Don't bother fetching quotes if the market is closed

lib/format.go

@@ -47,6 +47,9 @@ func (self *Formatter) format_market(m *Market) string {
 	markup += "\n"
 	markup += `{{.Advances.name}}: {{.Advances.nyse}} ({{.Advances.nysep}}) on NYSE and {{.Advances.nasdaq}} ({{.Advances.nasdaqp}}) on Nasdaq. `
 	markup += `{{.Declines.name}}: {{.Declines.nyse}} ({{.Declines.nysep}}) on NYSE and {{.Declines.nasdaq}} ({{.Declines.nasdaqp}}) on Nasdaq`
+	if !m.Open {
+		markup += `<right>U.S. markets closed</right>`
+	}
 	markup += "\n"
 	markup += `New highs: {{.Highs.nyse}} on NYSE and {{.Highs.nasdaq}} on Nasdaq. `
 	markup += `New lows: {{.Lows.nyse}} on NYSE and {{.Lows.nasdaq}} on Nasdaq.`

lib/line_editor.go

@@ -147,17 +147,17 @@ func (self *LineEditor) execute() {
 	case '+':
 		tickers := self.tokenize()
 		if len(tickers) > 0 {
-			self.quotes.profile.AddTickers(tickers)
-			self.screen.Draw(self.quotes)
+			if added,_ := self.quotes.AddTickers(tickers); added > 0 {
+				self.screen.Draw(self.quotes)
+			}
 		}
 	case '-':
 		tickers := self.tokenize()
 		if len(tickers) > 0 {
 			before := len(self.quotes.profile.Tickers)
-			self.quotes.profile.RemoveTickers(tickers)
-			after := len(self.quotes.profile.Tickers)
-			if after < before {
+			if removed,_ := self.quotes.RemoveTickers(tickers); removed > 0 {
 				self.screen.Draw(self.quotes)
+				after := before - removed
 				for i := before; i > after; i-- {
 					self.screen.ClearLine(0, i + 4)
 				}

lib/profile.go

@@ -52,7 +52,8 @@ func (self *Profile) ListOfTickers() string {
 }
 
 //-----------------------------------------------------------------------------
-func (self *Profile) AddTickers(tickers []string) {
+func (self *Profile) AddTickers(tickers []string) (added int, err error) {
+	added = 0
 	existing := make(map[string]bool)
 
 	for _, ticker := range self.Tickers {
@@ -62,22 +63,27 @@ func (self *Profile) AddTickers(tickers []string) {
 	for _, ticker := range tickers {
 		if _, found := existing[ticker]; !found {
 			self.Tickers = append(self.Tickers, ticker)
+			added++
 		}
 	}
 	sort.Strings(self.Tickers)
-	self.Save()
+	err = self.Save()
+	return
 }
 
 //-----------------------------------------------------------------------------
-func (self *Profile) RemoveTickers(tickers []string) {
+func (self *Profile) RemoveTickers(tickers []string) (removed int, err error) {
+	removed = 0
 	for _, ticker := range tickers {
 		for i, existing := range self.Tickers {
 			if ticker == existing { // Requested ticker is there: remove i-th slice item.
 				self.Tickers = append(self.Tickers[:i], self.Tickers[i+1:]...)
+				removed++
 			}
 		}
 	}
-	self.Save()
+	err = self.Save()
+	return
 }
 
 // private

lib/yahoo_market.go

@@ -51,6 +51,7 @@ func (self *Market) Fetch() *Market {
 		panic(err)
 	}
 
+	body = self.check_if_market_open(body)
 	return self.extract(self.trim(body))
 }
 
@@ -59,6 +60,16 @@ func (self *Market) Format() string {
 	return new(Formatter).Format(self)
 }
 
+// private
+//-----------------------------------------------------------------------------
+func (self *Market) check_if_market_open(body []byte) []byte {
+	start := bytes.Index(body, []byte(`id="yfs_market_time"`))
+	finish := start + bytes.Index(body[start:], []byte(`</span>`))
+	self.Open = !bytes.Contains(body[start:finish], []byte(`closed`))
+
+	return body[finish:]
+}
+
 //-----------------------------------------------------------------------------
 func (self *Market) trim(body []byte) []byte {
 	start := bytes.Index(body, []byte(`<table id="yfimktsumm"`))

lib/yahoo_quotes.go

@@ -72,22 +72,25 @@ func (self *Quotes) Initialize(market *Market, profile *Profile) *Quotes {
 
 //-----------------------------------------------------------------------------
 func (self *Quotes) Fetch() *Quotes {
-
-	// Format the URL and send the request.
-	url := fmt.Sprintf(yahoo_quotes_url, self.profile.ListOfTickers())
-	response, err := http.Get(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)
+	if self.market.Open || self.stocks == nil {
+		// Format the URL and send the request.
+		url := fmt.Sprintf(yahoo_quotes_url, self.profile.ListOfTickers())
+		response, err := http.Get(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)
+		}
+
+		self.parse(self.sanitize(body))
 	}
 
-	return self.parse(self.sanitize(body))
+	return self
 }
 
 //-----------------------------------------------------------------------------
@@ -95,6 +98,22 @@ func (self *Quotes) Format() string {
 	return new(Formatter).Format(self)
 }
 
+//-----------------------------------------------------------------------------
+func (self *Quotes) AddTickers(tickers []string) (added int, err error) {
+	if added, err = self.profile.AddTickers(tickers); added > 0 {
+		self.stocks = nil	// Force fetch.
+	}
+	return
+}
+
+//-----------------------------------------------------------------------------
+func (self *Quotes) RemoveTickers(tickers []string) (removed int, err error) {
+	if removed, err = self.profile.RemoveTickers(tickers); removed > 0 {
+		self.stocks = nil	// Force fetch.
+	}
+	return
+}
+
 //-----------------------------------------------------------------------------
 func (self *Quotes) parse(body []byte) *Quotes {
 	lines := bytes.Split(body, []byte{'\n'})