fix: read error message when get a 500 error

cwb/cwb.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 )
@@ -147,8 +146,8 @@ func checkResponse(r *http.Response) error {
 
 	errorResponse := &ErrorResponse{Response: r, Message: "unknown"}
 	switch r.StatusCode {
-	case http.StatusUnauthorized, http.StatusNotFound:
-		data, err := ioutil.ReadAll(r.Body)
+	case http.StatusUnauthorized, http.StatusNotFound, http.StatusInternalServerError:
+		data, err := io.ReadAll(r.Body)
 		if err != nil {
 			errorResponse.Message = fmt.Sprintf("reading body, %s", err.Error())
 		} else {
@@ -160,7 +159,7 @@ func checkResponse(r *http.Response) error {
 
 // decodeResponse decodes the API response.
 func decodeResponse(body io.Reader, to interface{}) error {
-	data, err := ioutil.ReadAll(body)
+	data, err := io.ReadAll(body)
 	if err != nil {
 		return err
 	}

cwb/cwb_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
@@ -96,7 +97,7 @@ func TestClient_NewRequest(t *testing.T) {
 		t.Errorf("NewRequest(%q) URL is %v, want %v", inURL, got, want)
 	}
 
-	body, _ := ioutil.ReadAll(req.Body)
+	body, _ := io.ReadAll(req.Body)
 	if got, want := string(body), outBody; got != want {
 		t.Errorf("NewRequest(%q) Body is %v, want %v", inBody, got, want)
 	}