From 8ffa1d53e9c69db014fdd742d0779f0adfbc2b7e Mon Sep 17 00:00:00 2001
From: aler9 <46489434+aler9@users.noreply.github.com>
Date: Fri, 31 Jul 2020 18:12:42 +0200
Subject: [PATCH] add runOnInit

---
 README.md              | 27 +++++++--------------------
 conf.go                |  5 +++--
 main.go                | 21 +++++++++++++++++++++
 rtsp-simple-server.yml |  5 +++++
 4 files changed, 36 insertions(+), 22 deletions(-)

diff --git a/README.md b/README.md
index 71cbe3ff..3692bc62 100644
--- a/README.md
+++ b/README.md
@@ -87,26 +87,18 @@ paths:
     source: rtsp://original-url
 ```
 
-Start the server:
-```
-./rtsp-simple-server
-```
-
-Users can then connect to `rtsp://localhost:8554/proxied`, instead of connecting to the original url. The server supports any number of source streams, it's enough to add additional entries to the `paths` section.
+After starting the server, users can connect to `rtsp://localhost:8554/proxied`, instead of connecting to the original url. The server supports any number of source streams, it's enough to add additional entries to the `paths` section.
 
 #### Convert a webcam into a RTSP server
 
-Start the server:
-```
-./rtsp-simple-server
+Edit `rtsp-simple-server.yml` and replace everything inside section `paths` with the following content:
+```yaml
+paths:
+  webcam:
+    runOnInit: ffmpeg -f v4l2 -i /dev/video0 -f rtsp rtsp://localhost:8554/mystream
 ```
 
-Publish the webcam:
-```
-ffmpeg -f v4l2 -i /dev/video0 -f rtsp rtsp://localhost:8554/mystream
-```
-
-The last command works only on Linux; for Windows and Mac equivalents, read the [ffmpeg wiki](https://trac.ffmpeg.org/wiki/Capture/Webcam).
+After starting the server, the webcam can be opened with `rtsp://localhost:8554/webcam`. The ffmpeg command works only on Linux; for Windows and Mac equivalents, read the [ffmpeg wiki](https://trac.ffmpeg.org/wiki/Capture/Webcam).
 
 #### On-demand publishing
 
@@ -141,11 +133,6 @@ paths:
     publishPass: mypassword
 ```
 
-Start the server:
-```
-./rtsp-simple-server
-```
-
 Only publishers that provide both username and password will be able to proceed:
 ```
 ffmpeg -re -stream_loop -1 -i file.ts -c copy -f rtsp rtsp://admin:mypassword@localhost:8554/mystream
diff --git a/conf.go b/conf.go
index 870f7d8e..991706b5 100644
--- a/conf.go
+++ b/conf.go
@@ -18,6 +18,7 @@ type confPath struct {
 	SourceProtocol       string                   `yaml:"sourceProtocol"`
 	sourceProtocolParsed gortsplib.StreamProtocol ``
 	SourceOnDemand       bool                     `yaml:"sourceOnDemand"`
+	RunOnInit            string                   `yaml:"runOnInit"`
 	RunOnDemand          string                   `yaml:"runOnDemand"`
 	RunOnPublish         string                   `yaml:"runOnPublish"`
 	RunOnRead            string                   `yaml:"runOnRead"`
@@ -185,7 +186,7 @@ func loadConf(fpath string, stdin io.Reader) (*conf, error) {
 
 		if confp.Source != "record" {
 			if path == "all" {
-				return nil, fmt.Errorf("path 'all' cannot have a RTSP source")
+				return nil, fmt.Errorf("path 'all' cannot have a RTSP source; use another path")
 			}
 
 			if confp.SourceProtocol == "" {
@@ -260,7 +261,7 @@ func loadConf(fpath string, stdin io.Reader) (*conf, error) {
 		}
 
 		if confp.RunOnDemand != "" && path == "all" {
-			return nil, fmt.Errorf("option 'runOnDemand' cannot be used in path 'all'")
+			return nil, fmt.Errorf("path 'all' does not support option 'runOnDemand'; use another path")
 		}
 	}
 
diff --git a/main.go b/main.go
index b59fff2e..307a4007 100644
--- a/main.go
+++ b/main.go
@@ -8,6 +8,7 @@ import (
 	"net/http"
 	_ "net/http/pprof"
 	"os"
+	"os/exec"
 	"time"
 
 	"github.com/aler9/gortsplib"
@@ -176,6 +177,7 @@ type program struct {
 	sources        []*source
 	clients        map[*client]struct{}
 	paths          map[string]*path
+	cmds           []*exec.Cmd
 	publisherCount int
 	readerCount    int
 
@@ -263,6 +265,20 @@ func newProgram(args []string, stdin io.Reader) (*program, error) {
 		return nil, err
 	}
 
+	for _, confp := range conf.Paths {
+		if confp.RunOnInit != "" {
+			onInitCmd := exec.Command("/bin/sh", "-c", confp.RunOnInit)
+			onInitCmd.Stdout = os.Stdout
+			onInitCmd.Stderr = os.Stderr
+			err := onInitCmd.Start()
+			if err != nil {
+				p.log("ERR: %s", err)
+			}
+
+			p.cmds = append(p.cmds, onInitCmd)
+		}
+	}
+
 	if p.metrics != nil {
 		go p.metrics.run()
 	}
@@ -495,6 +511,11 @@ outer:
 		}
 	}()
 
+	for _, cmd := range p.cmds {
+		cmd.Process.Signal(os.Interrupt)
+		cmd.Wait()
+	}
+
 	for _, s := range p.sources {
 		s.events <- sourceEventTerminate{}
 		<-s.done
diff --git a/rtsp-simple-server.yml b/rtsp-simple-server.yml
index 74a3c971..67db2919 100644
--- a/rtsp-simple-server.yml
+++ b/rtsp-simple-server.yml
@@ -40,6 +40,11 @@ paths:
     # is connected, saving bandwidth
     sourceOnDemand: no
 
+    # command to run when this path is loaded by the program.
+    # this can be used, for example, to publish a stream and keep it always opened.
+    # This is terminated with SIGINT when the program closes.
+    runOnInit:
+
     # command to run when this path is requested.
     # This can be used, for example, to publish a stream on demand.
     # This is terminated with SIGINT when the path is not requested anymore.