Graphene-Django and many to many relationship lookup

Question

I have two Django models - Teacher and Student and have a many-to-many relationship. Teachers can have multiple students and students can have multiple teachers. There is 'through' model called 'Remarks' where a teacher can mark a student as favourite.

I am new to GraphQL. I am trying to implement two queries:
1. Teachers and all of their students
2. Teachers and their favourite students

I am having difficulty in implementing the second query and have been unable to do so.

models.py

SUBJECTS = (
    ("Maths", "Maths"),
    ("Chemistry", "Chemistry"),
    ("Physics", "Physics")
)

class Student(models.Model):
    name = models.CharField(max_length=100)
    age = models.IntegerField(default=0)

    def __str__(self):
        return self.name

class Teacher(models.Model):
    name = models.CharField(max_length=100)
    subject = models.CharField(max_length=100, choices=SUBJECTS)
    students = models.ManyToManyField(Student, through="Remarks")

    def __str__(self):
        return self.name

class Remarks(models.Model):
    student = models.ForeignKey(Student, related_name="student", on_delete=models.DO_NOTHING)
    teacher = models.ForeignKey(Teacher, related_name="teacher", on_delete=models.DO_NOTHING)
    favorite = models.BooleanField(default=False, choices=(
        (True, "Yes"),
        (False, "No")
    ))

schema.py

import graphene
from graphene import relay, ObjectType
from graphene_django import DjangoObjectType
from graphene_django.filter import DjangoFilterConnectionField
from .models import Teacher, Student, Remarks

class RemarkNode(DjangoObjectType):
    class Meta:
        model = Remarks
        filter_fields = ['favorite']
        interfaces = (relay.Node, )


class TeacherNode(DjangoObjectType):
    favorite = graphene.Field(RemarkNode)

    class Meta:
        model = Teacher
        filter_fields = ['name', 'subject']
        interfaces = (relay.Node, )


class StudentNode(DjangoObjectType):
    class Meta:
        model = Student
        filter_fields = {
            'name': ['exact', 'icontains', 'istartswith'],
            'age': ['exact'],            
            'favorite': ['exact']
        }
        interfaces = (relay.Node, )

class Query(graphene.ObjectType):
    teacher = relay.Node.Field(TeacherNode)
    all_teachers = DjangoFilterConnectionField(TeacherNode)

    student = relay.Node.Field(StudentNode)
    all_students = DjangoFilterConnectionField(StudentNode)

    def resolve_favorites(self, info, **kwargs):
        teacher = Teacher.objects.get(pk=self.id)
        remarks = Remarks.objects.filter(teacher=teacher)
        return [each.student for each in remarks]

Grewitz

Answer 1

schema.py

class TeacherNode(DjangoObjectType):
favorite = graphene.List(RemarkNode)

def resolve_favorite(self, info, **kwargs):
    remarks = Remarks.objects.filter(teacher=self.id)
    return remarks

class Meta:
    model = Teacher
    filter_fields = ['name', 'subject']
    interfaces = (relay.Node, )

class StudentNode(DjangoObjectType):
    class Meta:
        model = Student
        filter_fields = {
          'name': ['exact', 'icontains', 'istartswith'],
          'age': ['exact'],
        }
        interfaces = (relay.Node, )

class TeacherQuery(graphene.ObjectType):
    teacher = relay.Node.Field(TeacherNode)
    all_teachers = DjangoFilterConnectionField(TeacherNode)

    student = relay.Node.Field(StudentNode)
    all_students = DjangoFilterConnectionField(StudentNode)

Caboose

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