feat: check for ffmpeg + ffprobe version on startup

README.md

@@ -1,19 +1,26 @@
 # `ffmpegd`
-An FFmpeg server with a websocket API for [FFmpeg Commander](https://github.com/alfg/ffmpeg-commander).
-
-The goal is to provide a simple interface for sending FFmpeg jobs from the browser (and other supported clients in the future) while reporting realtime progress details.
+[FFmpeg](https://www.ffmpeg.org/) websocket server and API for [FFmpeg Commander](https://alfg.github.io/ffmpeg-commander).
 
 **Currently a work-in-progress! Bugs and breaking changes are expected.*
 
 ## How It Works
-TODO
+`ffmpegd` connects [FFmpeg Commander](https://alfg.github.io/ffmpeg-commander) to [ffmpeg](https://www.ffmpeg.org/) by providing a websocket server to send encode tasks and receive realtime progress updates back to the browser. This allows using `ffmpeg-commander` as a GUI for `ffmpeg`.
+
+The goal is to provide a simple interface for sending FFmpeg tasks from the browser (and other supported clients in the future) to your local machine.
+
+See [Usage](#Usage) for more details.
+
+```
+          process              websocket
+[ffmpeg] <-------> [ffmpegd] <-----------> [ffmpeg-commander]
+```
 
 ## Install
 ```
 $ go get -u github.com/alfg/ffmpegd
 ```
 
-Release binaries coming soon.
+Docker, Homebrew, and release binaries coming soon.
 
 ## Usage
 * [ffmpeg](https://www.ffmpeg.org/download.html) must be installed and available on your `$PATH`.
@@ -43,15 +50,19 @@ $ ffmpegd
 
 [ffmpegd] - websocket server for ffmpeg-commander.
 
-Server started on port :8080.
-Go to https://alfg.github.io/ffmpeg-commander to connect!
+  Checking FFmpeg version....4.3.1
+  Checking FFprobe version...4.3.1
+
+  Server started on port :8080.
+  - Go to https://alfg.github.io/ffmpeg-commander to connect!
+  - ffmpegd must be enabled in ffmpeg-commander options!
 
 Encoding... 6111 / 17620 (34.68%) 3.37x @ 80.77
 ```
 ![ffmpeg-commander](screenshot.png)
 
 ## API
-TODO
+TBD
 
 ## TODO
 * Support all `ffmpeg-comamnder` JSON options.

ffmpeg.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"io"
 	"os/exec"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -155,9 +156,15 @@ func (f *FFmpeg) Cancel() {
 }
 
 // Version gets the ffmpeg version.
-func (f *FFmpeg) Version() string {
-	out, _ := exec.Command(ffmpegCmd, "-version").Output()
-	return string(out)
+func (f *FFmpeg) Version() (string, error) {
+	out, err := exec.Command(ffmpegCmd, "-version").Output()
+	if err != nil {
+		return "", errors.New("ffmpeg not available on $PATH")
+	}
+	str := strings.Split(string(out), "\n")
+	r, _ := regexp.Compile(`(\d+(\.\d+){2})`)
+	version := r.FindString(str[0])
+	return version, nil
 }
 
 func (f *FFmpeg) updateProgress(stdout io.ReadCloser) {

ffprobe.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"os/exec"
+	"regexp"
 	"strings"
 )
 
@@ -38,6 +39,18 @@ func (f FFProbe) Run(input string) (*FFProbeResponse, error) {
 	return dat, nil
 }
 
+// Version gets the ffprobe version.
+func (f *FFProbe) Version() (string, error) {
+	out, err := exec.Command(ffprobeCmd, "-version").Output()
+	if err != nil {
+		return "", errors.New("ffprobe not available on $PATH")
+	}
+	str := strings.Split(string(out), "\n")
+	r, _ := regexp.Compile(`(\d+(\.\d+){2})`)
+	version := r.FindString(str[0])
+	return version, nil
+}
+
 // FFProbeResponse defines the response from ffprobe.
 type FFProbeResponse struct {
 	Streams []stream `json:"streams"`

main.go

@@ -38,6 +38,7 @@ var (
 			return true
 		},
 	}
+	progressCh chan struct{}
 )
 
 // Message payload from client.
@@ -56,12 +57,18 @@ type Status struct {
 	Err     string  `json:"err"`
 }
 
-var progressCh chan struct{}
-
 func main() {
 	// CLI Banner.
 	printBanner()
 
+	// Check if FFmpeg/FFprobe are available.
+	err := verifyFFmpeg()
+	if err != nil {
+		fmt.Println("\u001b[31m" + err.Error() + "\u001b[0m")
+		fmt.Println("\u001b[31mPlease ensure FFmpeg and FFprobe are installed and available on $PATH.\u001b[0m")
+		return
+	}
+
 	// HTTP/WS Server.
 	startServer()
 }
@@ -123,6 +130,23 @@ func handleMessages() {
 	}
 }
 
+func verifyFFmpeg() error {
+	ffmpeg := &FFmpeg{}
+	version, err := ffmpeg.Version()
+	if err != nil {
+		return err
+	}
+	fmt.Println("  Checking FFmpeg version....\u001b[32m" + version + "\u001b[0m")
+
+	ffprobe := &FFProbe{}
+	version, err = ffprobe.Version()
+	if err != nil {
+		return err
+	}
+	fmt.Println("  Checking FFprobe version...\u001b[32m" + version + "\u001b[0m\n")
+	return nil
+}
+
 func runEncode(input, output, payload string) {
 	probe := FFProbe{}
 	probeData, err := probe.Run(input)