feat: add fetch price from pyth tool

src/tools/index.ts

@@ -15,8 +15,9 @@ export * from "./get_token_data";
 export * from "./stake_with_jup";
 export * from "./fetch_price";
 export * from "./send_compressed_airdrop";
-
-export * from "./create_orca_single_sided_whirlpool";export * from "./raydium_create_ammV4";
+export * from "./create_orca_single_sided_whirlpool";
+export * from "./raydium_create_ammV4";
 export * from "./raydium_create_clmm";
 export * from "./raydium_create_cpmm";
-export * from "./openbook_create_market";
+export * from "./openbook_create_market";
+export * from "./pyth_fetch_price";

src/tools/pyth_fetch_price.ts

@@ -0,0 +1,48 @@
+import { PublicKey } from "@solana/web3.js";
+import { SolanaAgentKit } from "../index";
+import { Tool } from "langchain/tools";
+import { PriceServiceConnection } from "@pythnetwork/price-service-client";
+import BN from "bn.js";
+
+/**
+ * Fetch the price of a given price feed from Pyth
+ * @param agent SolanaAgentKit instance
+ * @param priceFeedID Price feed ID
+ * @returns Latest price value from feed
+ * 
+ * You can find priceFeedIDs here: https://www.pyth.network/developers/price-feed-ids#stable
+ */
+export async function pythFetchPrice(
+  agent: SolanaAgentKit,
+  priceFeedID: string
+) {
+  // get Hermes service URL from https://docs.pyth.network/price-feeds/api-instances-and-providers/hermes 
+  const stableHermesServiceUrl: string = "https://hermes.pyth.network";
+  const connection = new PriceServiceConnection(stableHermesServiceUrl);
+  const feeds = [priceFeedID];
+
+  try {
+    const currentPrice = await connection.getLatestPriceFeeds(feeds);
+  
+    if (currentPrice === undefined) {
+      throw new Error("Price data not available for the given token.");
+    }
+  
+    if (currentPrice.length === 0) {
+      throw new Error("Price data not available for the given token.");
+    }
+  
+    // get price and exponent from price feed
+    let price = new BN(currentPrice[0].getPriceUnchecked().price);
+    let exponent = new BN(currentPrice[0].getPriceUnchecked().expo);
+  
+    // convert to scaled price
+    let scaledPrice = price.div(new BN(10).pow(exponent));
+  
+    return scaledPrice.toString();
+  } catch (error: any) {
+    throw new Error(`Fetching price from Pyth failed: ${error.message}`);
+  }
+}
+
+

src/types/index.ts

@@ -77,3 +77,11 @@ export interface FetchPriceResponse {
   message?: string;
   code?: string;
 }
+
+export interface PythFetchPriceResponse {
+  status: "success" | "error";
+  priceFeedID: string;
+  price?: string;
+  message?: string;
+  code?: string;
+}