From a782fd188483433e436702a6dddee9d7373293f6 Mon Sep 17 00:00:00 2001
From: Lukasz Zajaczkowski <zreigz@gmail.com>
Date: Tue, 30 Jul 2024 08:48:20 +0200
Subject: [PATCH] chore: update WithFiles method (#54)

---
 uploadfiles.go | 112 ++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 110 insertions(+), 2 deletions(-)

diff --git a/uploadfiles.go b/uploadfiles.go
index 7b75da2..4b96a14 100644
--- a/uploadfiles.go
+++ b/uploadfiles.go
@@ -2,6 +2,7 @@ package gqlclient
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -9,7 +10,9 @@ import (
 	"net/http"
 
 	client "github.com/Yamashou/gqlgenc/clientv2"
+	"github.com/Yamashou/gqlgenc/graphqljson"
 	"github.com/schollz/progressbar/v3"
+	"github.com/vektah/gqlparser/v2/gqlerror"
 )
 
 // Upload File represents a file to upload.
@@ -19,8 +22,8 @@ type Upload struct {
 	R     io.Reader
 }
 
-func WithFiles(files []Upload) func(req *http.Request) {
-	return func(req *http.Request) {
+func WithFiles(files []Upload, httpClient *http.Client) func(ctx context.Context, req *http.Request, gqlInfo *client.GQLRequestInfo, res interface{}) error {
+	return func(ctx context.Context, req *http.Request, gqlInfo *client.GQLRequestInfo, res interface{}) error {
 		bd := client.Request{}
 		err := json.NewDecoder(req.Body).Decode(&bd)
 		if err != nil {
@@ -67,5 +70,110 @@ func WithFiles(files []Upload) func(req *http.Request) {
 		req.Body = &reader
 		req.Header.Set("Accept", "application/json; charset=utf-8")
 		req.Header.Set("Content-Type", bodyWriter.FormDataContentType())
+
+		resp, err := httpClient.Do(req)
+		if err != nil {
+			return fmt.Errorf("request failed: %w", err)
+		}
+		defer resp.Body.Close()
+
+		body, err := io.ReadAll(resp.Body)
+		if err != nil {
+			return fmt.Errorf("failed to read response body: %w", err)
+		}
+
+		return parseResponse(body, resp.StatusCode, res)
+	}
+}
+
+func parseResponse(body []byte, httpCode int, result interface{}) error {
+	errResponse := &ErrorResponse{}
+	isKOCode := httpCode < 200 || 299 < httpCode
+	if isKOCode {
+		errResponse.NetworkError = &HTTPError{
+			Code:    httpCode,
+			Message: fmt.Sprintf("Response body %s", string(body)),
+		}
+	}
+
+	// some servers return a graphql error with a non OK http code, try anyway to parse the body
+	if err := unmarshal(body, result); err != nil {
+		if gqlErr, ok := err.(*GqlErrorList); ok {
+			errResponse.GqlErrors = &gqlErr.Errors
+		} else if !isKOCode { // if is KO code there is already the http error, this error should not be returned
+			return err
+		}
+	}
+
+	if errResponse.HasErrors() {
+		return errResponse
+	}
+
+	return nil
+}
+
+// response is a GraphQL layer response from a handler.
+type response struct {
+	Data   json.RawMessage `json:"data"`
+	Errors json.RawMessage `json:"errors"`
+}
+
+func unmarshal(data []byte, res interface{}) error {
+	resp := response{}
+	if err := json.Unmarshal(data, &resp); err != nil {
+		return fmt.Errorf("failed to decode data %s: %w", string(data), err)
 	}
+
+	if resp.Errors != nil && len(resp.Errors) > 0 {
+		// try to parse standard graphql error
+		errors := &GqlErrorList{}
+		if e := json.Unmarshal(data, errors); e != nil {
+			return fmt.Errorf("faild to parse graphql errors. Response content %s - %w ", string(data), e)
+		}
+
+		return errors
+	}
+
+	if err := graphqljson.UnmarshalData(resp.Data, res); err != nil {
+		return fmt.Errorf("failed to decode data into response %s: %w", string(data), err)
+	}
+
+	return nil
+}
+
+// GqlErrorList is the struct of a standard graphql error response
+type GqlErrorList struct {
+	Errors gqlerror.List `json:"errors"`
+}
+
+func (e *GqlErrorList) Error() string {
+	return e.Errors.Error()
+}
+
+// HTTPError is the error when a GqlErrorList cannot be parsed
+type HTTPError struct {
+	Code    int    `json:"code"`
+	Message string `json:"message"`
+}
+
+// ErrorResponse represent an handled error
+type ErrorResponse struct {
+	// populated when http status code is not OK
+	NetworkError *HTTPError `json:"networkErrors"`
+	// populated when http status code is OK but the server returned at least one graphql error
+	GqlErrors *gqlerror.List `json:"graphqlErrors"`
+}
+
+// HasErrors returns true when at least one error is declared
+func (er *ErrorResponse) HasErrors() bool {
+	return er.NetworkError != nil || er.GqlErrors != nil
+}
+
+func (er *ErrorResponse) Error() string {
+	content, err := json.Marshal(er)
+	if err != nil {
+		return err.Error()
+	}
+
+	return string(content)
 }