diff --git a/admin/config/extend.go b/admin/config/extend.go
index 2a7a9be..e78c286 100644
--- a/admin/config/extend.go
+++ b/admin/config/extend.go
@@ -10,14 +10,14 @@ var ExtConfig Extend
 //
 // 使用方法： config.ExtConfig......即可！！
 type Extend struct {
-	AMap   AMap   `yaml:"amap"`
-	Chorus Chorus `yaml:"chorus"`
+	AMap   AMap   `json:"amap" yaml:"amap"`
+	Chorus Chorus `json:"chorus" yaml:"chorus"`
 }
 
 type AMap struct {
-	Key string `yaml:"key"`
+	Key string `json:"key" yaml:"key"`
 }
 
 type Chorus struct {
-	StorageRoot string `yaml:"storage_root"`
+	StorageRoot string `json:"storage_root" yaml:"storage_root"`
 }
diff --git a/admin/config/extend_test.go b/admin/config/extend_test.go
new file mode 100644
index 0000000..b395de9
--- /dev/null
+++ b/admin/config/extend_test.go
@@ -0,0 +1,16 @@
+package config
+
+import (
+	"encoding/json"
+	"testing"
+)
+
+func TestExtendDecodesStorageRootFromGoAdminJSONReader(t *testing.T) {
+	var config Extend
+	if err := json.Unmarshal([]byte(`{"chorus":{"storage_root":"../var/storage"}}`), &config); err != nil {
+		t.Fatal(err)
+	}
+	if config.Chorus.StorageRoot != "../var/storage" {
+		t.Fatalf("storage root = %q", config.Chorus.StorageRoot)
+	}
+}
diff --git a/admin/config/settings.example.yml b/admin/config/settings.example.yml
index 799739d..44f6a32 100644
--- a/admin/config/settings.example.yml
+++ b/admin/config/settings.example.yml
@@ -24,4 +24,4 @@ settings:
   extend:
     chorus:
       # Read-only access to the same protected storage root used by Portal.
-        storage_root: ../var/storage
+      storage_root: ../var/storage