findata-go

A unified Go library for accessing financial markets data across multiple exchanges and countries.

Currently Supported:

• 🇮🇳 Indian equities (NSE)
• 🇮🇳 Indian mutual funds (AMFI)
• 💰 Precious metals (Gold, Silver, Platinum)
• 🪙 Cryptocurrencies (Bitcoin, Ethereum, Solana, and more)

Coming Soon:

• 🇺🇸 US equities (NYSE, NASDAQ)
• 🇮🇳 BSE stocks

Inspired by finance-go, this library provides a clean, exchange-agnostic API that automatically routes symbols to the appropriate data provider.

Features

✅ Exchange-Agnostic API - Just use symbols, library handles routing ✅ Auto-Detection - Automatically detects market from symbol pattern ✅ Configurable - Set default markets and override per-request ✅ Batch Fetching - Fetch multiple quotes efficiently ✅ Zero Dependencies - Only uses Go standard library ✅ Type-Safe - Comprehensive type definitions ✅ Well-Tested - Includes integration tests ✅ Structured Logging - Built-in logging with multiple levels and formats

Installation

Requirements: Go 1.22 or higher (1.24 recommended)

go get github.com/Vikramarjuna/findata-go

Quick Start

Equity Quotes (Exchange-Agnostic)

package main

import (
    "fmt"
    "log"

    "github.com/Vikramarjuna/findata-go/equity"
)

func main() {
    // Just use the symbol - library auto-detects the exchange!
    quote, err := equity.Get("RELIANCE")
    if err != nil {
        log.Fatal(err)
    }

    fmt.Printf("%s (%s): %s %.2f (%.2f%%)\n",
        quote.Symbol, quote.Exchange, quote.Currency,
        quote.LastPrice, quote.PChange)

    // Batch fetch multiple symbols
    symbols := []string{"TCS", "INFY", "WIPRO"}
    quotes, _ := equity.GetMultiple(symbols)

    for symbol, q := range quotes {
        fmt.Printf("%s: %s %.2f\n", symbol, q.Currency, q.LastPrice)
    }
}

Output:

RELIANCE (NSE): INR 1577.00 (-0.96%)
TCS: INR 3213.00
INFY: INR 1604.10
WIPRO: INR 263.00

Configuration & Options

import (
    "github.com/Vikramarjuna/findata-go/config"
    "github.com/Vikramarjuna/findata-go/equity"
)

func main() {
    // Set default market (optional - defaults to India)
    config.SetDefaultMarket(config.MarketIndia)

    // Now all symbols default to Indian market
    quote, _ := equity.Get("RELIANCE")  // Uses NSE

    // Override per-request with options
    quote, _ = equity.Get("RELIANCE",
        equity.WithExchange(config.ExchangeNSE))

    // Or specify market
    quote, _ = equity.Get("RELIANCE",
        equity.WithMarket(config.MarketIndia))

    // Custom HTTP client
    client := &http.Client{Timeout: 60 * time.Second}
    config.SetHTTPClient(client)
}

Mutual Fund NAVs

import "github.com/Vikramarjuna/findata-go/mf"

func main() {
    // Search for funds
    results, _ := mf.Search("HDFC Flexi Cap")
    for _, nav := range results {
        fmt.Printf("%s: ₹%.4f\n", nav.SchemeName, nav.NAV)
    }

    // Get by ISIN, scheme code, or name
    nav, _ := mf.Get("INF179K01997")
    fmt.Printf("NAV: ₹%.4f (as of %s)\n", nav.NAV, nav.Date)

    // Batch fetch
    navs, _ := mf.GetMultiple([]string{"119551", "119552"})
}

Metal Prices

import "github.com/Vikramarjuna/findata-go/metals"

func main() {
    // Get specific metal price
    goldPrice, _ := metals.Get(metals.Gold, "24K")
    fmt.Printf("Gold 24K: ₹%.2f per gram\n", goldPrice.PricePerGram)

    // Get all metal prices
    allPrices, _ := metals.GetAll()
    for _, price := range allPrices {
        fmt.Printf("%s %s: ₹%.2f per gram\n",
            price.Metal, price.Purity, price.PricePerGram)
    }

    // Supported metals and purities:
    // Gold: 24K, 22K, 18K, 14K
    // Silver: 999, 925
    // Platinum: 999, 950
}

Cryptocurrency Quotes

import "github.com/Vikramarjuna/findata-go/crypto"

func main() {
    // Get specific crypto quote in USD
    btcQuote, _ := crypto.Get("bitcoin")
    fmt.Printf("Bitcoin: $%.2f\n", btcQuote.CurrentPrice)
    fmt.Printf("24h Change: %.2f%%\n", btcQuote.PriceChangePct24h)

