cli usage instructions

cmd/tegola/flags.go

@@ -2,31 +2,41 @@ package main
 
 import (
 	"flag"
+	"fmt"
+	"os"
 
 	"github.com/terranodo/tegola/server"
 )
 
 var (
-	configFile string
-	logFile    string
-	logFormat  string
-	port       string
+	configFile = *flag.String("config", "config.toml", "")
+	logFile    = *flag.String("log-file", "", "")
+	logFormat  = *flag.String("log-format", server.DefaultLogFormat, "")
+	port       = *flag.String("port", defaultHTTPPort, "")
 )
 
 const defaultHTTPPort = ":8080"
 
 func init() {
-	flag.StringVar(&configFile, "config", "config.toml", "Location of config file in TOML format. Can be absolute, relative or remote over http(s).")
-	flag.StringVar(&logFile, "log-file", "", "The file to log output to. Disable by default.")
-	flag.StringVar(&logFormat, "log-format", server.DefaultLogFormat,
-		`The format that the logger will log with.
-	
-	Available fields:
-		{{.Time}} : The current Date Time in RFC 2822 format.
-		{{.RequestIP}} : The IP address of the the requester.
-		{{.Z}} : The Zoom level.
-		{{.X}} : The X Coordinate.
-		{{.Y}} : The Y Coordinate.
-`)
-	flag.StringVar(&port, "port", defaultHTTPPort, "Webserver port to bind to")
+	flag.Usage = func() {
+		fmt.Fprintf(os.Stderr, `tegola %v <http://tegola.io>
+MVT tile server with support for PostGIS
+
+USAGE:	tegola [OPTIONS]
+
+OPTIONS:
+  -h, --help                Print usage
+  -v, --version             Print version and quit
+      --config      string  Location of config file in TOML format. Can be local or remote over http(s) (default config.toml)
+      --port        string  Port to bind HTTP server to (example :8080)
+      --log-file    string  The file to write request logs to (default disabled)
+      --log-format  string  The format the logger will log with. Available fields:
+                                {{.Time}} : The current Date Time in RFC 2822 format
+                                {{.RequestIP}} : The IP address of the the requester
+                                {{.Z}} : The Zoom level
+                                {{.X}} : The X Coordinate
+                                {{.Y}} : The Y Coordinate
+  
+`, Version)
+	}
 }