forward signals in restart wrapper (tilt-dev#586)

* Forward signals in restart wrapper Signed-off-by: Jared A. Scheel <[email protected]> * restart_process: Prevent race, add additional room to buffered channel * restart_process: update image Signed-off-by: Nick Santos <[email protected]> --------- Signed-off-by: Jared A. Scheel <[email protected]> Signed-off-by: Nick Santos <[email protected]> Co-authored-by: Jared A. Scheel <[email protected]> Co-authored-by: Travis Cline <[email protected]>
GEBIT · Jun 6, 2024 · e8cb91c · e8cb91c
1 parent 96da676
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diff --git a/restart_process/CONTRIBUTING.md b/restart_process/CONTRIBUTING.md
@@ -0,0 +1,7 @@
+# Contributing
+
+## Releasing
+
+If you have push access to the `tiltdev` repository on DockerHub, you can release a new version of the binaries used by this extension like so:
+1. run `release.sh` (builds `tilt-restart-wrapper` from source, builds and pushes a Docker image with the new binary and a fresh binary of `entr` also installed from source)
+2. update the image tag in the [Tiltfile](/restart_process/Tiltfile) with the tag you just pushed (you'll find the image referenced in the Dockerfile contents of the child image--look for "FROM tiltdev/restart-helper")
diff --git a/restart_process/README.md b/restart_process/README.md
@@ -173,11 +173,10 @@ When specified as a `command` in Kubernetes or Docker Compose YAML (this is how
 ```
 Any `args` specified in Kubernetes/Docker Compose are attached to the end of this call, and therefore in this case would apply TO THE `/bin/sh -c` CALL, rather than to the actual command run by `entr`; that is, any `args` specified by the user would be effectively ignored.
 
-In order to make `entr` usable without a shell, this extension uses [a simple binary](/restart_process/tilt-restart-wrapper.go) that invokes `entr` and writes to its stdin.
+In order to make `entr` usable without a shell, this extension uses [a simple binary](tilt-restart-wrapper.go) that invokes `entr` and writes to its stdin.
 
 Note: ideally `entr` could accept files-to-watch via flag instead of stdin, but (for a number of good reasons) this feature isn't likely to be added any time soon (see [entr#33](https://github.com/eradman/entr/issues/33)).
 
-## For Maintainers: Releasing
-If you have push access to the `tiltdev` repository on DockerHub, you can release a new version of the binaries used by this extension like so:
-1. run `release.sh` (builds `tilt-restart-wrapper` from source, builds and pushes a Docker image with the new binary and a fresh binary of `entr` also installed from source)
-2. update the image tag in the [Tiltfile](/restart_process/Tiltfile) with the tag you just pushed (you'll find the image referenced in the Dockerfile contents of the child image--look for "FROM tiltdev/restart-helper")
+## Contributing
+
+[Update instructions](CONTRIBUTING.md)
diff --git a/restart_process/Tiltfile b/restart_process/Tiltfile
@@ -45,7 +45,7 @@ def _helper(base_ref, ref, entrypoint, live_update, restart_file=RESTART_FILE, t
     # (which makes use of `entr` to watch files and restart processes) to the user's image
     # we also set the image's entrypoint to give k8s_custom_deploy a chance of working: https://github.com/tilt-dev/tilt-extensions/issues/391
     df = '''
-    FROM tiltdev/restart-helper:2021-11-03 as restart-helper
+    FROM tiltdev/restart-helper:2024-06-06 as restart-helper
 
     FROM {ref}
     RUN ["touch", "{file}"]

diff --git a/restart_process/test/Tiltfile b/restart_process/test/Tiltfile
@@ -1,5 +1,10 @@
 load('../Tiltfile', 'docker_build_with_restart')
 
-k8s_yaml('job.yaml')
+k8s_yaml('test-job.yaml')
+k8s_yaml('failing-job.yaml')
+
