard Steenkamp <[email protected]>

Author: gsteenkamp89

.changeset/nasty-students-perform.md

@@ -0,0 +1,5 @@
+---
+"@across-protocol/app-sdk": patch
+---
+
+Add support for outputAmount field returned by suggested fees. this allows the safe handling of routes where input and output tokens do not have the same decimals

packages/sdk/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@across-protocol/app-sdk",
-  "version": "0.2.0",
+  "version": "0.2.1",
   "main": "./dist/index.js",
   "type": "module",
   "description": "The official SDK for integrating Across bridge into your dapp.",

packages/sdk/src/actions/getLimits.ts

@@ -30,6 +30,11 @@ type LimitsQueryParams = {
    * [Optional] The relayer address to simulate fill with. Defaults to the Across relayer.
    */
   relayer?: Address;
+  /**
+   * [Optional] Caller specifies whether to includes routes where input token
+   * and output token do not have the same decimals
+   */
+  allowUnmatchedDecimals?: boolean;
 };
 
 /**

packages/sdk/src/actions/getQuote.ts

@@ -158,6 +158,7 @@ export async function getQuote(params: GetQuoteParams): Promise<Quote> {
     message,
     logger,
     apiUrl,
+    allowUnmatchedDecimals: true,
   });
 
   logger?.debug("fees", fees);

packages/sdk/src/actions/getSuggestedFees.ts

@@ -45,6 +45,11 @@ export type SuggestedFeesQueryParams = {
    * [Optional] Whether to skip the amount limit check. Defaults to `false`.
    */
   skipAmountLimit?: boolean;
+  /**
+   * [Optional] Caller specifies whether to includes routes where input token
+   * and output token do not have the same decimals
+   */
+  allowUnmatchedDecimals?: boolean;
 };
 
 /**
@@ -146,6 +151,18 @@ export type GetSuggestedFeesReturnType = {
     maxDepositShortDelay: bigint;
     recommendedDepositInstant: bigint;
   };
+  inputToken: {
+    address: Address;
+    symbol: string;
+    decimals: number;
+    chainId: number;
+  };
+  outputToken: {
+    address: Address;
+    symbol: string;
+    decimals: number;
+    chainId: number;
+  };
 };
 
 /**
@@ -165,19 +182,16 @@ export async function getSuggestedFees({
     logger,
   );
 
-  const parsed = parseSuggestedFees(data);
-  return {
-    ...parsed,
-    outputAmount: BigInt(params.amount) - BigInt(data.totalRelayFee.total),
-  };
+  return parseSuggestedFees(data);
 }
 
 export function parseSuggestedFees(
   raw: SuggestedFeesApiResponse,
-): Omit<GetSuggestedFeesReturnType, "outputAmount"> {
+): GetSuggestedFeesReturnType {
   return {
     // ensure even unformatted values get passed through
     ...raw,
+    outputAmount: BigInt(raw.outputAmount),
     estimatedFillTimeSec: raw.estimatedFillTimeSec,
     capitalFeePct: Number(raw.capitalFeePct),
     capitalFeeTotal: BigInt(raw.capitalFeeTotal),
@@ -217,5 +231,17 @@ export function parseSuggestedFees(
       maxDepositShortDelay: BigInt(raw.limits.maxDepositShortDelay),
       recommendedDepositInstant: BigInt(raw.limits.recommendedDepositInstant),
     },
+    inputToken: {
+      address: raw.inputToken.address as Address,
+      symbol: raw.inputToken.symbol,
+      decimals: raw.inputToken.decimals,
+      chainId: raw.inputToken.chainId,
+    },
+    outputToken: {
+      address: raw.outputToken.address as Address,
+      symbol: raw.outputToken.symbol,
+      decimals: raw.outputToken.decimals,
+      chainId: raw.outputToken.chainId,
+    },
   };
 }

packages/sdk/src/api/suggested-fees.ts

@@ -47,6 +47,19 @@ export const suggestedFeesResponseJsonSchema = z.object({
     recommendedDepositInstant: bigNumberString,
   }),
   fillDeadline: numericString,
+  outputAmount: bigNumberString,
+  inputToken: z.object({
+    address: ethereumAddress,
+    symbol: z.string(),
+    decimals: z.number(),
+    chainId: z.number(),
+  }),
+  outputToken: z.object({
+    address: ethereumAddress,
+    symbol: z.string(),
+    decimals: z.number(),
+    chainId: z.number(),
+  }),
 });
 
 export type SuggestedFeesApiResponse = z.infer<

packages/sdk/src/utils/fetch.ts

@@ -24,7 +24,7 @@ export function buildSearchParams<
   for (const key in params) {
     const value = params[key];
 
-    if (!value) {
+    if (!isDefined(value)) {
       continue;
     }
 
@@ -45,6 +45,10 @@ export function isOk(res: Response) {
   return false;
 }
 
+export function isDefined<T>(value: T): value is NonNullable<T> {
+  return value !== undefined && value !== null ? true : false;
+}
+
 function makeFetcher(
   name: string,
   apiErrorHandler?: (

packages/sdk/test/unit/api/suggested-fees.test.ts

@@ -1,4 +1,7 @@
-import { getSuggestedFees } from "../../../src/actions/getSuggestedFees.js";
+import {
+  getSuggestedFees,
+  GetSuggestedFeesParams,
+} from "../../../src/actions/getSuggestedFees.js";
 import { suggestedFeesResponseJsonSchema } from "../../../src/api/suggested-fees.js";
 import { MAINNET_API_URL } from "../../../src/constants/index.js";
 import { buildSearchParams } from "../../../src/utils/fetch.js";
@@ -11,7 +14,8 @@ const params = {
   outputToken: "0x4200000000000000000000000000000000000006",
   destinationChainId: 10,
   amount: "2000000000000000000",
-} as const;
+  allowUnmatchedDecimals: true,
+} as const satisfies GetSuggestedFeesParams;
 
 describe("suggested-fees", async () => {
   // first test the raw response from the API.