mostly working

cmd/chart/main.go

@@ -3,118 +3,78 @@ package main
 import (
 	"flag"
 	"fmt"
-	"io"
 	"io/ioutil"
 	"os"
-	"time"
+	"strings"
 
 	chart "github.com/wcharczuk/go-chart"
 )
 
 var (
 	outputPath        = flag.String("output", "", "The output file")
+	inputFormat       = flag.String("format", "csv", "The input format, either 'csv' or 'tsv' (defaults to 'csv')")
+	inputPath         = flag.String("f", "", "The input 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,
-	}
-}
+func main() {
+	flag.Parse()
+	log := chart.NewLogger()
 
-// 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())...)
+	var rawData []byte
+	var err error
+	if *inputPath != "" {
+		if *inputPath == "-" {
+			rawData, err = ioutil.ReadAll(os.Stdin)
+			if err != nil {
+				log.FatalErr(err)
+			}
+		} else {
+			rawData, err = ioutil.ReadFile(*inputPath)
+			if err != nil {
+				log.FatalErr(err)
+			}
+		}
+	} else if len(flag.Args()) > 0 {
+		rawData = []byte(flag.Args()[0])
+	} else {
+		flag.Usage()
 		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...)...)
-}
+	var parts []string
+	switch *inputFormat {
+	case "csv":
+		parts = chart.SplitCSV(string(rawData))
+	case "tsv":
+		parts = strings.Split(string(rawData), "\t")
+	default:
+		log.FatalErr(fmt.Errorf("invalid format; must be 'csv' or 'tsv'"))
+	}
 
-// 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)
+	yvalues, err := chart.ParseFloats(parts...)
 	if err != nil {
 		log.FatalErr(err)
 	}
 
-	csvParts := chart.SplitCSV(string(rawData))
-
-	yvalues, err := chart.ParseFloats(csvParts...)
-
+	var series []chart.Series
 	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.
+		Name:    "Values",
+		XValues: chart.LinearRange(1, float64(len(yvalues))),
 		YValues: yvalues,
 	}
+	series = append(series, mainSeries)
 
-	linRegSeries := &chart.LinearRegressionSeries{
-		InnerSeries: mainSeries,
+	if !*disableLinreg {
+		linRegSeries := &chart.LinearRegressionSeries{
+			InnerSeries: mainSeries,
+		}
+		series = append(series, linRegSeries)
 	}
 
 	graph := chart.Chart{
-		Series: []chart.Series{
-			mainSeries,
-			linRegSeries,
-		},
+		Series: series,
 	}
 
 	var output *os.File
@@ -130,8 +90,10 @@ func main() {
 		}
 	}
 
-	log.Info("rendering chart to", output.Name())
 	if err := graph.Render(chart.PNG, output); err != nil {
 		log.FatalErr(err)
 	}
+
+	fmt.Fprintln(os.Stdout, output.Name())
+	os.Exit(0)
 }