+docker_build_with_restart('test_job', '.', dockerfile='Dockerfile.test', entrypoint='/start.sh',
+                          live_update=[sync('./start.sh', '/start.sh')])
+
 docker_build_with_restart('failing_job', '.', dockerfile='Dockerfile.failing', entrypoint='/fail.sh',
                           live_update=[sync('./fail.sh', '/fail.sh')])
diff --git a/restart_process/test/custom.Tiltfile b/restart_process/test/custom.Tiltfile
@@ -1,9 +1,18 @@
 load('../Tiltfile', 'custom_build_with_restart')
 
-k8s_yaml('job.yaml')
+k8s_yaml('failing-job.yaml')
 custom_build_with_restart(
   'failing_job',
   command='docker build -t $EXPECTED_REF -f Dockerfile.failing .',
   deps=['fail.sh'],
   entrypoint='/fail.sh',
   live_update=[sync('./fail.sh', '/fail.sh')])
+
+
+k8s_yaml('test-job.yaml')
+custom_build_with_restart(
+  'test_job',
+  command='docker build -t $EXPECTED_REF -f Dockerfile.test .',
+  deps=['start.sh'],
+  entrypoint='/start.sh',
+  live_update=[sync('./start.sh', '/start.sh')])
diff --git a/restart_process/test/job.yaml → restart_process/test/failing-job.yaml b/restart_process/test/job.yaml → restart_process/test/failing-job.yaml
diff --git a/restart_process/test/start.sh b/restart_process/test/start.sh
@@ -4,6 +4,14 @@ RESTART_COUNT="$(cat restart_count.txt)"
 echo "RESTART_COUNT: $RESTART_COUNT"
 RESTART_COUNT=$((RESTART_COUNT+1))
 echo $RESTART_COUNT > restart_count.txt
+
+handle_sigterm() {
+  echo "SIGTERM received"
+  sleep 1
+}
+
+trap handle_sigterm SIGTERM
+
 while true
 do
   echo running

diff --git a/restart_process/test/test-job.yaml b/restart_process/test/test-job.yaml
@@ -0,0 +1,12 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: test-job
+spec:
+  template:
+    spec:
+      containers:
+        - name: test-job
+          image: test_job
+      restartPolicy: Never
+  backoffLimit: 4
diff --git a/restart_process/test/trigger_custom_deploy_live_update.sh b/restart_process/test/trigger_custom_deploy_live_update.sh
@@ -7,14 +7,15 @@ set -u
 
 touch start.sh
 # seconds
-TIMEOUT=5
+TIMEOUT=10
 for ((i=0;i<=$TIMEOUT;++i)) do
   tilt logs | grep -v test_update | grep -q "RESTART_COUNT: 1"
   if [[ $? -eq 0 ]]; then
     echo restart detected
     exit 0
   fi
   echo no restart detected
+  touch start.sh
   sleep 1
 done
 exit 1
diff --git a/restart_process/tilt-restart-wrapper.go b/restart_process/tilt-restart-wrapper.go
@@ -35,13 +35,15 @@ import (
 	"log"
 	"os"
 	"os/exec"
+	"os/signal"
 	"strings"
 	"syscall"
 )
 
 var watchFile = flag.String("watch_file", "/.restart-proc", "File that entr will watch for changes; changes to this file trigger `entr` to rerun the command(s) passed")
 var entrPath = flag.String("entr_path", "/entr", "Path to `entr` executable")
 var entrFlags = flag.String("entr_flags", "-rz", "Command line flags to pass to `entr` executable")
+var verboseSignals = flag.Bool("verbose_signals", false, "Print signals received by `tilt-restart-wrapper`")
 
 func main() {
 	flag.Parse()
@@ -52,7 +54,25 @@ func main() {
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
 
-	if err := cmd.Run(); err != nil {
+	if err := cmd.Start(); err != nil {
+		log.Fatalf("error starting command: %v", err)
+	}
+
+	// Set up a signal forwarding handler
+	sigs := make(chan os.Signal, 10)
+	signal.Notify(sigs)
+	go func() {
+		for sig := range sigs {
+			if *verboseSignals {
+				log.Printf("Received signal: %s (%d), forwarding to pid %d", sig, sig.(syscall.Signal), cmd.Process.Pid)
+			}
+			if err := cmd.Process.Signal(sig); err != nil {
+				log.Println("Error forwarding signal:", err)
+			}
+		}
+	}()
+
+	if err := cmd.Wait(); err != nil {
 		if exiterr, ok := err.(*exec.ExitError); ok {
 			// The program has exited with an exit code != 0
 			if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {