support for custom --config dir

cmd-options.go

@@ -31,6 +31,12 @@ var commands = []cli.Command{}
 var flags = []cli.Flag{}
 
 var (
+	configFlag = cli.StringFlag{
+		Name:  "config, C",
+		Value: mustGetMcConfigDir(),
+		Usage: "Path to configuration directory",
+	}
+
 	quietFlag = cli.BoolFlag{
 		Name:  "quiet, q",
 		Usage: "Suppress chatty console output",

cmd_test.go

@@ -32,26 +32,31 @@ import (
 	"github.com/minio/mc/pkg/quick"
 )
 
+var customConfigDir string
+
 func Test(t *testing.T) { TestingT(t) }
 
 type CmdTestSuite struct{}
 
 var _ = Suite(&CmdTestSuite{})
 
-func mustGetMcConfigDir() string {
-	dir, _ := getMcConfigDir()
-	return dir
-}
-
 var server *httptest.Server
 
 func (s *CmdTestSuite) SetUpSuite(c *C) {
 	// do not set it elsewhere, leads to data races since this is a global flag
 	globalQuietFlag = true
 
-	configDir, err := ioutil.TempDir(os.TempDir(), "cmd-")
+	tmpDir, err := ioutil.TempDir(os.TempDir(), "cmd-")
 	c.Assert(err, IsNil)
-	customConfigDir = configDir
+
+	// For windows the path is slightly different.
+	if runtime.GOOS == "windows" {
+		customConfigDir = filepath.Join(tmpDir, mcConfigWindowsDir)
+
+	} else {
+		customConfigDir = filepath.Join(tmpDir, mcConfigDir)
+	}
+	setMcConfigDir(customConfigDir)
 
 	_, err = doConfig("generate", nil)
 	c.Assert(err, IsNil)
@@ -158,9 +163,9 @@ func (s *CmdTestSuite) TestGetMcConfigDir(c *C) {
 	case "freebsd":
 		fallthrough
 	case "darwin":
-		c.Assert(dir, Equals, filepath.Join(customConfigDir, mcConfigDir))
+		c.Assert(dir, Equals, customConfigDir)
 	case "windows":
-		c.Assert(dir, Equals, filepath.Join(customConfigDir, mcConfigWindowsDir))
+		c.Assert(dir, Equals, customConfigDir)
 	default:
 		c.Fail()
 	}

config.go

@@ -23,6 +23,7 @@ import (
 	"runtime"
 	"sync"
 
+	"github.com/minio/mc/pkg/console"
 	"github.com/minio/mc/pkg/quick"
 	"github.com/minio/minio/pkg/iodine"
 )
@@ -36,20 +37,20 @@ type configV1 struct {
 // cached variables should *NEVER* be accessed directly from outside this file.
 var cache sync.Pool
 
-// customConfigDir used internally only by test functions
-var customConfigDir string
+// customConfigDir contains the whole path to config dir. Only access via get/set functions.
+var mcCustomConfigDir string
 
-// getMcConfigDir - construct minio client config folder
+// setMcConfigDir - construct minio client config folder.
+func setMcConfigDir(configDir string) {
+	mcCustomConfigDir = configDir
+}
+
+// getMcConfigDir - construct minio client config folder.
 func getMcConfigDir() (string, error) {
-	if customConfigDir != "" {
-		// For windows the path is slightly different
-		switch runtime.GOOS {
-		case "windows":
-			return filepath.Join(customConfigDir, mcConfigWindowsDir), nil
-		default:
-			return filepath.Join(customConfigDir, mcConfigDir), nil
-		}
+	if mcCustomConfigDir != "" {
+		return mcCustomConfigDir, nil
 	}
+
 	u, err := user.Current()
 	if err != nil {
 		return "", iodine.New(err, nil)
@@ -63,6 +64,15 @@ func getMcConfigDir() (string, error) {
 	}
 }
 
+// mustGetMcConfigDir - construct minio client config folder or fail
+func mustGetMcConfigDir() (configDir string) {
+	configDir, err := getMcConfigDir()
+	if err != nil {
+		console.Fatalf("Unable to determine default configuration folder. %s\n", err)
+	}
+	return configDir
+}
+
 // createMcConfigDir - create minio client config folder
 func createMcConfigDir() error {
 	p, err := getMcConfigDir()

globals.go

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-// This package contains all the global variables and constants
+// This package contains all the global variables and constants. ONLY TO BE ACCESSED VIA GET/SET FUNCTIONS.
 package main
 
 var (
@@ -26,7 +26,7 @@ var (
 	mcCurrentConfigVersion = "1.0.0"
 )
 
-// mc configuration related constants
+// mc configuration related constants.
 const (
 	mcConfigDir        = ".mc/"
 	mcConfigWindowsDir = "mc\\"

main.go

@@ -103,11 +103,12 @@ func main() {
 	registerCmd(updateCmd)  // update Check for new software updates
 
 	// register all the flags
-	registerFlag(quietFlag) // suppress console output
-	registerFlag(aliasFlag) // OS toolchain mimic
-	registerFlag(themeFlag) // console theme flag
-	registerFlag(jsonFlag)  // json formatted output
-	registerFlag(debugFlag) // enable debugging output
+	registerFlag(configFlag) // path to config folder
+	registerFlag(quietFlag)  // suppress console output
+	registerFlag(aliasFlag)  // OS toolchain mimic
+	registerFlag(themeFlag)  // console theme flag
+	registerFlag(jsonFlag)   // json formatted output
+	registerFlag(debugFlag)  // enable debugging output
 
 	app := cli.NewApp()
 	app.Usage = "Minio Client for object storage and filesystems"
@@ -117,6 +118,10 @@ func main() {
 	app.Flags = flags
 	app.Author = "Minio.io"
 	app.Before = func(ctx *cli.Context) error {
+		if ctx.GlobalString("config") != "" {
+			setMcConfigDir(ctx.GlobalString("config"))
+		}
+
 		globalQuietFlag = ctx.GlobalBool("quiet")
 		globalAliasFlag = ctx.GlobalBool("alias")
 		globalDebugFlag = ctx.GlobalBool("debug")