snapshot

cmd/chart/main.go

@@ -0,0 +1,137 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"time"
+
+	chart "github.com/wcharczuk/go-chart"
+)
+
+var (
+	outputPath        = flag.String("output", "", "The output file")
+	disableLinreg     = flag.Bool("disable-linreg", false, "If we should omit linear regressions")
+	disableLastValues = flag.Bool("disable-last-values", false, "If we should omit last values")
+)
+
+// NewLogger returns a new logger.
+func NewLogger() *Logger {
+	return &Logger{
+		TimeFormat: time.RFC3339Nano,
+		Stdout:     os.Stdout,
+		Stderr:     os.Stderr,
+	}
+}
+
+// Logger is a basic logger.
+type Logger struct {
+	TimeFormat string
+	Stdout     io.Writer
+	Stderr     io.Writer
+}
+
+// Info writes an info message.
+func (l *Logger) Info(arguments ...interface{}) {
+	l.Println(append([]interface{}{"[INFO]"}, arguments...)...)
+}
+
+// Infof writes an info message.
+func (l *Logger) Infof(format string, arguments ...interface{}) {
+	l.Println(append([]interface{}{"[INFO]"}, fmt.Sprintf(format, arguments...))...)
+}
+
+// Debug writes an debug message.
+func (l *Logger) Debug(arguments ...interface{}) {
+	l.Println(append([]interface{}{"[DEBUG]"}, arguments...)...)
+}
+
+// Debugf writes an debug message.
+func (l *Logger) Debugf(format string, arguments ...interface{}) {
+	l.Println(append([]interface{}{"[DEBUG]"}, fmt.Sprintf(format, arguments...))...)
+}
+
+// Error writes an error message.
+func (l *Logger) Error(arguments ...interface{}) {
+	l.Println(append([]interface{}{"[ERROR]"}, arguments...)...)
+}
+
+// Errorf writes an error message.
+func (l *Logger) Errorf(format string, arguments ...interface{}) {
+	l.Println(append([]interface{}{"[ERROR]"}, fmt.Sprintf(format, arguments...))...)
+}
+
+// Err writes an error message.
+func (l *Logger) Err(err error) {
+	if err != nil {
+		l.Println(append([]interface{}{"[ERROR]"}, err.Error())...)
+	}
+}
+
+// FatalErr writes an error message and exits.
+func (l *Logger) FatalErr(err error) {
+	if err != nil {
+		l.Println(append([]interface{}{"[FATAL]"}, err.Error())...)
+		os.Exit(1)
+	}
+}
+
+// Println prints a new message.
+func (l *Logger) Println(arguments ...interface{}) {
+	fmt.Fprintln(l.Stdout, append([]interface{}{time.Now().UTC().Format(l.TimeFormat)}, arguments...)...)
+}
+
+// Errorln prints a new message.
+func (l *Logger) Errorln(arguments ...interface{}) {
+	fmt.Fprintln(l.Stderr, append([]interface{}{time.Now().UTC().Format(l.TimeFormat)}, arguments...)...)
+}
+
+func main() {
+	log := NewLogger()
+
+	rawData, err := ioutil.ReadAll(os.Stdin)
+	if err != nil {
+		log.FatalErr(err)
+	}
+
+	csvParts := chart.SplitCSV(string(rawData))
+
+	yvalues, err := chart.ParseFloats(csvParts...)
+
+	mainSeries := chart.ContinuousSeries{
+		Name:    "A test series",
+		XValues: chart.SeqRange(0, float64(len(csvParts))), //generates a []float64 from 1.0 to 100.0 in 1.0 step increments, or 100 elements.
+		YValues: yvalues,
+	}
+
+	linRegSeries := &chart.LinearRegressionSeries{
+		InnerSeries: mainSeries,
+	}
+
+	graph := chart.Chart{
+		Series: []chart.Series{
+			mainSeries,
+			linRegSeries,
+		},
+	}
+
+	var output *os.File
+	if *outputPath != "" {
+		output, err = os.Create(*outputPath)
+		if err != nil {
+			log.FatalErr(err)
+		}
+	} else {
+		output, err = ioutil.TempFile("", "*.png")
+		if err != nil {
+			log.FatalErr(err)
+		}
+	}
+
+	log.Info("rendering chart to", output.Name())
+	if err := graph.Render(chart.PNG, output); err != nil {
+		log.FatalErr(err)
+	}
+}