use echo methods to return json

main.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"os"
@@ -18,6 +17,10 @@ var version = "dev"
 
 func main() {
 	app := &cli.App{
+		Commands: []*cli.Command{
+			{
+				Name:    "serve",
+				Aliases: []string{"c"},
 				Flags: []cli.Flag{
 					&cli.StringFlag{
 						Name:    "listen",
@@ -40,10 +43,6 @@ func main() {
 						Value:   ".",
 					},
 				},
-		Commands: []*cli.Command{
-			{
-				Name:    "serve",
-				Aliases: []string{"c"},
 				Usage: "complete a task on the list",
 				Action: func(ctx *cli.Context) error {
 					listen := ctx.String("listen")
@@ -77,6 +76,10 @@ type File struct {
 	Url  string `json:"url"`
 }
 
+type InternalError struct {
+	Error string `json:"error"`
+}
+
 func apiList(ctx echo.Context, directory, url string) error {
 	files := []File{}
 
@@ -98,11 +101,10 @@ func apiList(ctx echo.Context, directory, url string) error {
 
 		return nil
 	})
+
 	if err != nil {
-		return ctx.String(http.StatusInternalServerError, fmt.Sprintf("{\"error\":\"%s\"", err))
+		return ctx.JSON(http.StatusInternalServerError, InternalError{Error: fmt.Sprintf("%s", err)})
 	}
 
-	data, _ := json.MarshalIndent(files, "", "  ")
-
-	return ctx.String(http.StatusOK, string(data))
+	return ctx.JSON(http.StatusOK, files)
 }