Issue
I’m trying to upload an image to Strapi through Flutter Web. I’m aware (from this link) that I need to use FormData to do so. I’ve researched on many ways to do this and I stumble across Dio and of course Http.
Both solutions gave me errors:
Unsupported operation: MultipartFile is only supported where dart:io is available.
I’ve tried this code:
var request = new http.MultipartRequest("POST", Uri.parse(url));
request.files.add(
await http.MultipartFile.fromPath(
"files",
imageFilePath,
),
);
request.send().then((response) {
if (response.statusCode == 200) print("Uploaded!");
print(response.statusCode);
}).catchError((e) => print(e));
As suggested here.
And many other getting errors or Empty Data (400), when I use MultipartFile.fromBytes(...)
.
I’m just trying to upload a file, therefore I assume my body should only contain the FormData with as files
as it’s mentioned on Strapi’s Documentation.
Solution
So, I searched on the Flutter Discord for some help and I found out that my problem happens because Flutter Web can’t use 'dart:io'
, and using 'dart:html'
takes away the use of all of Flutter’s platforms.
I ended up using this imports:
import 'dart:convert';
import 'dart:typed_data';
import 'package:image_picker/image_picker.dart';
import 'package:http/http.dart' as http;
import 'package:http_parser/http_parser.dart';
import 'package:path/path.dart';
import 'package:async/async.dart';
and this is the function I created and worked:
Future<bool> uploadImage(
String imageFilePath,
Uint8List imageBytes,
) async {
String url = SERVERURL + "/uploadRoute";
PickedFile imageFile = PickedFile(imageFilePath);
var stream =
new http.ByteStream(DelegatingStream.typed(imageFile.openRead()));
var uri = Uri.parse(url);
int length = imageBytes.length;
var request = new http.MultipartRequest("POST", uri);
var multipartFile = new http.MultipartFile('files', stream, length,
filename: basename(imageFile.path),
contentType: MediaType('image', 'png'));
request.files.add(multipartFile);
var response = await request.send();
print(response.statusCode);
response.stream.transform(utf8.decoder).listen((value) {
print(value);
});
I had this issue using Strapi and this solution worked like a charm.
Answered By – Diego Cattarinich Clavel
Answer Checked By – Dawn Plyler (FlutterFixes Volunteer)