Update config.DefaultParams to return slice of strings instead of string

pkg/config/config.go

@@ -1,6 +1,7 @@
 package config
 
 import (
+	"strings"
 	"sync"
 
 	"github.com/afex/hystrix-go/hystrix"
@@ -95,7 +96,7 @@ func ConcurrentOpacityCheckingEnabled() bool {
 	return getConfig().enableConcurrentOpacityChecking
 }
 
-// DefaultParams returns string of default parameters which will be applied to all image request, following the existing contract
-func DefaultParams() string {
-	return getConfig().defaultParams
+// DefaultParams returns []string of default parameters (separated by semicolon) which will be applied to all image request, following the existing contract
+func DefaultParams() []string {
+	return strings.Split(getConfig().defaultParams, ";")
 }

pkg/config/config_test.go

@@ -16,10 +16,6 @@ func TestConfigCasesWithStringValues(t *testing.T) {
 			key:      "log.level",
 			callFunc: LogLevel,
 		},
-		{
-			key:      "defaultParams",
-			callFunc: DefaultParams,
-		},
 	}
 
 	for _, c := range cases {
@@ -67,3 +63,22 @@ func TestConfigCasesWithIntValues(t *testing.T) {
 
 	assert.Equal(t, 0, v.GetInt("nonexistingkey"))
 }
+
+func TestConfigCasesWithStringSliceValues(t *testing.T) {
+	v := Viper()
+	v.Set("defaultParams", "auto=compress")
+	Update()
+	cases := []struct {
+		key      string
+		callFunc func() []string
+	}{
+		{
+			key:      "defaultParams",
+			callFunc: DefaultParams,
+		},
+	}
+
+	for _, c := range cases {
+		assert.Equal(t, v.GetStringSlice(c.key), c.callFunc())
+	}
+}