custom bind address

.link-checker-service.toml

@@ -3,6 +3,9 @@
 
 # proxy = "http://<some-proxy>:<port>"
 
+# uncomment to bind to a custom address
+# bindAddress = "127.0.0.1:8080"
+
 # uncomment if CORS is undesired
 corsOrigins = [
     "http://localhost:8080",

CHANGES.md

@@ -2,7 +2,12 @@
 
 Notable changes will be documented here
 
-## 0.9.10 preliminary
+## 0.9.11
+
+- link-checker-service:
+  - `serve -a <addr>` allows customizing the bind address, e.g. localhost-only: `127.0.0.1:8080`
+
+## 0.9.10
 
 - binaries: link-checker-service, sample UI, sample large list check
 - link-checker-service:

README.md

@@ -143,11 +143,12 @@ For up-to-date help, check `link-checker-service help` or `link-checker-service
 
 To override the service port, define the `PORT` environment variable.
 
+To bind to another address, configure the `bindAddress` option, i.e.: `... serve -a 127.0.0.1:8080`
+
 ### Config File
 
 A sample configuration file [configuration file](.link-checker-service.toml) is available, with most possible configuration options listed.
 
-
 Start the app with the path to the configuration file: `--config <path-to-config-toml>`.
 
 ### Environment Variables

cmd/serve.go

@@ -19,6 +19,8 @@ var maxURLsInRequest uint = 0
 var disableRequestLogging = false
 var domainBlacklistGlobs []string
 
+const bindAddressKey = "bindAddress"
+
 var serveCmd = &cobra.Command{
 	Use:   "serve",
 	Short: "Starts the link checker web server",
@@ -31,6 +33,7 @@ var serveCmd = &cobra.Command{
 			MaxURLsInRequest:      maxURLsInRequest,
 			DisableRequestLogging: disableRequestLogging,
 			DomainBlacklistGlobs:  domainBlacklistGlobs,
+			BindAddress:           viper.GetString(bindAddressKey),
 		})
 		server.Run()
 	},
@@ -62,6 +65,10 @@ func init() {
 	flags.StringSliceVarP(&corsOrigins, "corsOrigins", "o", nil,
 		"provide a list of CORS origins to enable CORS headers, e.g. '-o http://localhost:8080 -o http://localhost:8090")
 
+	flags.StringP(bindAddressKey, "a", "",
+		"bind to a different address other than `:8080`, i.e. 0.0.0.0:4444 or 127.0.0.1:4444")
+	_ = viper.BindPFlag(bindAddressKey, flags.Lookup(bindAddressKey))
+
 	flags.StringVar(&IPRateLimit, "IPRateLimit", "", "rate-limit requests from an IP. e.g. 5-S (5 per second), 1000-H (1000 per hour)")
 
 	serveCmd.PersistentFlags().BoolVarP(&disableRequestLogging, "disableRequestLogging", "s", false, "disable request logging")

server/server.go

@@ -36,6 +36,7 @@ type Options struct {
 	MaxURLsInRequest      uint
 	DisableRequestLogging bool
 	DomainBlacklistGlobs  []string
+	BindAddress           string
 }
 
 // Server starts an instance of the link checker service
@@ -98,8 +99,15 @@ func (s *Server) Detail() *gin.Engine {
 // Run starts the service instance (binds a port)
 // set the PORT environment variable for a different port to bind at
 func (s *Server) Run() {
-	// listen and serve on 0.0.0.0:8080
-	if err := s.server.Run(); err != nil {
+	var err error
+	if s.options.BindAddress!="" {
+		// custom bind address, e.g. 0.0.0.0:4444
+		err = s.server.Run(s.options.BindAddress)
+	} else {
+		// default behavior: listen and serve on 0.0.0.0:${PORT:-8080}
+		err = s.server.Run()
+	}
+	if err != nil {
 		log.Fatalf("Could not start the server: %v", err)
 	}
 }