How to send an image to an api in dart/flutter?
I saw other questions, but thats not what i want, i dont want to upload an image to a server, i dont want to convert to base64...
I only want to post a file in a form data or something else and get the returned info.
i have this, but has not work:
void onTakePictureButtonPressed() {
takePicture().then((String filePath) {
if (mounted) {
setState(() {
imagePath = filePath;
videoController?.dispose();
videoController = null;
});
http.post('http://ip:8082/composer/predict', headers: {
"Content-type": "multipart/form-data",
}, body: {
"image": filePath,
}).then((response) {
print("Response status: ${response.statusCode}");
print("Response body: ${response.body}");
});
if (filePath != null) showInSnackBar('Picture saved to $filePath');
}
});
}
Answer
The simplest method would be to post a multipart request like in this post and then post it to the server.
Make sure to import these in the beginning of the file:
import 'package:path/path.dart';
import 'package:async/async.dart';
import 'dart:io';
import 'package:http/http.dart' as http;
import 'dart:convert';
Add this class somewhere in your code:
upload(File imageFile) async {
// open a bytestream
var stream = new http.ByteStream(DelegatingStream.typed(imageFile.openRead()));
// get file length
var length = await imageFile.length();
// string to uri
var uri = Uri.parse("http://ip:8082/composer/predict");
// create multipart request
var request = new http.MultipartRequest("POST", uri);
// multipart that takes file
var multipartFile = new http.MultipartFile('file', stream, length,
filename: basename(imageFile.path));
// add file to multipart
request.files.add(multipartFile);
// send
var response = await request.send();
print(response.statusCode);
// listen for response
response.stream.transform(utf8.decoder).listen((value) {
print(value);
});
}
Then upload using:
upload(File(filePath));
In your code:
void onTakePictureButtonPressed() {
takePicture().then((String filePath) {
if (mounted) {
setState(() {
imagePath = filePath;
videoController?.dispose();
videoController = null;
});
// initiate file upload
Upload(File(filePath));
if (filePath != null) showInSnackBar('Picture saved to $filePath');
}
});
}