feat: add signMetaTxCommitToBuyerOffer to meta-tx handler and mixin

e2e/tests/meta-tx.test.ts

@@ -1,5 +1,6 @@
 import { ZERO_ADDRESS } from "./../../packages/core-sdk/tests/mocks";
 import { BigNumberish } from "@ethersproject/bignumber";
+import { parseEther } from "@ethersproject/units";
 import { Wallet, BigNumber, constants } from "ethers";
 import { OfferFieldsFragment } from "../../packages/core-sdk/src/subgraph";
 import { mockCreateOfferArgs } from "../../packages/common/tests/mocks";
@@ -26,12 +27,19 @@ import {
   createOfferWithCondition,
   getCollectionMetadataUri,
   createRandomWallet,
-  META_TX_API_ID_VOUCHER
+  META_TX_API_ID_VOUCHER,
+  createDisputeResolver,
+  deployerWallet,
+  initSellerAndBuyerSDKs
 } from "./utils";
 import { CoreSDK, forwarder } from "../../packages/core-sdk/src";
 import EvaluationMethod from "../../contracts/protocol-contracts/scripts/domain/EvaluationMethod";
 import TokenType from "../../contracts/protocol-contracts/scripts/domain/TokenType";
-import { AuthTokenType, GatingType } from "../../packages/common";
+import { AuthTokenType, GatingType, OfferCreator } from "../../packages/common";
+import {
+  MSEC_PER_DAY,
+  MSEC_PER_SEC
+} from "./../../packages/common/src/utils/timestamp";
 
 const sellerWallet = seedWallet7; // be sure the seedWallet is not used by another test (to allow concurrent run)
 const sellerAddress = sellerWallet.address;
@@ -724,6 +732,198 @@ describe("meta-tx", () => {
     });
   });
 
