feat: introduce parseSwapV2 for Settler

src/index.ts

@@ -87,3 +87,8 @@ export async function parseSwap({
     callData: transaction.input,
   });
 }
+
+/**
+ * This function is specific to 0x API transactions on Settler.
+ */
+export { parseSwapV2 } from "./parseSwapV2";

src/parseSwapV2.ts

@@ -0,0 +1,140 @@
+import { erc20Abi, getAddress, formatUnits } from "viem";
+import type {
+  Chain,
+  Address,
+  Transport,
+  PublicClient,
+  TransactionReceipt,
+} from "viem";
+
+const NATIVE_TOKEN_ADDRESS = "0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE";
+
+type SupportedChainId = 1 | 8453;
+
+export const NATIVE_SYMBOL_BY_CHAIN_ID: { [key in SupportedChainId]: string } =
+  {
+    1: "ETH", // Ethereum
+    8453: "ETH", // Base
+  };
+
+export function isChainIdSupported(
+  chainId: number
+): chainId is SupportedChainId {
+  return [1, 10, 56, 137, 8453, 42161].includes(chainId);
+}
+
+export interface EnrichLogsArgs {
+  transactionReceipt: TransactionReceipt;
+  publicClient: PublicClient<Transport, Chain>;
+}
+export interface EnrichedLog {
+  to: Address;
+  from: Address;
+  symbol: string;
+  amount: string;
+  address: Address;
+  decimals: number;
+}
+
+export async function transferLogs({
+  publicClient,
+  transactionReceipt,
+}: EnrichLogsArgs): Promise<any> {
+  const EVENT_SIGNATURES = {
+    Transfer:
+      "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
+  } as const;
+  const { logs } = transactionReceipt;
+  const transferLogsAddresses = logs
+    .filter((log) => log.topics[0] === EVENT_SIGNATURES.Transfer)
+    .map((log) => ({ ...log, address: getAddress(log.address) }));
+  const contracts = [
+    ...transferLogsAddresses.map((log) => ({
+      abi: erc20Abi,
+      address: log.address,
+      functionName: "symbol",
+    })),
+    ...transferLogsAddresses.map((log) => ({
+      abi: erc20Abi,
+      address: log.address,
+      functionName: "decimals",
+    })),
+  ];
+  const results = await publicClient.multicall({ contracts });
+  const midpoint = Math.floor(results.length / 2);
+  const enrichedLogs = transferLogsAddresses
+    .map((log, index) => {
+      const symbol = results[index].result as string;
+      const decimals = results[midpoint + index].result as number;
+      const amount =
+        log.data === "0x" ? "0" : formatUnits(BigInt(log.data), decimals);
+      const { address, topics } = log;
+      const { 1: fromHex, 2: toHex } = topics;
+      const from = getAddress(convertHexToAddress(fromHex));
+      const to = getAddress(convertHexToAddress(toHex));
+
+      return { to, from, symbol, amount, address, decimals };
+    })
+    .filter((log) => log.amount !== "0");
+
+  return enrichedLogs;
+}
+
+function convertHexToAddress(hexString: string): string {
+  return `0x${hexString.slice(-40)}`;
+}
+
+export async function parseSwapV2({
+  publicClient,
+  transactionHash,
+}: {
+  publicClient: PublicClient<Transport, Chain>;
+  transactionHash: Address;
+}) {
+  const chainId = await publicClient.getChainId();
+  if (!isChainIdSupported(chainId)) {
+    throw new Error(`chainId ${chainId} is unsupported…`);
+  }
+
+  const transactionReceipt = await publicClient.getTransactionReceipt({
+    hash: transactionHash,
+  });
+  const { value } = await publicClient.getTransaction({
+    hash: transactionHash,
+  });
+  const isNativeSell = value > 0n;
+  const logs = await transferLogs({
+    publicClient,
+    transactionReceipt,
+  });
+
+  const input = logs[0];
+  const output = logs[logs.length - 1];
+  if (isNativeSell) {
+    const sellAmount = formatUnits(value, 18);
+    return {
+      tokenIn: {
+        symbol: NATIVE_SYMBOL_BY_CHAIN_ID[chainId],
+        amount: sellAmount,
+        address: NATIVE_TOKEN_ADDRESS,
+      },
+      tokenOut: {
+        symbol: output.symbol,
+        amount: output.amount,
+        address: output.address,
+      },
+    };
+  }
+  return {
+    tokenIn: {
+      symbol: input.symbol,
+      amount: input.amount,
+      address: input.address,
+    },
+    tokenOut: {
+      symbol: output.symbol,
+      amount: output.amount,
+      address: output.address,
+    },
+  };
+}

