feat: update Liquidity Pool Fee by authorized Fee Manager

examples/dao-tx-example.ts

@@ -0,0 +1,37 @@
+import { getBackendBlockfrostLucidInstance, NetworkId } from "../src";
+import { Dao } from "../src/dao";
+
+async function main() {
+  const networkId: NetworkId = NetworkId.TESTNET;
+  const blockfrostProjectId = "<YOUR_BLOCKFROST_API_KEY>";
+  const blockfrostUrl = "https://cardano-preprod.blockfrost.io/api/v0";
+
+  const walletAddr = "<YOUR_WALLET_ADDRESS>";
+
+  const lucid = await getBackendBlockfrostLucidInstance(
+    networkId,
+    blockfrostProjectId,
+    blockfrostUrl,
+    walletAddr
+  );
+  lucid.selectWalletFromSeed("<YOUR_WALLET_SEED_PHRASE>");
+
+  const daoTx = new Dao(lucid);
+
+  const tx = await daoTx.updatePoolFeeTx({
+    managerAddress: walletAddr,
+    poolLPAsset: {
+      policyId: "d6aae2059baee188f74917493cf7637e679cd219bdfbbf4dcbeb1d0b",
+      tokenName:
+        "de0c83dde8b048b4883695cc3977619598e65a2d2c21ac2b57a5fb2494f19056",
+    },
+    newFeeA: 0.9,
+    newFeeB: 0.3,
+  });
+
+  const signedTx = await tx.sign().commit();
+  const txHash = await signedTx.submit();
+  console.log("Transaction submitted successfully: ", txHash);
+}
+
+main();

src/dao.ts

@@ -0,0 +1,89 @@
+import invariant from "@minswap/tiny-invariant";
+import { Addresses, Lucid, TxComplete } from "@spacebudz/lucid";
+import JSONBig from "json-bigint";
+
+import { Asset } from "./types/asset";
+import { DexV2Constant, MetadataMessage } from "./types/constants";
+import { NetworkId } from "./types/network";
+
+/**
+ * Request to update the trading fees for a liquidity pool.
+ * @property managerAddress - The address of the pool manager authorized to update fees
+ * @property poolLPAsset - The LP token asset identifying the pool
+ * @property newFeeA - The new fee for trading direction A as a percentage (0.05% - 20%)
+ * @property newFeeB - The new fee for trading direction B as a percentage (0.05% - 20%)
+ * @property version - Protocol version for the fee request format
+ */
+export type PoolFeeRequest = {
+  managerAddress: string;
+  poolLPAsset: Asset;
+  newFeeA: number;
+  newFeeB: number;
+  version: "1";
+};
+
+export type RequestPoolFeeOptions = {
+  request: Omit<PoolFeeRequest, "version">;
+};
+
+export class Dao {
+  private readonly lucid: Lucid;
+  private readonly networkId: NetworkId;
+
+  constructor(lucid: Lucid) {
+    this.lucid = lucid;
+    this.networkId =
+      lucid.network === "Mainnet" ? NetworkId.MAINNET : NetworkId.TESTNET;
+  }
+
+  /**
+   * Creates a transaction to update the trading fees for a liquidity pool.
+   * This method builds a transaction with metadata that requests fee changes for a pool.
+   * The transaction must be signed by the pool manager address.
+   */
+  async updatePoolFeeTx(
+    options: Omit<PoolFeeRequest, "version">
+  ): Promise<TxComplete> {
+    const { managerAddress, poolLPAsset, newFeeA, newFeeB } = options;
+    const newFeeABps = BigInt(Math.floor(newFeeA * 100));
+    const newFeeBBps = BigInt(Math.floor(newFeeB * 100));
+
+    invariant(
+      newFeeABps >= DexV2Constant.MIN_TRADING_FEE &&
+        newFeeABps <= DexV2Constant.MAX_TRADING_FEE,
+      `Liquidity Pool Fee A must be in 0.05% - 20%, actual: ${newFeeA}%`
+    );
+    invariant(
+      newFeeBBps >= DexV2Constant.MIN_TRADING_FEE &&
+        newFeeBBps <= DexV2Constant.MAX_TRADING_FEE,
+      `Liquidity Pool Fee B must be in 0.05% - 20%, actual: ${newFeeB}%`
+    );
+    const v2Configs = DexV2Constant.CONFIG[this.networkId];
+    invariant(
+      poolLPAsset.policyId === v2Configs.lpPolicyId,
+      `invalid Pool LP Token ${poolLPAsset}`
+    );
+
+    const feeRequestJSON = JSONBig.stringify({
+      managerAddress: managerAddress,
+      poolLPAsset: Asset.toDottedString(poolLPAsset),
+      newFeeA: newFeeABps.toString(),
+      newFeeB: newFeeBBps.toString(),
+      version: "1",
+    }).match(/.{1,64}/g);
+    const paymentCred = Addresses.addressToCredential(managerAddress);
+    invariant(
+      paymentCred.type === "Key",
+      "Manager address must be a key address"
+    );
+
+    return this.lucid
+      .newTx()
+      .addSigner(paymentCred.hash)
+      .attachMetadata(674, {
+        msg: [MetadataMessage.DAO_POOL_FEE_UPDATE],
+        extraData: feeRequestJSON,
+      })
+      .commit();
+  }
+}

src/types/asset.ts

@@ -38,6 +38,17 @@ export namespace Asset {
         return policyId + tokenName
     }
 
+    export function toDottedString(asset: Asset): string {
+        const { policyId, tokenName } = asset
+        if (policyId === "" && tokenName === "") {
+            return "lovelace"
+        }
+        if (asset.tokenName === "") {
+            return asset.policyId;
+        }
+        return `${asset.policyId}.${asset.tokenName}`;
+    }
+
     export function toPlutusData(asset: Asset): Constr<DataType> {
         const { policyId, tokenName } = asset
         return new Constr(0, [
@@ -51,8 +62,8 @@ export namespace Asset {
             throw new Error(`Index of Asset must be 0, actual: ${data.index}`)
         }
         invariant(
-          data.fields.length === 2,
-          `Asset fields length must be 2, actual: ${data.fields.length}`
+            data.fields.length === 2,
+            `Asset fields length must be 2, actual: ${data.fields.length}`
         );
         return {
             policyId: data.fields[0] as string,