go-chart/testserver/main.go

package main

import (
	"bytes"
	"image/color"
	"log"
	"time"

	"github.com/wcharczuk/go-chart"
	"github.com/wcharczuk/go-web"
)

func main() {
	app := web.New()
	app.SetName("Chart Test Server")
	app.SetLogger(web.NewStandardOutputLogger())
	app.GET("/", func(rc *web.RequestContext) web.ControllerResult {
		rc.Response.Header().Set("Content-Type", "image/png")
		now := time.Now()
		c := chart.Chart{
			Title: "Stocks Bruh.",
			TitleStyle: chart.Style{
				Show: true,
			},
			Width:  1024,
			Height: 400,
			Canvas: chart.Style{
				Padding: chart.Box{
					Right:  40,
					Bottom: 40,
				},
			},
			Axes: chart.Style{
				Show:        true,
				StrokeWidth: 1.0,
			},
			YRange: chart.Range{
				Min: 0.0,
				Max: 7.0,
			},
			FinalValueLabel: chart.Style{
				Show: true,
			},
			Series: []chart.Series{
				chart.TimeSeries{
					Name: "goog",
					Style: chart.Style{
						StrokeWidth: 1.0,
					},
					XValues: []time.Time{now.AddDate(0, 0, -4), now.AddDate(0, 0, -3), now.AddDate(0, 0, -2), now.AddDate(0, 0, -1)},
					YValues: []float64{2.5, 5.0, 2.0, 3.0},
				},
				chart.TimeSeries{
					Name: "aapl",
					Style: chart.Style{
						StrokeWidth: 1.0,
						StrokeColor: color.RGBA{R: 0, G: 217, B: 116, A: 255},
					},
					XValues: []time.Time{now.AddDate(0, 0, -5), now.AddDate(0, 0, -4), now.AddDate(0, 0, -2), now.AddDate(0, 0, -1)},
					YValues: []float64{3.0, 2.7, 2.0, 1.1},
				},
			},
		}

		buffer := bytes.NewBuffer([]byte{})
		err := c.Render(chart.PNG, buffer)
		if err != nil {
			return rc.API().InternalError(err)
		}
		return rc.Raw(buffer.Bytes())
	})
	log.Fatal(app.Start())
}