STREAM-1597: account for transfer fees when creating Airdrops (#177)

* STREAM-1597: account for transfer fees when creating Airdrops * bump * move calculateAmountWithTransferFees to a function
streamflow-finance · May 24, 2024 · 9e892b3 · 9e892b3
1 parent c769b8b
commit 9e892b3
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Showing 8 changed files with 79 additions and 17 deletions.
diff --git a/lerna.json b/lerna.json
@@ -2,6 +2,6 @@
   "packages": [
     "packages/*"
   ],
-  "version": "6.3.7",
+  "version": "6.3.8",
   "$schema": "node_modules/lerna/schemas/lerna-schema.json"
 }
diff --git a/packages/common/package.json b/packages/common/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@streamflow/common",
-  "version": "6.3.7",
+  "version": "6.3.8",
   "description": "Common utilities and types used by streamflow packages.",
   "homepage": "https://github.com/streamflow-finance/js-sdk/",
   "main": "dist/index.js",

diff --git a/packages/distributor/package.json b/packages/distributor/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@streamflow/distributor",
-  "version": "6.3.7",
+  "version": "6.3.8",
   "description": "JavaScript SDK to interact with Streamflow Airdrop protocol.",
   "homepage": "https://github.com/streamflow-finance/js-sdk/",
   "main": "dist/index.js",

diff --git a/packages/distributor/solana/client.ts b/packages/distributor/solana/client.ts
@@ -1,6 +1,12 @@
 import BN from "bn.js";
 import PQueue from "p-queue";
-import { ASSOCIATED_TOKEN_PROGRAM_ID, NATIVE_MINT, createTransferCheckedInstruction } from "@solana/spl-token";
+import {
+  ASSOCIATED_TOKEN_PROGRAM_ID,
+  NATIVE_MINT,
+  createTransferCheckedInstruction,
+  createTransferCheckedWithFeeInstruction,
+  getTransferFeeConfig,
+} from "@solana/spl-token";
 import {
   Connection,
   PublicKey,
@@ -45,6 +51,7 @@ import {
 } from "./generated/instructions";
 import { ClaimStatus, MerkleDistributor } from "./generated/accounts";
 import {
+  calculateAmountWithTransferFees,
   getClaimantStatusPda,
   getDistributorPda,
   getEventAuthorityPda,
@@ -123,6 +130,7 @@ export default class SolanaDistributorClient {
     const ixs: TransactionInstruction[] = prepareBaseInstructions(this.connection, extParams);
     const mint = extParams.isNative ? NATIVE_MINT : new PublicKey(data.mint);
     const { mint: mintAccount, tokenProgramId } = await getMintAndProgram(this.connection, mint);
+    const transferFeeConfig = getTransferFeeConfig(mintAccount);
     const distributorPublicKey = getDistributorPda(this.programId, mint, data.version);
     const tokenVault = await ata(mint, distributorPublicKey, tokenProgramId);
     const senderTokens = await ata(mint, extParams.invoker.publicKey, tokenProgramId);
@@ -161,18 +169,41 @@ export default class SolanaDistributorClient {
     }
 
     ixs.push(newDistributor(args, accounts, this.programId));
-    ixs.push(
-      createTransferCheckedInstruction(
-        senderTokens,
-        mint,
-        tokenVault,
-        extParams.invoker.publicKey,
+
+    if (transferFeeConfig) {
+      const { transferAmount, feeCharged } = await calculateAmountWithTransferFees(
+        this.connection,
+        transferFeeConfig,
         BigInt(data.maxTotalClaim.toString()),
-        mintAccount.decimals,
-        undefined,
-        tokenProgramId,
-      ),
-    );
+      );
+
+      ixs.push(
+        createTransferCheckedWithFeeInstruction(
+          senderTokens,
+          mint,
+          tokenVault,
+          extParams.invoker.publicKey,
+          transferAmount,
+          mintAccount.decimals,
+          feeCharged,
+          undefined,
+          tokenProgramId,
+        ),
+      );
+    } else {
+      ixs.push(
+        createTransferCheckedInstruction(
+          senderTokens,
+          mint,
+          tokenVault,
+          extParams.invoker.publicKey,
+          BigInt(data.maxTotalClaim.toString()),
+          mintAccount.decimals,
+          undefined,
+          tokenProgramId,
+        ),
+      );
+    }
 
