make function ReadDockerConfigFile more flexible

rename the variable

make parameter more flexible

handle docker config file path

use a single set of paths

delete debug print

gofmt

delete the empty line

comment is not correct

move the comment to the correct place

keep original signature

godoc

pkg/credentialprovider/config_test.go

@@ -18,10 +18,51 @@ package credentialprovider
 
 import (
 	"encoding/json"
+	"io/ioutil"
+	"os"
+	"path/filepath"
 	"reflect"
 	"testing"
 )
 
+func TestReadDockerConfigFile(t *testing.T) {
+	configJsonFileName := "config.json"
+	var fileInfo *os.File
+	preferredPaths := []string{}
+
+	//test dockerconfig json
+	inputDockerconfigJsonFile := "{ \"auths\": { \"http://foo.example.com\":{\"auth\":\"Zm9vOmJhcgo=\",\"email\":\"foo@example.com\"}}}"
+
+	preferredPath, err := ioutil.TempDir("", "test_foo_bar_dockerconfigjson_")
+	if err != nil {
+		t.Fatalf("Creating tmp dir fail: %v", err)
+		return
+	}
+	defer os.RemoveAll(preferredPath)
+	preferredPaths = append(preferredPaths, preferredPath)
+	absDockerConfigFileLocation, err := filepath.Abs(filepath.Join(preferredPath, configJsonFileName))
+	if err != nil {
+		t.Fatalf("While trying to canonicalize %s: %v", preferredPath, err)
+	}
+
+	if _, err := os.Stat(absDockerConfigFileLocation); os.IsNotExist(err) {
+		//create test cfg file
+		fileInfo, err = os.OpenFile(absDockerConfigFileLocation, os.O_CREATE|os.O_RDWR, 0664)
+		if err != nil {
+			t.Fatalf("While trying to create file %s: %v", absDockerConfigFileLocation, err)
+		}
+		defer fileInfo.Close()
+	}
+
+	fileInfo.WriteString(inputDockerconfigJsonFile)
+
+	orgPreferredPath := GetPreferredDockercfgPath()
+	SetPreferredDockercfgPath(preferredPath)
+	defer SetPreferredDockercfgPath(orgPreferredPath)
+	if _, err := ReadDockerConfigFile(); err != nil {
+		t.Errorf("Getting docker config file fail : %v preferredPath : %q", err, preferredPath)
+	}
+}
 func TestDockerConfigJsonJSONDecode(t *testing.T) {
 	input := []byte(`{"auths": {"http://foo.example.com":{"username": "foo", "password": "bar", "email": "foo@example.com"}, "http://bar.example.com":{"username": "bar", "password": "baz", "email": "bar@example.com"}}}`)