Crypto Portfolio

package main

import (
	"fmt"
	"net/http"
	"log"
	"io/ioutil"
	"encoding/json"
	"strconv"
)

// what and quantity
// btc = 4.83
var holdings = map[string]float64{
	"bitcoin":  1.0001,
	"litecoin": 1,
	"stellar":  1,
	"monero":   1,
}

const initial = 1000.00

const baseAPI = "https://api.coinmarketcap.com/v1/ticker"

type Ticker struct {
	ID                string `json:"id"`
	Name              string `json:"name"`
	Symbol            string `json:"symbol"`
	PriceUSD          string `json:"price_usd"`
	PercentChanged1H  string `json:"percent_change_1h"`
	PercentChanged24H string `json:"percent_change_24h"`
	PercentChanged1D  string `json:"percent_change_7d"`
	CurrentValue      float64
}

type Resp []Ticker

func main() {
	var results []Ticker

	for k, v := range holdings {
		url := fmt.Sprintf("%s/%s", baseAPI, k)

		resp, err := http.Get(url)

		if err != nil {
			log.Println("err getting ticket", k)
			continue
		}

		bytes, err := ioutil.ReadAll(resp.Body)
		if err != nil {
			log.Println("err reading response", err, k)
			continue
		}

		var t Ticker
		var r Resp
		err = json.Unmarshal(bytes, &r)
		if err != nil {
			log.Println("err unmarshaling response", err, k)
		}

		if len(r) == 0 {
			log.Println("no results found", k)
			continue
		} else {
			t = r[0]
		}

		currentValue, err := strconv.ParseFloat(t.PriceUSD, 64)
		if err != nil {
			log.Println("err parsing price usd", err, k)
		}

		t.CurrentValue = currentValue * v
		results = append(results, t)
	}

	var total float64
	total = 0
	for _, v := range results {
		total += v.CurrentValue
		println(
			fmt.Sprintf("%8s", v.Name),
			fmt.Sprintf("% 16.8f", v.CurrentValue),
			fmt.Sprintf("% 16.8s", v.PriceUSD),
			fmt.Sprintf("% 8s", v.PercentChanged24H))
	}

	println("=========================")
	println(fmt.Sprintf("%8s", "Total"), fmt.Sprintf("% 16.8f", total))
	println(fmt.Sprintf("%8s", "Initial"), fmt.Sprintf("% 16.8f", initial))
	println("=========================")
	println(fmt.Sprintf("%8s", "Profit"), fmt.Sprintf("% 16.8f", total-initial))
}