     return { distributorPublicKey, ixs };
   }

diff --git a/packages/distributor/solana/constants.ts b/packages/distributor/solana/constants.ts
@@ -1,5 +1,7 @@
 import { ICluster } from "@streamflow/common";
 
+export const ONE_IN_BASIS_POINTS = BigInt(10_000);
+
 export const DISTRIBUTOR_PROGRAM_ID = {
   [ICluster.Devnet]: "MErKy6nZVoVAkryxAejJz2juifQ4ArgLgHmaJCQkU7N",
   [ICluster.Mainnet]: "MErKy6nZVoVAkryxAejJz2juifQ4ArgLgHmaJCQkU7N",

diff --git a/packages/distributor/solana/utils.ts b/packages/distributor/solana/utils.ts
@@ -1,9 +1,13 @@
+import { TransferFeeConfig } from "@solana/spl-token";
 import { SignerWalletAdapter } from "@solana/wallet-adapter-base";
 import { Connection, Keypair, PublicKey, Transaction, VersionedTransaction } from "@solana/web3.js";
 import { ContractError } from "@streamflow/common";
 import { ConfirmationParams, signAndExecuteTransaction, ThrottleParams } from "@streamflow/common/solana";
 
 import { fromTxError } from "./generated/errors";
+import { ONE_IN_BASIS_POINTS } from "./constants";
+
+export const divCeilN = (n: bigint, d: bigint): bigint => n / d + (n % d ? BigInt(1) : BigInt(0));
 
 export function getDistributorPda(programId: PublicKey, mint: PublicKey, version: number): PublicKey {
   // Constructing the seed for the PDA
@@ -52,3 +56,28 @@ export async function wrappedSignAndExecuteTransaction(
     throw err;
   }
 }
+
+export async function calculateAmountWithTransferFees(
+  connection: Connection,
+  transferFeeConfig: TransferFeeConfig,
+  transferAmount: bigint,
+): Promise<{ transferAmount: bigint; feeCharged: bigint }> {
+  const epoch = await connection.getEpochInfo();
+  const transferFee =
+    epoch.epoch >= transferFeeConfig.newerTransferFee.epoch
+      ? transferFeeConfig.newerTransferFee
+      : transferFeeConfig.olderTransferFee;
+  const transferFeeBasisPoints = BigInt(transferFee.transferFeeBasisPoints);
+  let feeCharged = BigInt(0);
+
+  if (transferFeeBasisPoints !== BigInt(0)) {
+    const numerator = transferAmount * ONE_IN_BASIS_POINTS;
+    const denominator = ONE_IN_BASIS_POINTS - transferFeeBasisPoints;
+    const rawPreFeeAmount = divCeilN(numerator, denominator);
+    const fee = rawPreFeeAmount - transferAmount;
+    transferAmount = rawPreFeeAmount;
+    feeCharged = fee > transferFee.maximumFee ? transferFee.maximumFee : fee;
+  }
+
+  return { transferAmount, feeCharged };
+}
diff --git a/packages/eslint-config/package.json b/packages/eslint-config/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@streamflow/eslint-config",
-  "version": "6.3.7",
+  "version": "6.3.8",
   "license": "ISC",
   "main": "index.js",
   "files": [

diff --git a/packages/stream/package.json b/packages/stream/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@streamflow/stream",
-  "version": "6.3.7",
+  "version": "6.3.8",
   "description": "JavaScript SDK to interact with Streamflow protocol.",
   "homepage": "https://github.com/streamflow-finance/js-sdk/",
   "main": "dist/index.js",