Replace --start-frame, --end-frame with --frames

README.md

@@ -59,12 +59,12 @@ Usage of sequence:
         Grafana API URL
   -dashboard string
         ID of the dashboard
-  -end-frame int
-        The last frame to render (default 2)
   -end-padding duration
         Duration to add to the end of the frame
   -frame-interval duration
         Time progression between frames, positive = forward, negative = backward (default 5m0s)
+  -frames string
+        The frames to render, pass a range and/or a set (e.g. 1-10,12,15) (default "1-2")
   -height int
         The height of the image (default 1080)
   -max-concurrency int
@@ -73,8 +73,6 @@ Usage of sequence:
         Directory to write rendered frames to (default "frames")
   -panel int
         ID of the panel, 0 = Entire dashboard
-  -start-frame int
-        The first frame to render (default 1)
   -start-padding duration
         Duration to add to the start of the frame
   -start-time int

cmd/grafana-image-renderer-cli/main.go

@@ -8,6 +8,8 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"strconv"
+	"strings"
 	"time"
 
 	"github.com/MacroPower/grafana-image-renderer-sdk-go/pkg/client"
@@ -51,8 +53,7 @@ func main() {
 		startTimeMs       int64
 
 		sequenceCommand = flag.NewFlagSet("sequence", flag.ExitOnError)
-		startFrame      = sequenceCommand.Int("start-frame", 1, "The first frame to render")
-		endFrame        = sequenceCommand.Int("end-frame", 2, "The last frame to render")
+		frames          = sequenceCommand.String("frames", "1-2", "The frames to render, pass a range and/or a set (e.g. 1-10,12,15)")
 		frameInterval   = sequenceCommand.Duration("frame-interval", 5*time.Minute, "Time progression between frames, positive = forward, negative = backward")
 		startPadding    = sequenceCommand.Duration("start-padding", 0, "Duration to add to the start of the frame")
 		endPadding      = sequenceCommand.Duration("end-padding", 0, "Duration to add to the end of the frame")
@@ -114,12 +115,8 @@ func main() {
 			fmt.Println("max-concurrency must be at least 1")
 			argErr = true
 		}
-		if *startFrame < 1 {
-			fmt.Println("start-frame must be 1 or higher")
-			argErr = true
-		}
-		if *startFrame > *endFrame {
-			fmt.Println("end-frame must be after start-frame")
+		if *frames == "" {
+			fmt.Println("frames is required")
 			argErr = true
 		}
 	}
@@ -155,6 +152,38 @@ func main() {
 	}
 
 	if sequenceCommand.Parsed() {
+		var framesToRender []int
+		for _, framesGroup := range strings.Split(*frames, ",") {
+			if !strings.Contains(framesGroup, "-") {
+				f, err := strconv.Atoi(framesGroup)
+				if err != nil {
+					panic(err)
+				}
+				framesToRender = append(framesToRender, f)
+
+				continue
+			}
+
+			r := strings.Split(framesGroup, "-")
+
+			r1, err := strconv.Atoi(r[0])
+			if err != nil {
+				panic(err)
+			}
+
+			r2, err := strconv.Atoi(r[1])
+			if err != nil {
+				panic(err)
+			}
+
+			f, err := sequencer.GetSequence(r1, r2)
+			if err != nil {
+				panic(err)
+			}
+
+			framesToRender = append(framesToRender, f...)
+		}
+
 		seq := sequencer.FrameSequencer{
 			Renderer:       rf,
 			Start:          startTime,
@@ -168,7 +197,7 @@ func main() {
 				return ioutil.WriteFile(filename, b, 0644)
 			},
 		}
-		seq.Sequence(*startFrame, *endFrame)
+		seq.Sequence(framesToRender...)
 	}
 
 	fmt.Printf("Completed all work in %f seconds", time.Since(started).Seconds())

pkg/sequencer/sequencer.go

@@ -1,6 +1,7 @@
 package sequencer
 
 import (
+	"errors"
 	"fmt"
 	"time"
 )
@@ -17,7 +18,7 @@ type SaveFunc func([]byte, int) error
 
 // Sequencer defines and manages a render sequence.
 type Sequencer interface {
-	Sequence(int, int)
+	Sequence(...int)
 }
 
 type FrameSequencer struct {
@@ -50,12 +51,43 @@ type frame struct {
 	start, end time.Time
 }
 
-func (s *FrameSequencer) Sequence(start, end int) {
+func getFrame(n int, s *FrameSequencer) frame {
+	frameStart := s.Start.Add(s.Interval * time.Duration(n-1))
+	frameEnd := frameStart.Add(s.Interval)
+
+	if frameStart.After(frameEnd) {
+		// This allows users to inverse the frame order
+		// by passing a negative interval.
+		oldFrameEnd := frameEnd
+		frameEnd = frameStart
+		frameStart = oldFrameEnd
+	}
+
+	frameStart = frameStart.Add(s.StartPadding)
+	frameEnd = frameEnd.Add(s.EndPadding)
+
+	return frame{
+		num:   n,
+		start: frameStart,
+		end:   frameEnd,
+	}
+}
+
+func GetSequence(start, end int) ([]int, error) {
 	if start < 1 || start > end {
-		panic("malformed sequence")
+		return nil, errors.New("malformed sequence")
+	}
+
+	var seq []int
+	for i := start; i <= end; i++ {
+		seq = append(seq, i)
 	}
 
-	numFrames := 1 + end - start
+	return seq, nil
+}
+
+func (s *FrameSequencer) Sequence(frames ...int) {
+	numFrames := len(frames)
 	in := make(chan frame, numFrames)
 	out := make(chan error, numFrames)
 
@@ -67,22 +99,8 @@ func (s *FrameSequencer) Sequence(start, end int) {
 		go s.renderWorker(i, in, out)
 	}
 
-	for i := start; i <= end; i++ {
-		frameStart := s.Start.Add(s.Interval * time.Duration(i-1))
-		frameEnd := frameStart.Add(s.Interval)
-
-		if frameStart.After(frameEnd) {
-			// This allows users to inverse the frame order
-			// by passing a negative interval.
-			oldFrameEnd := frameEnd
-			frameEnd = frameStart
-			frameStart = oldFrameEnd
-		}
-
-		frameStart = frameStart.Add(s.StartPadding)
-		frameEnd = frameEnd.Add(s.EndPadding)
-
-		in <- frame{i, frameStart, frameEnd}
+	for _, i := range frames {
+		in <- getFrame(i, s)
 	}
 	close(in)