mop/lib/yahoo_market.go

// Copyright (c) 2013 by Michael Dvorkin. All Rights Reserved.
//=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
package mop

import (
	"bytes"
	"io/ioutil"
	"net/http"
	"regexp"
	"strings"
)

type Market struct {
	Dow       map[string]string
	Nasdaq    map[string]string
	Sp500     map[string]string
	Advances  map[string]string
	Declines  map[string]string
	Unchanged map[string]string
	Highs     map[string]string
	Lows      map[string]string
}

const yahoo_market_url = `http://finance.yahoo.com/marketupdate/overview`

func GetMarket() Market {
	response, err := http.Get(yahoo_market_url)
	if err != nil {
		panic(err)
	}

	// Fetch response and get its body.
	defer response.Body.Close()
	body, err := ioutil.ReadAll(response.Body)
	if err != nil {
		panic(err)
	}

	return extract(trim(body))
}

func trim(body []byte) []byte {
	start := bytes.Index(body, []byte("<table id=\"yfimktsumm\""))
	finish := bytes.LastIndex(body, []byte("<table id=\"yfimktsumm\""))
	snippet := bytes.Replace(body[start:finish], []byte{'\n'}, []byte{}, -1)
	snippet = bytes.Replace(snippet, []byte("&amp;"), []byte{'&'}, -1)

	return snippet
}

func extract(snippet []byte) Market {
	const any = `\s*<.+?>`
	const some = `<.+?`
	const space = `\s*`
	const color = `#([08c]{6});">\s*`
	const price = `([\d\.,]+)`
	const percent = `\(([\d\.,%]+)\)`

	regex := []string{
		"(Dow)", any, price, some, color, price, some, percent, any,
		"(Nasdaq)", any, price, some, color, price, some, percent, any,
		"(S&P 500)", any, price, some, color, price, some, percent, any,
		"(Advances)", any, price, space, percent, any, price, space, percent, any,
		"(Declines)", any, price, space, percent, any, price, space, percent, any,
		"(Unchanged)", any, price, space, percent, any, price, space, percent, any,
		"(New Hi's)", any, price, any, price, any,
		"(New Lo's)", any, price, any, price, any,
	}

	re := regexp.MustCompile(strings.Join(regex, ""))
	matches := re.FindAllStringSubmatch(string(snippet), -1)

	// if len(matches) > 0 {
	//         fmt.Printf("%d matches\n", len(matches[0]))
	//         for i, str := range matches[0][1:] {
	//                 fmt.Printf("%d) [%s]\n", i, str)
	//         }
	// } else {
	//         println("No matches")
	// }

	m := Market{
		Dow:       make(map[string]string),
		Nasdaq:    make(map[string]string),
		Sp500:     make(map[string]string),
		Advances:  make(map[string]string),
		Declines:  make(map[string]string),
		Unchanged: make(map[string]string),
		Highs:     make(map[string]string),
		Lows:      make(map[string]string),
	}

	m.Dow[`name`] = matches[0][1]
	m.Dow[`latest`] = matches[0][2]
	m.Dow[`change`] = matches[0][4]
	switch matches[0][3] {
	case "008800":
		m.Dow[`change`] = "+" + matches[0][4]
		m.Dow[`percent`] = "+" + matches[0][5]
	case "cc0000":
		m.Dow[`change`] = "-" + matches[0][4]
		m.Dow[`percent`] = "-" + matches[0][5]
	default:
		m.Dow[`change`] = matches[0][4]
		m.Dow[`percent`] = matches[0][5]
	}

	m.Nasdaq[`name`] = matches[0][6]
	m.Nasdaq[`latest`] = matches[0][7]
	switch matches[0][8] {
	case "008800":
		m.Nasdaq[`change`] = "+" + matches[0][9]
		m.Nasdaq[`percent`] = "+" + matches[0][10]
	case "cc0000":
		m.Nasdaq[`change`] = "-" + matches[0][9]
		m.Nasdaq[`percent`] = "-" + matches[0][10]
	default:
		m.Nasdaq[`change`] = matches[0][9]
		m.Nasdaq[`percent`] = matches[0][10]
	}

	m.Sp500[`name`] = matches[0][11]
	m.Sp500[`latest`] = matches[0][12]
	switch matches[0][13] {
	case "008800":
		m.Sp500[`change`] = "+" + matches[0][14]
		m.Sp500[`percent`] = "+" + matches[0][15]
	case "cc0000":
		m.Sp500[`change`] = "-" + matches[0][14]
		m.Sp500[`percent`] = "-" + matches[0][15]
	default:
		m.Sp500[`change`] = matches[0][14]
		m.Sp500[`percent`] = matches[0][15]
	}

	m.Advances[`name`] = matches[0][16]
	m.Advances[`nyse`] = matches[0][17]
	m.Advances[`nysep`] = matches[0][18]
	m.Advances[`nasdaq`] = matches[0][19]
	m.Advances[`nasdaqp`] = matches[0][20]

	m.Declines[`name`] = matches[0][21]
	m.Declines[`nyse`] = matches[0][22]
	m.Declines[`nysep`] = matches[0][23]
	m.Declines[`nasdaq`] = matches[0][24]
	m.Declines[`nasdaqp`] = matches[0][25]

	m.Unchanged[`name`] = matches[0][26]
	m.Unchanged[`nyse`] = matches[0][27]
	m.Unchanged[`nysep`] = matches[0][28]
	m.Unchanged[`nasdaq`] = matches[0][29]
	m.Unchanged[`nasdaqp`] = matches[0][30]

	m.Highs[`name`] = matches[0][31]
	m.Highs[`nyse`] = matches[0][32]
	m.Highs[`nasdaq`] = matches[0][33]
	m.Lows[`name`] = matches[0][34]
	m.Lows[`nyse`] = matches[0][35]
	m.Lows[`nasdaq`] = matches[0][36]

	return m
}