feat(docker): test a container to check that it is still working (#346)

Dockerfile

@@ -10,4 +10,8 @@ LABEL maintainer="Bo-Yi Wu <appleboy.tw@gmail.com>"
 ADD release/linux/amd64/gorush /bin/
 
 EXPOSE 8088 9000
+
+HEALTHCHECK --start-period=2s --interval=10s --timeout=5s \
+  CMD ["/bin/gorush", "--ping"]
+
 ENTRYPOINT ["/bin/gorush"]

Dockerfile.alpine

@@ -13,4 +13,7 @@ RUN apk add --no-cache ca-certificates && \
 ADD release/linux/amd64/gorush /bin/
 
 EXPOSE 8088 9000
+HEALTHCHECK --start-period=2s --interval=10s --timeout=5s \
+  CMD ["/bin/gorush", "--ping"]
+
 ENTRYPOINT ["/bin/gorush"]

Dockerfile.arm

@@ -10,4 +10,7 @@ LABEL maintainer="Bo-Yi Wu <appleboy.tw@gmail.com>"
 ADD release/linux/arm/gorush /bin/
 
 EXPOSE 8088 9000
+HEALTHCHECK --start-period=2s --interval=10s --timeout=5s \
+  CMD ["/bin/gorush", "--ping"]
+
 ENTRYPOINT ["/bin/gorush"]

Dockerfile.arm64

@@ -10,4 +10,7 @@ LABEL maintainer="Bo-Yi Wu <appleboy.tw@gmail.com>"
 ADD release/linux/arm64/gorush /bin/
 
 EXPOSE 8088 9000
+HEALTHCHECK --start-period=2s --interval=10s --timeout=5s \
+  CMD ["/bin/gorush", "--ping"]
+
 ENTRYPOINT ["/bin/gorush"]

Dockerfile.i386

@@ -10,4 +10,7 @@ LABEL maintainer="Bo-Yi Wu <appleboy.tw@gmail.com>"
 ADD release/linux/i386/gorush /bin/
 
 EXPOSE 8088 9000
+HEALTHCHECK --start-period=2s --interval=10s --timeout=5s \
+  CMD ["/bin/gorush", "--ping"]
+
 ENTRYPOINT ["/bin/gorush"]

Dockerfile.windows

@@ -6,4 +6,7 @@ LABEL maintainer="Bo-Yi Wu <appleboy.tw@gmail.com>" \
   org.label-schema.schema-version="1.0"
 
 ADD release/gorush.exe /gorush.exe
+HEALTHCHECK --start-period=2s --interval=10s --timeout=5s \
+  CMD ["\\gorush.exe", "--ping"]
+
 ENTRYPOINT [ "\\gorush.exe" ]

main.go

@@ -4,6 +4,7 @@ import (
 	"flag"
 	"fmt"
 	"log"
+	"net/http"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -19,6 +20,7 @@ func main() {
 	opts := config.ConfYaml{}
 
 	var (
+		ping        bool
 		showVersion bool
 		configFile  string
 		topic       string
@@ -56,6 +58,7 @@ func main() {
 	flag.BoolVar(&opts.Ios.Production, "production", false, "production mode in iOS")
 	flag.StringVar(&topic, "topic", "", "apns topic in iOS")
 	flag.StringVar(&proxy, "proxy", "", "http proxy url")
+	flag.BoolVar(&ping, "ping", false, "ping server")
 
 	flag.Usage = usage
 	flag.Parse()
@@ -126,6 +129,13 @@ func main() {
 		}
 	}
 
+	if ping {
+		if err := pinger(); err != nil {
+			gorush.LogError.Warnf("ping server error: %v", err)
+		}
+		return
+	}
+
 	// send android notification
 	if opts.Android.Enabled {
 		gorush.PushConf.Android.Enabled = opts.Android.Enabled
@@ -270,6 +280,7 @@ Server Options:
     --proxy <proxy>                  Proxy URL (only for GCM)
     --pid <pid path>                 Process identifier path
     --redis-addr <redis addr>        Redis addr (default: localhost:6379)
+    --ping                           healthy check command for container
 iOS Options:
     -i, --key <file>                 certificate key file path
     -P, --password <password>        certificate key password
@@ -290,6 +301,20 @@ func usage() {
 	os.Exit(0)
 }
 
+// handles pinging the endpoint and returns an error if the
+// agent is in an unhealthy state.
+func pinger() error {
+	resp, err := http.Get("http://localhost:" + gorush.PushConf.Core.Port + gorush.PushConf.API.HealthURI)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != 200 {
+		return fmt.Errorf("server returned non-200 status code")
+	}
+	return nil
+}
+
 func createPIDFile() error {
 	if !gorush.PushConf.Core.PID.Enabled {
 		return nil