Add WalletClient support to ExchangeOrderBuilder

Author: carlos-poly

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@polymarket/order-utils",
-  "version": "3.1.0",
+  "version": "3.2.0",
   "description": "Typescript utility for creating orders for Polymarket's CLOB",
   "author": "Liam Kovatch <liam@polymarket.com>",
   "homepage": "https://github.com/Polymarket/clob-order-utils",

src/exchange.order.builder.ts

@@ -7,7 +7,7 @@ import {
     PROTOCOL_VERSION,
 } from './exchange.order.const.ts';
 import type { EIP712TypedData } from './model/eip712.model.ts';
-import { hashTypedData } from 'viem';
+import { hashTypedData, type WalletClient } from 'viem';
 import type {
     Order,
     OrderData,
@@ -18,13 +18,57 @@ import type {
 import { SignatureType } from './model/signature-types.model.ts';
 import { generateOrderSalt } from './utils.ts';
 
+type ExchangeSignerInput = Wallet | JsonRpcSigner | WalletClient;
+
+interface IExchangeSigner {
+    getAddress(): Promise<string>;
+    signTypedData(
+        domain: EIP712TypedData['domain'],
+        types: EIP712TypedData['types'],
+        value: EIP712TypedData['message'],
+        primaryType?: string
+    ): Promise<OrderSignature>;
+}
+
+function createExchangeSigner(signer: ExchangeSignerInput): IExchangeSigner {
+    if ('_signTypedData' in signer) {
+        return {
+            getAddress: async () => signer.getAddress(),
+            signTypedData: async (domain, types, value) =>
+                signer._signTypedData(domain, types, value),
+        };
+    }
+
+    if (!signer.account) {
+        throw new Error('walletClient.account is required');
+    }
+
+    const account = signer.account;
+
+    return {
+        getAddress: async () => account.address,
+        signTypedData: async (domain, types, value, primaryType) =>
+            signer.signTypedData({
+                account,
+                domain,
+                types,
+                primaryType: primaryType ?? 'Order',
+                message: value,
+            }),
+    };
+}
+
 export class ExchangeOrderBuilder {
+    private readonly exchangeSigner: IExchangeSigner;
+
     constructor(
         private readonly contractAddress: string,
         private readonly chainId: number,
-        private readonly signer: Wallet | JsonRpcSigner,
+        signer: ExchangeSignerInput,
         private readonly generateSalt = generateOrderSalt
-    ) {}
+    ) {
+        this.exchangeSigner = createExchangeSigner(signer);
+    }
 
     /**
      * build an order object including the signature.
@@ -64,7 +108,7 @@ export class ExchangeOrderBuilder {
             signer = maker;
         }
 
-        const signerAddress = await this.signer.getAddress();
+        const signerAddress = await this.exchangeSigner.getAddress();
         if (signer !== signerAddress) {
             throw new Error('signer does not match');
         }
@@ -136,10 +180,11 @@ export class ExchangeOrderBuilder {
      */
     buildOrderSignature(typedData: EIP712TypedData): Promise<OrderSignature> {
         delete typedData.types.EIP712Domain;
-        return this.signer._signTypedData(
+        return this.exchangeSigner.signTypedData(
             typedData.domain,
             typedData.types,
-            typedData.message
+            typedData.message,
+            typedData.primaryType
         );
     }
 

tests/src/exchange.order.builder.test.ts

@@ -1,5 +1,7 @@
 import { expect } from 'chai';
 import { Wallet } from '@ethersproject/wallet';
+import { createWalletClient, http } from 'viem';
+import { privateKeyToAccount } from 'viem/accounts';
 import { ExchangeOrderBuilder } from '../../src/exchange.order.builder.ts';
 import { generateOrderSalt } from '../../src/utils.ts';
 import type { Order, OrderData } from '../../src/model/order.model.ts';
@@ -885,4 +887,88 @@ describe('order builder', () => {
             });
         });
     });
+
+    describe('WalletClient signer support', () => {
+        const chainId = 80002;
+        const exchangeAddress = '0xdFE02Eb6733538f8Ea35D585af8DE5958AD99E40';
+        const privateKey =
+            '0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80';
+
+        it('buildOrder uses walletClient account address', async () => {
+            const account = privateKeyToAccount(privateKey);
+            const walletClient = createWalletClient({
+                account,
+                transport: http('http://127.0.0.1:8545'),
+            });
+
+            const builder = new ExchangeOrderBuilder(
+                exchangeAddress,
+                chainId,
+                walletClient,
+                generateOrderSalt
+            );
+
+            const order = await builder.buildOrder({
+                maker: account.address,
+                taker: '0x0000000000000000000000000000000000000000',
+                tokenId: '1234',
+                makerAmount: '100000000',
+                takerAmount: '50000000',
+                side: Side.BUY,
+                feeRateBps: '100',
+                nonce: '0',
+            } as OrderData);
+
+            expect(order.signer).equal(account.address);
+        });
+
+        it('buildOrderSignature signs with walletClient', async () => {
+            const account = privateKeyToAccount(privateKey);
+            const walletClient = createWalletClient({
+                account,
+                transport: http('http://127.0.0.1:8545'),
+            });
+
+            const builder = new ExchangeOrderBuilder(
+                exchangeAddress,
+                chainId,
+                walletClient,
+                () => '479249096354'
+            );
+
+            const order = await builder.buildOrder({
+                maker: account.address,
+                taker: '0x0000000000000000000000000000000000000000',
+                tokenId: '1234',
+                makerAmount: '100000000',
+                takerAmount: '50000000',
+                side: Side.BUY,
+                feeRateBps: '100',
+                nonce: '0',
+            } as OrderData);
+
+            const orderTypedData = builder.buildOrderTypedData(order);
+            const signature = await builder.buildOrderSignature(orderTypedData);
+
+            expect(signature).equal(
+                // eslint-disable-next-line max-len
+                '0x302cd9abd0b5fcaa202a344437ec0b6660da984e24ae9ad915a592a90facf5a51bb8a873cd8d270f070217fea1986531d5eec66f1162a81f66e026db653bf7ce1c'
+            );
+        });
+
+        it('throws if walletClient.account is missing', () => {
+            const walletClient = createWalletClient({
+                transport: http('http://127.0.0.1:8545'),
+            });
+
+            expect(() => {
+                new ExchangeOrderBuilder(
+                    exchangeAddress,
+                    chainId,
+                    walletClient,
+                    generateOrderSalt
+                );
+            }).to.throw('walletClient.account is required');
+        });
+    });
 });