/**
* Yahoo Finance API Service
* Free stock price fetching without authentication
*/
interface YahooQuote {
symbol: string;
regularMarketPrice: number;
regularMarketTime: number;
currency: string;
}
interface YahooFinanceResponse {
quoteResponse: {
result: Array<{
symbol: string;
regularMarketPrice?: number;
regularMarketPreviousClose?: number;
}>;
error: any;
};
}
/**
* Convert Indian stock symbols to Yahoo Finance format
* Examples:
* - RELIANCE -> RELIANCE.NS (NSE)
* - TCS -> TCS.NS (NSE)
* - INFY -> INFY.NS (NSE)
*/
function formatSymbolForYahoo(symbol: string, exchange: 'NSE' | 'BSE' = 'NSE'): string {
// Remove any existing suffix
const cleanSymbol = symbol.replace(/\.(NS|BO)$/i, '');
// Add appropriate suffix
// .NS for NSE (National Stock Exchange)
// .BO for BSE (Bombay Stock Exchange)
const suffix = exchange === 'BSE' ? '.BO' : '.NS';
return `${cleanSymbol}${suffix}`;
}
/**
* Fetch current prices for multiple symbols from Yahoo Finance
* @param symbols Array of stock symbols (e.g., ['RELIANCE', 'TCS', 'INFY'])
* @param exchange Exchange to use (NSE or BSE), defaults to NSE
* @returns Object mapping symbol to price
*/
export async function getCurrentPrices(
symbols: string[],
exchange: 'NSE' | 'BSE' = 'NSE'
): Promise<Record<string, number>> {
const prices: Record<string, number> = {};
if (symbols.length === 0) {
return prices;
}
try {
// Fetch prices one by one using v8/finance/chart endpoint (more reliable)
console.log(`[YahooFinance] Fetching prices for ${symbols.length} symbols...`);
for (const symbol of symbols) {
try {
const formattedSymbol = formatSymbolForYahoo(symbol, exchange);
// Use v8/finance/chart endpoint which is more stable
const url = `https://query1.finance.yahoo.com/v8/finance/chart/${formattedSymbol}?interval=1d&range=1d`;
const response = await fetch(url, {
headers: {
'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
'Accept': '*/*',
'Accept-Language': 'en-US,en;q=0.9',
'Referer': 'https://finance.yahoo.com',
},
signal: AbortSignal.timeout(5000), // 5 second timeout per symbol
});
if (!response.ok) {
console.warn(`[YahooFinance] HTTP error for ${symbol}: ${response.status}`);
prices[symbol] = 0;
continue;
}
const data = await response.json();
// Extract price from chart data
const result = data?.chart?.result?.[0];
const currentPrice = result?.meta?.regularMarketPrice
|| result?.meta?.previousClose
|| result?.indicators?.quote?.[0]?.close?.slice(-1)[0];
if (currentPrice && currentPrice > 0) {
prices[symbol] = currentPrice;
console.log(`[YahooFinance] ${symbol}: ₹${currentPrice.toFixed(2)}`);
} else {
prices[symbol] = 0;
console.warn(`[YahooFinance] No price data for ${symbol}`);
}
// Small delay between requests to avoid rate limiting
await new Promise(resolve => setTimeout(resolve, 100));
} catch (symbolError: any) {
console.error(`[YahooFinance] Error fetching ${symbol}:`, symbolError.message);
prices[symbol] = 0;
}
}
console.log(`[YahooFinance] Successfully fetched prices for ${Object.keys(prices).length} symbols`);
return prices;
} catch (error: any) {
console.error('[YahooFinance] Error fetching prices:', error.message);
// Return zero prices for all symbols on error
for (const symbol of symbols) {
prices[symbol] = 0;
}
return prices;
}
}
/**
* Fetch price for a single symbol
* @param symbol Stock symbol (e.g., 'RELIANCE')
* @param exchange Exchange to use (NSE or BSE)
* @returns Current price or 0 if not found
*/
export async function getCurrentPrice(
symbol: string,
exchange: 'NSE' | 'BSE' = 'NSE'
): Promise<number> {
const prices = await getCurrentPrices([symbol], exchange);
return prices[symbol] || 0;
}
/**
* Get detailed quote information for a symbol
* @param symbol Stock symbol
* @param exchange Exchange to use
* @returns Detailed quote data
*/
export async function getQuote(
symbol: string,
exchange: 'NSE' | 'BSE' = 'NSE'
): Promise<any> {
try {
const formattedSymbol = formatSymbolForYahoo(symbol, exchange);
const url = `https://query1.finance.yahoo.com/v7/finance/quote?symbols=${formattedSymbol}`;
const response = await fetch(url, {
headers: {
'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
'Accept': 'application/json',
'Accept-Language': 'en-US,en;q=0.9',
'Referer': 'https://finance.yahoo.com',
'Origin': 'https://finance.yahoo.com',
},
signal: AbortSignal.timeout(10000),
});
if (!response.ok) {
throw new Error(`HTTP error: ${response.status}`);
}
const data: YahooFinanceResponse = await response.json();
if (data.quoteResponse?.result && data.quoteResponse.result.length > 0) {
return data.quoteResponse.result[0];
}
return null;
} catch (error: any) {
console.error(`[YahooFinance] Error fetching quote for ${symbol}:`, error.message);
return null;
}
}
/**
* Validate if a symbol exists on Yahoo Finance
* @param symbol Stock symbol
* @param exchange Exchange to use
* @returns true if symbol exists
*/
export async function validateSymbol(
symbol: string,
exchange: 'NSE' | 'BSE' = 'NSE'
): Promise<boolean> {
try {
const quote = await getQuote(symbol, exchange);
return quote !== null && quote.regularMarketPrice !== undefined;
} catch {
return false;
}
}
