go-chart/_examples/bar_chart_base_value/main.go
2018-12-06 16:46:27 +01:00

89 lines
1.8 KiB
Go

package main
import (
"fmt"
"log"
"net/http"
"os"
"git.gutmet.org/go-chart.git"
"git.gutmet.org/go-chart.git/drawing"
)
func drawChart(res http.ResponseWriter, req *http.Request) {
profitStyle := chart.Style{
Show: true,
FillColor: drawing.ColorFromHex("13c158"),
StrokeColor: drawing.ColorFromHex("13c158"),
StrokeWidth: 0,
}
lossStyle := chart.Style{
Show: true,
FillColor: drawing.ColorFromHex("c11313"),
StrokeColor: drawing.ColorFromHex("c11313"),
StrokeWidth: 0,
}
sbc := chart.BarChart{
Title: "Bar Chart Using BaseValue",
TitleStyle: chart.StyleShow(),
Background: chart.Style{
Padding: chart.Box{
Top: 40,
},
},
Height: 512,
BarWidth: 60,
XAxis: chart.Style{
Show: true,
},
YAxis: chart.YAxis{
Style: chart.Style{
Show: true,
},
Ticks: []chart.Tick{
{-4.0, "-4"},
{-2.0, "-2"},
{0, "0"},
{2.0, "2"},
{4.0, "4"},
{6.0, "6"},
{8.0, "8"},
{10.0, "10"},
{12.0, "12"},
},
},
UseBaseValue: true,
BaseValue: 0.0,
Bars: []chart.Value{
{Value: 10.0, Style: profitStyle, Label: "Profit"},
{Value: 12.0, Style: profitStyle, Label: "More Profit"},
{Value: 8.0, Style: profitStyle, Label: "Still Profit"},
{Value: -4.0, Style: lossStyle, Label: "Loss!"},
{Value: 3.0, Style: profitStyle, Label: "Phew Ok"},
{Value: -2.0, Style: lossStyle, Label: "Oh No!"},
},
}
res.Header().Set("Content-Type", "image/png")
err := sbc.Render(chart.PNG, res)
if err != nil {
fmt.Printf("Error rendering chart: %v\n", err)
}
}
func port() string {
if len(os.Getenv("PORT")) > 0 {
return os.Getenv("PORT")
}
return "8080"
}
func main() {
listenPort := fmt.Sprintf(":%s", port())
fmt.Printf("Listening on %s\n", listenPort)
http.HandleFunc("/", drawChart)
log.Fatal(http.ListenAndServe(listenPort, nil))
}