Add health check command

.travis.yml

@@ -20,4 +20,4 @@ before_script:
 
 script:
   - ./hooks/build
-  - ./hooks/test
+  - ./hooks/travis_test

Dockerfile

@@ -27,4 +27,7 @@ VOLUME /app
 
 EXPOSE 6001
 
+HEALTHCHECK --interval=30s --timeout=5s \
+        CMD /usr/local/bin/health-check
+
 CMD ["start"]

bin/health-check

@@ -0,0 +1,40 @@
+#!/bin/sh
+set -x
+
+_init () {
+    scheme="http://"
+    address="$(netstat -nplt 2>/dev/null | awk ' /(.*\/laravel-echo-serv)/ { gsub(":::","127.0.0.1:",$4); print $4}')"
+    resource="/socket.io/socket.io.js"
+    start=$(stat -c "%Y" /proc/1)
+}
+
+fn_health_check () {
+    # In distributed environment like Swarm, traffic is routed
+    # to a container only when it reports a `healthy` status. So, we exit
+    # with 0 to ensure healthy status till distributed service starts (120s).
+    #
+    # Refer: https://github.com/moby/moby/pull/28938#issuecomment-301753272
+    if [[ $(( $(date +%s) - start )) -lt 120 ]]; then
+        exit 0
+    else
+        # Get the http response code
+        http_response=$(curl -s -k -o /dev/null -w "%{http_code}" ${scheme}${address}${resource})
+
+        # Get the http response body
+        http_response_body=$(curl -k -s ${scheme}${address}${resource})
+
+        # server returns response 403 and body "SSL required" if non-TLS
+        # connection is attempted on a TLS-configured server. Change
+        # the scheme and try again
+        if [[ "$http_response" = "403" ]] && \
+        [[ "$http_response_body" = "SSL required" ]]; then
+            scheme="https://"
+            http_response=$(curl -s -k -o /dev/null -w "%{http_code}" ${scheme}${address}${resource})
+        fi
+
+        # If http_response is 200 - server is up.
+        [[ "$http_response" = "200" ]]
+    fi
+}
+
+_init && fn_health_check

hooks/travis_test

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+IMAGE_NAME="oanhnn/laravel-echo-server:latest"
+LARAVEL_ECHO_SERVER_DB="redis"
+
+echo "=> Testing the image ${IMAGE_NAME}"
+docker run -d --net="host" \
+           -e REDIS_HOST=localhost \
+           -e LARAVEL_ECHO_SERVER_DB=${LARAVEL_ECHO_SERVER_DB} \
+           ${IMAGE_NAME}
+
+sleep 60
+docker ps
+
+curl --retry 10 --retry-delay 2 -I http://127.0.0.1:6001/socket.io/socket.io.js