How to auth in SignalR wih token in Dart? - dart

Question

How to get access token in SignalR package?
I get access token doing POST request and after that I get the access token. I have a model where I have parsed JSON and have token field.
Auth authFromJson(String str) => Auth.fromJson(json.decode(str));
String authToJson(Auth data) => json.encode(data.toJson());
class Auth {
Auth({
this.token,
this.user,
});
final String? token;
final User? user;
POST request to API to get accesss token which I got succesfully:
Future<Auth> getToken() async {
String _email = "admin";
String _password = "admin";
Map<String, String> headers = {
'Content-Type': 'application/json',
'accept': ' */*'
};
final body = {
'username': _email,
'password': _password,
};
var response = await http.post(
Uri.parse("http://******/login"),
headers: headers,
body: jsonEncode(body),
);
print(response.body);
print(response.statusCode);
var jsonResponse = jsonDecode(response.body);
return Auth.fromJson(jsonResponse);
}
What I have in print in my console:
"token":"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHRwOi8vc2NoZW1hcy54bWxzb2FwLm9yZy93cy8yMDA1LzA","user":{}}
After all this stuff I opened docs and found out how SignalR package handle token auth and did the same thing:
Future<List> fetchLists() async {
final httpConnectionOptions = HttpConnectionOptions(
accessTokenFactory: () => getToken().then((value) => value.token ?? ''),
);
final hubConnection = HubConnectionBuilder()
.withUrl('http://*****/hub',
options: httpConnectionOptions)
.build();
await hubConnection.start();
So after all of this I got this error [ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: 302: Found
it means what I should add access token to each of requests and I do, but still get this error. How can i solve it or may be there is anoher way to add token in HubConnectionBuild?

Answer 1

There is parameter in accessTokenFactory which accept a function and have return type String so make a function which return token .
below attached code for your reference-
_hubConnection = HubConnectionBuilder()
.withUrl(chaturl,
options: HttpConnectionOptions(
headers: defaultHeaders,
accessTokenFactory: () async => await getToken() //define a function which return token
))
withAutomaticReconnect(retryDelays: [
20000,
]
).build();
//get token method
Future<dynamic> getToken() async {
SharedPreferences sharedPreferences = await SharedPreferences.getInstance();
if (sharedPreferences.containsKey("token")) {
print(sharedPreferences.getString("token"));
return sharedPreferences.getString("token");
} else {
return null;
}
}