Implement --host, --port

README.md

@@ -36,7 +36,7 @@ Update to the latest version:
 
 ```bash
 gojekyll build       # builds the site in the current directory into _site
-gojekyll serve       # serve the app at http://localhost:8080
+gojekyll serve       # serve the app at http://localhost:4000
 gojekyll help
 gojekyll help build
 ```

cmd/gojekyll/helpers.go

@@ -1,17 +1,33 @@
 package main
 
 import (
+	"strconv"
+
 	kingpin "gopkg.in/alecthomas/kingpin.v2"
 )
 
 func boolVar(name string, ptr **bool) kingpin.Action {
 	return func(pc *kingpin.ParseContext) error {
 		value := lookupKingpinValue(name, pc)
-		option := false
-		if value != nil && *value == "true" {
-			option = true
+		if value != nil {
+			arg := *value == "true"
+			*ptr = &arg
+		}
+		return nil
+	}
+}
+
+func intVar(name string, ptr **int) kingpin.Action {
+	return func(pc *kingpin.ParseContext) error {
+		value := lookupKingpinValue(name, pc)
+		if value != nil {
+			n, err := strconv.Atoi(*value)
+			if err != nil {
+				panic(err)
+			}
+			arg := int(n)
+			*ptr = &arg
 		}
-		*ptr = &option
 		return nil
 	}
 }
@@ -20,8 +36,8 @@ func stringVar(name string, ptr **string) kingpin.Action {
 	return func(pc *kingpin.ParseContext) error {
 		value := lookupKingpinValue(name, pc)
 		if value != nil {
-			copy := *value
-			*ptr = &copy
+			arg := *value
+			*ptr = &arg
 		}
 		return nil
 	}

cmd/gojekyll/main.go

@@ -23,7 +23,7 @@ var (
 
 var (
 	app         = kingpin.New("gojekyll", "a (somewhat) Jekyll-compatible blog generator")
-	source      = app.Flag("source", "Source directory").Short('s').Default(".").String()
+	source      = app.Flag("source", "Source directory").Short('s').Default(".").ExistingDir()
 	_           = app.Flag("destination", "Destination directory").Short('d').Action(stringVar("destination", &configFlags.Destination)).String()
 	_           = app.Flag("drafts", "Render posts in the _drafts folder").Short('D').Action(boolVar("drafts", &configFlags.Drafts)).Bool()
 	_           = app.Flag("future", "Publishes posts with a future date").Action(boolVar("future", &configFlags.Future)).Bool()
@@ -43,6 +43,8 @@ var (
 
 	serve = app.Command("serve", "Serve your site locally").Alias("server").Alias("s")
 	open  = serve.Flag("open-url", "Launch your site in a browser").Short('o').Bool()
+	_     = app.Flag("host", "Host to bind to").Short('H').Action(stringVar("host", &configFlags.Host)).String()
+	_     = serve.Flag("port", "Port to listen on").Short('P').Action(intVar("port", &configFlags.Port)).Int()
 
 	variables    = app.Command("variables", "Display a file or URL path's variables").Alias("v").Alias("var").Alias("vars")
 	variablePath = variables.Arg("PATH", "Path, URL, site, or site...").String()

config/config.go

@@ -37,6 +37,8 @@ type Config struct {
 	ExcerptSeparator string `yaml:"excerpt_separator"`
 
 	// Serving
+	Host        string
+	Port        int
 	AbsoluteURL string `yaml:"url"`
 	BaseURL     string
 

config/default.go

@@ -47,6 +47,12 @@ plugins:   []
 # Conversion
 excerpt_separator: "\n\n"
 
+# Serving
+detach:  false
+port:    4000
+host:    127.0.0.1
+baseurl: "" # does not include hostname
+
 # Outputting
 permalink:     date
 paginate_path: /page:num

config/flags.go

@@ -3,10 +3,9 @@ package config
 // Flags are applied after the configuration file is loaded.
 // They are pointers to represent optional types, to tell whether they have been set.
 type Flags struct {
-	Destination *string
-	Unpublished *bool
-	Drafts      *bool
-	Future      *bool
+	Destination, Host           *string
+	Drafts, Future, Unpublished *bool
+	Port                        *int
 }
 
 // ApplyFlags overwrites the configuration with values from flags.
@@ -20,6 +19,12 @@ func (c *Config) ApplyFlags(flags Flags) {
 	if flags.Future != nil {
 		c.Future = *flags.Future
 	}
+	if flags.Host != nil {
+		c.Host = *flags.Host
+	}
+	if flags.Port != nil {
+		c.Port = *flags.Port
+	}
 	if flags.Unpublished != nil {
 		c.Unpublished = *flags.Unpublished
 	}

server/server.go

@@ -24,8 +24,9 @@ type Server struct {
 
 // Run runs the server.
 func (s *Server) Run(open bool, logger func(label, value string)) error {
+	cfg := s.Site.Config()
 	s.Site.SetAbsoluteURL("")
-	address := "localhost:4000"
+	address := fmt.Sprintf("%s:%d", cfg.Host, cfg.Port)
 	logger("Server address:", "http://"+address+"/")
 	if err := s.StartLiveReloader(); err != nil {
 		return err