I want to to get the username of a user from another model, I have two tables(users and notes) in my database which are related to each other

but I'm getting this exception error

Exception has occurred.
FormatException (FormatException: Unexpected character (at character 1)
f1c84842-e146-4936-9659-e4872c012240
^
)

below is the json generated for both tables: users

[
    {
        "id": "f1c84842-e146-4936-9659-e4872c012240",
        "username": "admin",
        "password": "pbkdf2_sha256$320000$Zt8E5evRtqUS1GEdkFhj7l$3K0fL4oKonJJluJQaYC749RhjhwFOmv YGce0ajWuYY=",
        "email": "[email protected]"
    }
]

notes

[
    {
        "id": 1,
        "body": "debugging",
        "updated": "2022-07-24T03:39:57.188340Z",
        "created": "2022-07-24T03:39:57.188340Z",
        "user": "f1c84842-e146-4936-9659-e4872c012240"
    }
]

here is my model from the database

class CustomUser(AbstractUser):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    email = models.EmailField(unique=True)

class Note(models.Model):
    user = models.ForeignKey(CustomUser, null=True, on_delete=models.CASCADE)
    body = models.TextField()
    updated = models.DateTimeField(auto_now=True)
    created = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return self.body[0:50]

    class Meta:
        ordering = ['-updated']

below is my model class on flutter

List<Note> noteFromJson(String str) =>
    List<Note>.from(json.decode(str).map((x) => Note.fromJson(x)));

String noteToJson(List<Note> data) =>
    json.encode(List<dynamic>.from(data.map((x) => x.toJson())));

class Note {
  Note({
    this.id,
    required this.body,
    this.updated,
    this.created,
    required this.user,
  });

  int? id;
  String body;
  DateTime? updated;
  DateTime? created;
  User user;

  factory Note.fromJson(Map<String, dynamic> json) => Note(
        id: json["id"],
        body: json["body"] as String,
        updated: DateTime.parse(json["updated"]),
        created: DateTime.parse(json["created"]),
        user: User.fromJson(jsonDecode(json["user"])),
        
      );

  Map<String, dynamic> toJson() => {
        "id": id,
        "body": body,
        "updated": updated?.toIso8601String(),
        "created": created?.toIso8601String(),
        "user": user.toJson()
      };
}

List<User> userFromJson(String str) =>
    List<User>.from(json.decode(str).map((x) => User.fromJson(x)));

String userToJson(List<User> data) =>
    json.encode(List<dynamic>.from(data.map((x) => x.toJson())));


class User {
  User({
    required this.id,
    required this.username,
    this.password,
    required this.email,
  });

  String id;
  String username;
  String? password;
  String email;

  factory User.fromJson(Map<String, dynamic> json) => User(
        id: json["id"],
        username: json["username"],
        password: json["password"],
        email: json["email"],
      );

  Map<String, dynamic> toJson() => {
        "id": id,
        "username": username,
        "password": password,
        "email": email,
      };
}

and here is how i am parsing the json:

Client client = http.Client();

class RemoteServices {
  Future<List<Note>?> getNotes() async {
    var client = http.Client();

    var response = await client.get(retrieveUrl);

    //if data is retrieved
    if (response.statusCode == 200) {
      var json = response.body;
      final note = noteFromJson(json);
      return note;
    }
  }
}


List<Note>? notes;

  bool isLoaded = false;

  @override
  void initState() {
    getData();
    super.initState();
  }

  getData() async {
    notes = await RemoteServices().getNotes();
    print(notes);

    if (notes != null) {
      print(notes);
      setState(() {
        print(notes);
        isLoaded = true;
      });
    }
  }

update:

the below is response.body

Restarted application in 4,768ms.
I/flutter (12188): [{"id":1,"body":"debugging","updated":"2022-07-24T03:39:57.188340Z","created":"2022-07-24T03:39:57.188340Z","user":"f1c84842-e146-4936-9659-e4872c012240"}]

New update:

my views

class UserList(generics.ListCreateAPIView):
    queryset = User.objects.all()
    serializer_class = UserSerializer

class NoteList(generics.ListCreateAPIView):
    queryset = Note.objects.all()
    serializer_class = NoteSerializer

serializers

class NoteSerializer(ModelSerializer):
    class Meta:
        model = Note
        fields = '__all__'


class UserSerializer(ModelSerializer):
    class Meta:
        model = User
        fields = ['username', 'password', 'email']

CodePudding user response：

replace

class NoteSerializer(ModelSerializer):
    class Meta:
       model = Note
       fields = '__all__'


class UserSerializer(ModelSerializer):
    class Meta:
        model = User
        fields = ['username', 'password', 'email']

to

class UserSerializer(ModelSerializer):
    class Meta:
        model = User
        fields = ['username', 'password', 'email']

class NoteSerializer(ModelSerializer):
    user = UserSerializer()
    class Meta:
       model = Note
       fields = '__all__'

and test