From 7bbf733d98f21e76bfa2118983a3f6d080fa275b Mon Sep 17 00:00:00 2001
From: Maximilian Kalus <mk@eberl-online.com>
Date: Tue, 26 Nov 2019 13:27:20 +0100
Subject: [PATCH] Add /health endpoint for health checks. Can be enabled using
 --enable-health.

---
 README.md | 2 ++
 main.go   | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/README.md b/README.md
index ad9a112..8d47120 100644
--- a/README.md
+++ b/README.md
@@ -48,6 +48,8 @@ Usage of /goStatic:
         Define the user (default "gopher")
   -enable-basic-auth
         Enable basic auth. By default, password are randomly generated. Use --set-basic-auth to set it.
+  -enable-health
+        Enable health check endpoint. You can call /health to get a 200 response. Useful for Kubernetes, OpenFaas, etc.
   -fallback string
         Default fallback file. Either absolute for a specific asset (/index.html), or relative to recursively resolve (index.html).
   -password-length int
diff --git a/main.go b/main.go
index 2c4698c..11a9a66 100644
--- a/main.go
+++ b/main.go
@@ -5,6 +5,7 @@ package main
 
 import (
 	"flag"
+	"fmt"
 	"log"
 	"net/http"
 	"strconv"
@@ -19,6 +20,7 @@ var (
 	fallbackPath             = flag.String("fallback", "", "Default fallback file. Either absolute for a specific asset (/index.html), or relative to recursively resolve (index.html)")
 	headerFlag               = flag.String("append-header", "", "HTTP response header, specified as `HeaderName:Value` that should be added to all responses.")
 	basicAuth                = flag.Bool("enable-basic-auth", false, "Enable basic auth. By default, password are randomly generated. Use --set-basic-auth to set it.")
+	healthCheck              = flag.Bool("enable-health", false, "Enable health check endpoint. You can call /health to get a 200 response. Useful for Kubernetes, OpenFaas, etc.")
 	setBasicAuth             = flag.String("set-basic-auth", "", "Define the basic auth. Form must be user:password")
 	defaultUsernameBasicAuth = flag.String("default-user-basic-auth", "gopher", "Define the user")
 	sizeRandom               = flag.Int("password-length", 16, "Size of the randomized password")
@@ -90,6 +92,12 @@ func main() {
 		}
 	}
 
+	if *healthCheck {
+		http.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
+			fmt.Fprintf(w, "Ok")
+		})
+	}
+
 	http.Handle(pathPrefix, handler)
 
 	log.Printf("Listening at 0.0.0.0%v %v...", port, pathPrefix)