src/tests/parseSwapV2.test.ts

@@ -0,0 +1,202 @@
+import { http, createPublicClient } from "viem";
+import { mainnet } from "viem/chains";
+import { test, expect } from "vitest";
+import { parseSwapV2 } from "../index";
+
+require("dotenv").config();
+
+if (!process.env.ETH_MAINNET_RPC) {
+  throw new Error("An RPC URL required.");
+}
+
+const publicClient = createPublicClient({
+  chain: mainnet,
+  transport: http(process.env.ETH_MAINNET_RPC),
+});
+
+// https://etherscan.io/tx/0x2b9a12398613887e9813594e8583f488f0e8392d8e6e0ba8d9e140065826dd00
+test("parses swapped amounts case 1 (default)", async () => {
+  const transactionHash =
+    "0x2b9a12398613887e9813594e8583f488f0e8392d8e6e0ba8d9e140065826dd00";
+
+  const result = await parseSwapV2({
+    publicClient,
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "USDC",
+      amount: "30.084159",
+      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
+    },
+    tokenOut: {
+      symbol: "USDT",
+      amount: "30.069172",
+      address: "0xdAC17F958D2ee523a2206206994597C13D831ec7",
+    },
+  });
+});
+
+// https://etherscan.io/tx/0x76b744ab42b05b30624bd5027b4f7da841cdc357bb1d6ee74e3d9e049dd8a126
+test("parses swapped amounts case 2 (default)", async () => {
+  const transactionHash =
+    "0x76b744ab42b05b30624bd5027b4f7da841cdc357bb1d6ee74e3d9e049dd8a126";
+
+  const result = await parseSwapV2({
+    publicClient,
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "USDC",
+      amount: "1",
+      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
+    },
+    tokenOut: {
+      symbol: "WETH",
+      amount: "0.000280757770903965",
+      address: "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
+    },
+  });
+});
+
+// https://etherscan.io/tx/0x565e8e0582b620ee06618ee0b7705dc0e7f56dfd88b5eb3e008c0858f6f806d8
+test("parses swapped amounts case 3 (default)", async () => {
+  const transactionHash =
+    "0x565e8e0582b620ee06618ee0b7705dc0e7f56dfd88b5eb3e008c0858f6f806d8";
+
+  const result = await parseSwapV2({
+    publicClient,
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "USDC",
+      amount: "8.15942",
+      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
+    },
+    tokenOut: {
+      symbol: "WBTC",
+      amount: "0.00013188",
+      address: "0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599",
+    },
+  });
+});
+
+// https://etherscan.io/tx/0xd024750c7dcb99ace02c6b083c68d73dcfebdee252ccbeb1b83981b609693271
+test("parses swapped amounts case 4 (default)", async () => {
+  const transactionHash =
+    "0xd024750c7dcb99ace02c6b083c68d73dcfebdee252ccbeb1b83981b609693271";
+
+  const result = await parseSwapV2({
+    publicClient,
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "USDC",
+      amount: "335.142587",
+      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
+    },
+    tokenOut: {
+      symbol: "WETH",
+      amount: "0.105662100963455883",
+      address: "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
+    },
+  });
+});
+
+// https://etherscan.io/tx/0x4cbcf2e2512adb7e28f19f8cf28ddc29a9f9fea93c842cf3b735eeb526fe34b3
+test("parses swapped amounts case 5 (native sell token)", async () => {
+  const transactionHash =
+    "0x4cbcf2e2512adb7e28f19f8cf28ddc29a9f9fea93c842cf3b735eeb526fe34b3";
+
+  const result = await parseSwapV2({
+    publicClient,
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "ETH",
+      amount: "0.04",
+      address: "0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE",
+    },
+    tokenOut: {
+      symbol: "USDC",
+      amount: "126.580558",
+      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
+    },
+  });
+});
+
+// https://etherscan.io/tx/0x28c5bb3768bb64e81e1f3753ed1a8c30f0484a434d6c2b4af825d258ecb3bcf0
+test("parses swapped amounts case 6 (buy DNT 404 token)", async () => {
+  const transactionHash =
+    "0x28c5bb3768bb64e81e1f3753ed1a8c30f0484a434d6c2b4af825d258ecb3bcf0";
+
+  const result = await parseSwapV2({
+    publicClient,
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "USDC",
+      amount: "95",
+      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
+    },
+    tokenOut: {
+      symbol: "CHIB",
+      amount: "10.527633901274097318",
+      address: "0x7068263EDa099fB93BB3215c05e728c0b54b3137",
+    },
+  });
+});
+
+// https://etherscan.io/tx/0xb8beef6bf857f2fc22905b2872120abc634900b45941478aa9cf0ad1ceffcd67
+// https://gopluslabs.io/token-security/1/0xcf0c122c6b73ff809c693db761e7baebe62b6a2e
+test("parses swapped amounts case 6 (buy FoT token, FLOKI)", async () => {
+  const transactionHash =
+    "0xb8beef6bf857f2fc22905b2872120abc634900b45941478aa9cf0ad1ceffcd67";
+
+  const result = await parseSwapV2({
+    publicClient,
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "USDC",
+      amount: "31.580558",
+      address: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
+    },
+    tokenOut: {
+      symbol: "FLOKI",
+      amount: "172036.330384861",
+      address: "0xcf0C122c6b73ff809C693DB761e7BaeBe62b6a2E",
+    },
+  });
+});
+
+// https://explorer.celo.org/tx/0x615c5089f772a8f2074750e8c6070013d288af7681435aba1771f6bfc63d1286
+test("throws an error for unsupported chains)", async () => {
+  const transactionHash =
+    "0x615c5089f772a8f2074750e8c6070013d288af7681435aba1771f6bfc63d1286";
+
+  const publicClient = createPublicClient({
+    chain: mainnet,
+    transport: http("https://rpc.ankr.com/celo"),
+  });
+
+  expect(async () => {
+    await parseSwapV2({
+      publicClient,
+      transactionHash,
+    });
+  }).rejects.toThrowError("chainId 42220 is unsupported…");
+});