Allow child one-to-many instances to be updated without providing PK

[tsonobe1]

The following problems occurred when posting nested json data.
(Using `drf-writable-nested')

• If the parent's pk is not included in the child's json data, an error ("This field is required.") occurs.

code is bellow

Worries

class Worry(models.Model):
    goal = models.ForeignKey(
        Goal, on_delete=models.CASCADE, related_name='worries')
    worry_id = models.AutoField(primary_key=True)
    worry = models.TextField(verbose_name='心配事', null=True, blank=True)
    created_at = models.DateTimeField(
        verbose_name='作成日時', default=timezone.now)

    def __str__(self):
        return self.worry or ''


class Idea(models.Model):
    worry = models.ForeignKey(
        Worry, on_delete=models.CASCADE, related_name='ideas')
    idea_id = models.AutoField(primary_key=True)
    idea = models.TextField(verbose_name='対策', null=True, blank=True)
    created_at = models.DateTimeField(
        verbose_name='作成日時', default=timezone.now)

    def __str__(self):
        return self.idea or ''



class IdeaSerializer(serializers.ModelSerializer):
    class Meta:
        model = Idea
        fields = ['idea_id', 'idea', 'created_at', 'worry']



class WorrySerializer(WritableNestedModelSerializer):
    ideas = IdeaSerializer(many=True, required=False, allow_null=True)

    class Meta:
        model = Worry
        fields = ['worry_id', 'worry', 'created_at', 'goal', 'ideas']

endpoint for post

• http://127.0.0.1:8000/api/v1/goals/545b498e-93fd-4956-85c7-5bd292704dcd/worries/

payload

{
    "worry": "postman test",
    "goal": "545b498e-93fd-4956-85c7-5bd292704dcd",
    "ideas": [
        {
            "idea": "post man test"
        }
    ]
}

result

"worry": [
        "この項目は必須です。"
    ]

Hurdles

class Hurdle(models.Model):
    task = models.ForeignKey(
        Task, on_delete=models.CASCADE, related_name='hurdles')
    hurdle_id = models.AutoField(primary_key=True)
    hurdle = models.TextField(verbose_name='障害', null=True, blank=True)
    created_at = models.DateTimeField(
        verbose_name='作成日時', default=timezone.now)

    def __str__(self):
        return self.hurdle or ''


class Solution(models.Model):
    hurdle = models.ForeignKey(
        Hurdle, on_delete=models.CASCADE, related_name='solutions')
    solution_id = models.AutoField(primary_key=True)
    solution = models.TextField(verbose_name='解決策', null=True, blank=True)
    created_at = models.DateTimeField(
        verbose_name='作成日時', default=timezone.now)

    def __str__(self):
        return self.solution or ''


class SolutionSerializer(serializers.ModelSerializer):
    class Meta:
        model = Solution
        fields = ['solution_id', 'solution', 'created_at', 'hurdle']
        extra_kwargs = {
            # This was key!
            "hurdle":{"required": False}
        }


class HurdleSerializer(WritableNestedModelSerializer):
    solutions = SolutionSerializer(many=True, required=False, allow_null=True)

    class Meta:
        model = Hurdle
        fields = ['hurdle_id', 'hurdle', 'created_at', 'task', 'solutions']

endpoint for post

• http://127.0.0.1:8000/api/v1/goals/545b498e-93fd-4956-85c7-5bd292704dcd/tasks/5/hurdles/

payload

{
    "hurdle": "post man test",
    "task": 5,
    "solutions": [
        {
            "solution": "post man test"
        }
    ]
}

result

"hurdle": [
        "この項目は必須です。"
    ]

[tsonobe1]

Solution

beda-software/drf-writable-nested#29
beda-software/drf-writable-nested#29 (comment)

• add the required=False

Imported

Worry

class IdeaSerializer(serializers.ModelSerializer):
    class Meta:
        model = Idea
        fields = ['idea_id', 'idea', 'created_at', 'worry']
        extra_kwargs = {
            # This was key!
            "worry":{"required": False}
        }

Hurdle

class SolutionSerializer(serializers.ModelSerializer):
    class Meta:
        model = Solution
        fields = ['solution_id', 'solution', 'created_at', 'hurdle']
        extra_kwargs = {
            # This was key!
            "hurdle":{"required": False}
        }

Post

Worry

post

{
    "worry": "postman test",
    "goal": "545b498e-93fd-4956-85c7-5bd292704dcd",
    "ideas": [
        {
            "idea": "post man test"
        }
    ]
}

result

{
    "worry_id": 68,
    "worry": "postman test",
    "created_at": "2020-09-04T07:53:50.508206+09:00",
    "goal": "545b498e-93fd-4956-85c7-5bd292704dcd",
    "ideas": [
        {
            "idea_id": 127,
            "idea": "post man test",
            "created_at": "2020-09-04T07:53:50.520737+09:00",
            "worry": 68
        }
    ]
}

hurdle

post

{
    "hurdle": "post man test",
    "task": 5,
    "solutions": [
        {
            "solution": "post man test"
        }
    ]
}

###result

{
    "hurdle_id": 5,
    "hurdle": "post man test",
    "created_at": "2020-09-03T07:40:49.153273+09:00",
    "task": 5,
    "solutions": [
        {
            "solution_id": 18,
            "solution": "post man test",
            "created_at": "2020-09-03T07:40:49.169833+09:00",
            "hurdle": 5
        }
    ]
}

OK!