add service readiness

Author: aptalca

Dockerfile

@@ -20,6 +20,7 @@ RUN \
     libatomic1 \
     nano \
     net-tools \
+    netcat \
     sudo && \
   echo "**** install code-server ****" && \
   if [ -z ${CODE_RELEASE+x} ]; then \

Dockerfile.aarch64

@@ -20,6 +20,7 @@ RUN \
     libatomic1 \
     nano \
     net-tools \
+    netcat \
     sudo && \
   echo "**** install code-server ****" && \
   if [ -z ${CODE_RELEASE+x} ]; then \

Dockerfile.armhf

@@ -20,6 +20,7 @@ RUN \
     libatomic1 \
     nano \
     net-tools \
+    netcat \
     sudo && \
   echo "**** install code-server ****" && \
   if [ -z ${CODE_RELEASE+x} ]; then \

root/etc/s6-overlay/s6-rc.d/svc-code-server/notification-fd

@@ -0,0 +1 @@
+3

root/etc/s6-overlay/s6-rc.d/svc-code-server/run

@@ -14,12 +14,13 @@ else
 fi
 
 exec \
-    s6-setuidgid abc \
-        /app/code-server/bin/code-server \
-            --bind-addr 0.0.0.0:8443 \
-            --user-data-dir /config/data \
-            --extensions-dir /config/extensions \
-            --disable-telemetry \
-            --auth "${AUTH}" \
-            "${PROXY_DOMAIN_ARG}" \
-            "${DEFAULT_WORKSPACE:-/config/workspace}"
+    s6-notifyoncheck -d -n 7 -w 1000 -c "nc -z 127.0.0.1 8443" \
+        s6-setuidgid abc \
+            /app/code-server/bin/code-server \
+                --bind-addr 0.0.0.0:8443 \
+                --user-data-dir /config/data \
+                --extensions-dir /config/extensions \
+                --disable-telemetry \
+                --auth "${AUTH}" \
+                "${PROXY_DOMAIN_ARG}" \
+                "${DEFAULT_WORKSPACE:-/config/workspace}"