fix osx bundle path for orderbooks.db

when running gdax-bookmap.app we now use ~/Library/Application Support/gdax-bookmap/orderbooks.db as boltdb file

README.md

@@ -14,6 +14,21 @@ cd $GOPATH/src/github.com/lian/gdax-bookmap
 ./script/build.sh
 ```
 
+## command flags
+```
+Usage of gdax-bookmap:
+  -base string
+        active BaseCurrency (default "BTC")
+  -db string
+        database file (default "orderbooks.db")
+  -h int
+        window height
+  -platforms string
+        active platforms (default "gdax-bitstamp-binance")
+  -w int
+        window width
+```
+
 ## current controls
 
 ```

main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"net/http"
+	"os"
 	"runtime"
 	"strings"
 	"time"
@@ -205,7 +206,8 @@ func main() {
 	var windowHeight int
 
 	fmt.Printf("Starting gdax-bookmap %s-%s\n", AppVersion, AppGitHash)
-	flag.StringVar(&ActivePlatform, "platforms", "gdax-bitstamp-binance-bitfinex", "active platforms")
+	//flag.StringVar(&ActivePlatform, "platforms", "gdax-bitstamp-binance-bitfinex", "active platforms")
+	flag.StringVar(&ActivePlatform, "platforms", "gdax-bitstamp-binance", "active platforms")
 	flag.StringVar(&ActiveBase, "base", "BTC", "active BaseCurrency")
 	flag.StringVar(&db_path, "db", "orderbooks.db", "database file")
 	flag.IntVar(&windowWidth, "w", 0, "window width")
@@ -214,7 +216,12 @@ func main() {
 
 	//runpprof()
 
-	db := util.OpenDB(db_path, []string{}, false)
+	db, err := util.OpenDB(db_path, []string{}, false)
+	if err != nil {
+		fmt.Println("OpenDB Error", err)
+		os.Exit(0)
+	}
+
 	infos = make([]*product_info.Info, 0)
 
 	if strings.Contains(strings.ToLower(ActivePlatform), "gdax") {

util/util.go

@@ -2,24 +2,35 @@ package util
 
 import (
 	"fmt"
-	"log"
+	"os"
+	"os/user"
+	"path/filepath"
 	"strconv"
 	"strings"
 
 	"github.com/boltdb/bolt"
 )
 
-func OpenDB(path string, buckets []string, readOnly bool) *bolt.DB {
+func OpenDB(path string, buckets []string, readOnly bool) (*bolt.DB, error) {
 	db, err := bolt.Open(path, 0600, &bolt.Options{ReadOnly: readOnly})
 	if err != nil {
-		log.Fatal(err)
+
+		path, err = osxBundlePath(path)
+		if err != nil {
+			return nil, err
+		}
+
+		db, err = bolt.Open(path, 0600, &bolt.Options{ReadOnly: readOnly})
+		if err != nil {
+			return nil, err
+		}
 	}
 
 	if len(buckets) > 0 {
 		CreateBucketsDB(db, buckets)
 	}
 
-	return db
+	return db, nil
 }
 
 func CreateBucketsDB(db *bolt.DB, buckets []string) {
@@ -34,6 +45,27 @@ func CreateBucketsDB(db *bolt.DB, buckets []string) {
 	})
 }
 
+func osxBundlePath(db_path string) (string, error) {
+	usr, err := user.Current()
+	if err != nil {
+		return "", err
+	}
+
+	path := filepath.Join(usr.HomeDir, "Library/Application Support")
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return "", err
+	}
+
+	path = filepath.Join(path, "gdax-bookmap")
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		if err = os.MkdirAll(path, 0755); err != nil {
+			return "", err
+		}
+	}
+
+	return filepath.Join(path, db_path), nil
+}
+
 func NumDecPlaces(v float64) int {
 	s := strconv.FormatFloat(v, 'f', -1, 64)
 	i := strings.IndexByte(s, '.')