+  describe("#signMetaTxCommitToBuyerOffer()", () => {
+    test("native exchange token buyer-initiated offer", async () => {
+      const exchangeToken = constants.AddressZero;
+      // drFeeAmount must be 0 so the seller doesn't need to deposit funds before
+      // committing via meta-tx (meta-tx can't carry ETH value)
+      const drFeeAmount = "0";
+
+      // Create a dispute resolver with zero fee (required for meta-tx compatibility)
+      const { fundedWallet: drFundedWallet } =
+        await initCoreSDKWithFundedWallet(sellerWallet);
+      const drAddress = drFundedWallet.address.toLowerCase();
+      const { disputeResolver } = await createDisputeResolver(
+        drFundedWallet,
+        deployerWallet,
+        {
+          assistant: drAddress,
+          admin: drAddress,
+          treasury: drAddress,
+          metadataUri: "",
+          escalationResponsePeriodInMS:
+            90 * MSEC_PER_DAY - 1 * MSEC_PER_SEC,
+          fees: [
+            {
+              feeAmount: drFeeAmount,
+              tokenAddress: exchangeToken,
+              tokenName: "Native"
+            }
+          ],
+          sellerAllowList: []
+        }
+      );
+
+      // Create fresh buyer/seller wallets
+      const {
+        sellerCoreSDK: sellerCoreSDKBuyer,
+        buyerCoreSDK: buyerCoreSDKBuyer,
+        sellerWallet: sellerFundedWallet
+      } = await initSellerAndBuyerSDKs(sellerWallet);
+
+      // Buyer creates a buyer-initiated offer.
+      // sellerDeposit must be 0 so the meta-tx relayer doesn't need to forward ETH value.
+      const buyerInitiatedOffer = await createOffer(buyerCoreSDKBuyer, {
+        creator: OfferCreator.Buyer,
+        quantityAvailable: 1,
+        disputeResolverId: disputeResolver.id,
+        exchangeToken,
+        sellerDeposit: "0"
+      });
+
+      // Buyer deposits offer.price to allow the seller to commit
+      const buyerDepositTx = await buyerCoreSDKBuyer.depositFunds(
+        buyerInitiatedOffer.buyerId,
+        buyerInitiatedOffer.price,
+        exchangeToken
+      );
+      await buyerCoreSDKBuyer.waitForGraphNodeIndexing(buyerDepositTx);
+
+      // Seller creates a seller account
+      await createSeller(sellerCoreSDKBuyer, sellerFundedWallet.address);
+      // No seller depositFunds needed: drFeeAmount = 0 and sellerDeposit = 0
+
+      const nonce = Date.now();
+
+      // Seller signs meta tx for commitToBuyerOffer
+      const { r, s, v, functionName, functionSignature } =
+        await sellerCoreSDKBuyer.signMetaTxCommitToBuyerOffer({
+          offerId: buyerInitiatedOffer.id,
+          sellerParams: {},
+          nonce
+        });
+
+      // Relayer executes meta tx on behalf of seller
+      const metaTx = await sellerCoreSDKBuyer.relayMetaTransaction({
+        functionName,
+        functionSignature,
+        nonce,
+        sigR: r,
+        sigS: s,
+        sigV: v
+      });
+      const metaTxReceipt = await metaTx.wait();
+      expect(metaTxReceipt.transactionHash).toBeTruthy();
+      expect(BigNumber.from(metaTxReceipt.effectiveGasPrice).gt(0)).toBe(true);
+    });
+
+    test("non-native exchange token buyer-initiated offer", async () => {
+      const exchangeToken = MOCK_ERC20_ADDRESS;
+      const drFeeAmount = parseEther("0.001");
+
+      // Create a dispute resolver with an ERC20 fee
+      const { fundedWallet: drFundedWallet } =
+        await initCoreSDKWithFundedWallet(sellerWallet);
+      const drAddress = drFundedWallet.address.toLowerCase();
+      const { disputeResolver } = await createDisputeResolver(
+        drFundedWallet,
+        deployerWallet,
+        {
+          assistant: drAddress,
+          admin: drAddress,
+          treasury: drAddress,
+          metadataUri: "",
+          escalationResponsePeriodInMS:
+            90 * MSEC_PER_DAY - 1 * MSEC_PER_SEC,
+          fees: [
+            {
+              feeAmount: drFeeAmount,
+              tokenAddress: exchangeToken,
+              tokenName: "ERC20"
+            }
+          ],
+          sellerAllowList: []
+        }
+      );
+
+      // Create fresh buyer/seller wallets
+      const {
+        sellerCoreSDK: sellerCoreSDKBuyer,
+        buyerCoreSDK: buyerCoreSDKBuyer,
+        sellerWallet: sellerFundedWallet,
+        buyerWallet: buyerFundedWallet
+      } = await initSellerAndBuyerSDKs(sellerWallet);
+
+      // Mint ERC20 tokens to fresh wallets (they start with 0 ERC20 balance)
+      await ensureMintedAndAllowedTokens(
+        [buyerFundedWallet, sellerFundedWallet],
+        undefined,
+        false
+      );
+
+      // Buyer creates a buyer-initiated offer with ERC20 exchange token.
+      // sellerDeposit is 0 to simplify the test setup.
+      const buyerInitiatedOffer = await createOffer(buyerCoreSDKBuyer, {
+        creator: OfferCreator.Buyer,
+        quantityAvailable: 1,
+        disputeResolverId: disputeResolver.id,
+        exchangeToken,
+        sellerDeposit: "0"
+      });
+
+      // Buyer approves ERC20 and deposits offer.price
+      await approveErc20Token(
+        buyerCoreSDKBuyer,
+        exchangeToken,
+        buyerInitiatedOffer.price
+      );
+      const buyerDepositTx = await buyerCoreSDKBuyer.depositFunds(
+        buyerInitiatedOffer.buyerId,
+        buyerInitiatedOffer.price,
+        exchangeToken
+      );
+      await buyerCoreSDKBuyer.waitForGraphNodeIndexing(buyerDepositTx);
+
+      // Seller creates a seller account
+      const seller = await createSeller(
+        sellerCoreSDKBuyer,
+        sellerFundedWallet.address
+      );
+
+      // Seller approves ERC20 and deposits drFeeAmount into the protocol
+      await approveErc20Token(sellerCoreSDKBuyer, exchangeToken, drFeeAmount);
+      const sellerDepositTx = await sellerCoreSDKBuyer.depositFunds(
+        seller.id,
+        drFeeAmount,
+        exchangeToken
+      );
+      await sellerCoreSDKBuyer.waitForGraphNodeIndexing(sellerDepositTx);
+
+      const nonce = Date.now();
+
+      // Seller signs meta tx for commitToBuyerOffer
+      const { r, s, v, functionName, functionSignature } =
+        await sellerCoreSDKBuyer.signMetaTxCommitToBuyerOffer({
+          offerId: buyerInitiatedOffer.id,
+          sellerParams: {},
+          nonce
+        });
+
+      // Relayer executes meta tx on behalf of seller
+      const metaTx = await sellerCoreSDKBuyer.relayMetaTransaction({
+        functionName,
+        functionSignature,
+        nonce,
+        sigR: r,
+        sigS: s,
+        sigV: v
+      });
+      const metaTxReceipt = await metaTx.wait();
+      expect(metaTxReceipt.transactionHash).toBeTruthy();
+      expect(BigNumber.from(metaTxReceipt.effectiveGasPrice).gt(0)).toBe(true);
+    });
+  });
+
   describe("#signMetaTxRedeemVoucher()", () => {
     test("non-native exchange token offer", async () => {
       const commitTx = await buyerCoreSDK.commitToOffer(offerToCommit.id);