    // Get crypto quote in different currency
    ethQuote, _ := crypto.Get("ethereum", crypto.WithCurrency("INR"))
    fmt.Printf("Ethereum: ₹%.2f\n", ethQuote.CurrentPrice)

    // Get multiple crypto quotes
    coinIDs := []string{"bitcoin", "ethereum", "solana"}
    quotes, _ := crypto.GetMultiple(coinIDs)
    for coinID, quote := range quotes {
        fmt.Printf("%s: $%.2f\n", coinID, quote.CurrentPrice)
    }

    // Use CoinGecko coin IDs (e.g., "bitcoin", "ethereum", "solana", "cardano", etc.)
    // See https://www.coingecko.com/ for full list of supported coins
}

API Reference

Equity Package

The main package for fetching stock quotes across all supported exchanges.

Functions:

• equity.Get(symbol string, opts ...Option) (*Quote, error) - Fetch a single quote
• equity.GetMultiple(symbols []string, opts ...Option) (map[string]*Quote, []error) - Batch fetch

Options:

• equity.WithMarket(market config.Market) - Override default market
• equity.WithExchange(exchange config.Exchange) - Specify exact exchange

Quote Structure:

type Quote struct {
    Symbol        string
    Exchange      config.Exchange  // NSE, BSE, NYSE, NASDAQ
    CompanyName   string
    Industry      string
    Sector        string
    LastPrice     float64
    Currency      string           // INR, USD, etc.
    Change        float64
    PChange       float64
    PreviousClose float64
    Open          float64
    DayHigh       float64
    DayLow        float64
    YearHigh      float64
    YearLow       float64
    Volume        float64
    Value         float64
    Indices       []string
    Metadata      map[string]string
}

Config Package

Global configuration for the library.

Functions:

• config.SetDefaultMarket(market Market) - Set default market (India, US, Auto)
• config.GetDefaultMarket() Market - Get current default market
• config.SetHTTPClient(client *http.Client) - Set custom HTTP client
• config.SetAPIKey(provider, key string) - Set API key for providers
• config.SetUserAgent(ua string) - Set custom user agent

Constants:

// Markets
config.MarketIndia  // "IN"
config.MarketUS     // "US"
config.MarketAuto   // "AUTO"

// Exchanges
config.ExchangeNSE     // "NSE"
config.ExchangeBSE     // "BSE"
config.ExchangeNYSE    // "NYSE"
config.ExchangeNASDAQ  // "NASDAQ"

MF Package

Mutual fund NAV data from AMFI.

Functions:

• mf.GetAll() (map[string]*NAV, error) - Fetch all NAVs
• mf.Get(identifier string) (*NAV, error) - Get by code/ISIN/name
• mf.Search(query string) ([]*NAV, error) - Search by name
• mf.GetMultiple(identifiers []string) (map[string]*NAV, []error) - Batch fetch

NAV Structure:

type NAV struct {
    SchemeCode string
    ISIN       string  // Primary ISIN
    ISINReinv  string  // Reinvestment ISIN
    SchemeName string
    NAV        float64
    Date       string
}

Logging

The library provides optional structured logging using Go's standard log/slog package.

By default, logging is disabled (silent). This follows Go library best practices - the library won't pollute your logs unless you explicitly enable it.

Enable Logging

import "github.com/Vikramarjuna/findata-go/logger"

// Enable with default settings (INFO level, text format, stderr)
logger.SetLogger(logger.NewSlogLogger())

// Enable with custom configuration
logger.SetLogger(logger.NewSlogLogger(
    logger.WithLevel(logger.LevelDebug),      // DEBUG, INFO, WARN, ERROR
    logger.WithFormat(logger.FormatJSON),     // FormatText or FormatJSON
    logger.WithOutput(logFile),               // Any io.Writer
))

// Disable logging
logger.SetLogger(nil)

Example Output

time=2026-01-06T21:54:51.887+05:30 level=INFO msg="successfully fetched NSE quote" symbol=RELIANCE price=1577.00 currency=INR

Use Your Own Logger

Implement the logger.Logger interface to use your own logging framework:

type Logger interface {
    Debug(msg string, keysAndValues ...any)
    Info(msg string, keysAndValues ...any)
    Warn(msg string, keysAndValues ...any)
    Error(msg string, keysAndValues ...any)
}

logger.SetLogger(myCustomLogger)

See the logger package documentation for full API details.

Examples

See the examples directory for complete working examples.

Versioning

This project follows Semantic Versioning. See CHANGELOG.md for release history.

Contributing

Contributions are welcome! Please read CONTRIBUTING.md for details on:

• How to report bugs
• How to suggest features
• Development setup
• Coding standards
• Pull request process

License

MIT License - see LICENSE file for details.

Acknowledgments

• Inspired by finance-go
• Data sources: NSE India, AMFI India