packages/core-sdk/src/meta-tx/handler.ts

@@ -11,7 +11,8 @@ import {
   UpdateSellerArgs,
   OptInToSellerUpdateArgs,
   envConfigs,
-  abis
+  abis,
+  SellerOfferArgs
 } from "@bosonprotocol/common";
 import { storeMetadataOnTheGraph } from "../offers/storage";
 import { BigNumber, BigNumberish } from "@ethersproject/bignumber";
@@ -24,7 +25,8 @@ import {
 } from "../accounts/interface";
 import {
   bosonExchangeCommitHandlerIface,
-  bosonExchangeHandlerIface
+  bosonExchangeHandlerIface,
+  encodeCommitToBuyerOffer
 } from "../exchanges/interface";
 import {
   bosonOfferHandlerIface,
@@ -944,6 +946,22 @@ export async function signMetaTxCommitToConditionalOffer(
   };
 }
 
+export async function signMetaTxCommitToBuyerOffer(
+  args: BaseMetaTxArgs & {
+    offerId: BigNumberish;
+    sellerParams: SellerOfferArgs;
+  }
+): Promise<SignedMetaTx> {
+  const functionName =
+    "commitToBuyerOffer(uint256,(uint256,(address[],uint256[]),address))";
+
+  return signMetaTx({
+    ...args,
+    functionName,
+    functionSignature: encodeCommitToBuyerOffer(args.offerId, args.sellerParams)
+  });
+}
+
 export async function signMetaTxCancelVoucher(
   args: BaseMetaTxArgs & {
     exchangeId: BigNumberish;

packages/core-sdk/src/meta-tx/mixin.ts

@@ -634,6 +634,25 @@ export class MetaTxMixin<T extends Web3LibAdapter> extends BaseCoreSDK<T> {
     });
   }
 
+  /**
+   * Encodes and signs a meta transaction for `commitToBuyerOffer` that can be relayed.
+   * @param args - Meta transaction args.
+   * @returns Signature.
+   */
+  public async signMetaTxCommitToBuyerOffer(
+    args: Omit<
+      Parameters<typeof handler.signMetaTxCommitToBuyerOffer>[0],
+      "web3Lib" | "metaTxHandlerAddress" | "chainId"
+    >
+  ) {
+    return handler.signMetaTxCommitToBuyerOffer({
+      web3Lib: this._web3Lib,
+      metaTxHandlerAddress: this._protocolDiamond,
+      chainId: this._chainId,
+      ...args
+    });
+  }
+
   /**
    * Encodes and signs a meta transaction for `cancelVoucher` that can be relayed.
    * @param args - Meta transaction args.