Flask Marshmallow

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1. Basic Serialization:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(required=True)
    email = ma.String(required=True)

user_schema = UserSchema()
user_dict = user_schema.dump(user)

2. Nested Serialization:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class OrderSchema(ma.Schema):
    items = ma.Nested(ItemSchema, many=True)

order_schema = OrderSchema()
order_dict = order_schema.dump(order)

3. Filtering by Schema:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(required=True)
    email = ma.String(required=True)

    class Meta:
        exclude = ('password',)

user_schema = UserSchema()
filtered_user_dict = user_schema.dump(user)

4. Complex Filtering by Schema:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(required=True)
    email = ma.String(required=True)

    class Meta:
        fields = ('id', 'name', 'email')
        additional = ('first_name', 'last_name')

user_schema = UserSchema()
filtered_user_dict = user_schema.dump(user)

5. Limiting Depth of Nested Serialization:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class OrderSchema(ma.Schema):
    items = ma.Nested(ItemSchema, depth=1)

order_schema = OrderSchema()
order_dict = order_schema.dump(order)

6. Automating Serialization:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class User(ma.Model):
    name = ma.String()
    email = ma.String()

user = User()
user_dict = user.dump()

7. Customizing Serialization Fields:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class ProductSchema(ma.Schema):
    price = ma.Decimal(as_string=True)

product_schema = ProductSchema()
product_dict = product_schema.dump(product)

8. Serializing to Different Formats:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()

user_schema = UserSchema()
user_json = user_schema.dump(user, output_format='json')
user_xml = user_schema.dump(user, output_format='xml')

9. Validating Input:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(required=True)
    email = ma.String(required=True)

user_schema = UserSchema()
errors = user_schema.validate(user_data)

10. Loading and Deserializing Input:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.String()

user_schema = UserSchema()
user = user_schema.load(user_data)

11. Overriding Default Serialization Behavior:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.String()

    def get_name(self, obj):
        return obj.name.upper()

user_schema = UserSchema()
user_dict = user_schema.dump(user)

12. Using Custom Serializers:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class CustomSerializer(ma.Serializer):
    def serialize(self, value):
        return value.upper()

user_schema = ma.Schema(serializer=CustomSerializer)
user_dict = user_schema.dump(user)

13. Filtering by Boolean Values:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    is_active = ma.Boolean()

user_schema = UserSchema()
filtered_user_dict = user_schema.dump(user, only=('name',))

14. Validating Nested Objects:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(required=True)
    orders = ma.Nested(OrderSchema, validate=True, many=True)

order_schema = ma.Schema()
errors = user_schema.validate(user_data)

15. Conditional Serialization:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.String()

    def should_show_email(self, obj):
        return obj.is_admin

    class Meta:
        exclude = ('email',)
        conditionals = {
            'email': should_show_email
        }

user_schema = UserSchema()
user_dict = user_schema.dump(user)

16. Recursive Serialization:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    children = ma.Nested(lambda: UserSchema, many=True)

user_schema = UserSchema()
user_dict = user_schema.dump(user)

17. Specifying Field Path in Errors:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(required=True)
    orders = ma.Nested(OrderSchema, required=True, many=True)

order_schema = ma.Schema()
errors = user_schema.validate(user_data)

18. Dynamic Schema Generation:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

def generate_user_schema(fields):
    return ma.Schema(fields=fields)

user_schema = generate_user_schema(('name', 'email'))
user_dict = user_schema.dump(user)

19. Handling Multiple Level Nested Objects:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class OrderSchema(ma.Schema):
    items = ma.Nested(ItemSchema, many=True)

class UserSchema(ma.Schema):
    orders = ma.Nested(OrderSchema, many=True)

user_schema = UserSchema()
user_dict = user_schema.dump(user)

20. Advanced Conditional Serialization:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.String()

    def should_show_email(self, obj):
        return obj.is_admin or obj.is_staff

    class Meta:
        exclude = ('email',)
        conditionals = {
            'email': should_show_email
        }

user_schema = UserSchema()
user_dict = user_schema.dump(user)

21. Serializing and Deserializing Relationships:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    orders = ma.Relationship(OrderSchema, many=True, backref='user')

order_schema = ma.Schema()
user_dict = user_schema.dump(user)

22. Custom Error Handling:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(required=True)
    email = ma.String()

    class Meta:
        error_messages = {
            'required': 'This field is required.'
        }

user_schema = UserSchema()
errors = user_schema.validate(user_data)

23. Using JSONAPI Serialization:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.ModelSchema):
    class Meta:
        include_fk = True

user_schema = UserSchema()
user_dict = user_schema.dump(user)

24. Controlling Field Serialization Order:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.String()

    class Meta:
        ordered = True

user_schema = UserSchema()
user_dict = user_schema.dump(user)

25. Customizing Swagger/OpenAPI Documentation:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.String()

    class Meta:
        swagger = {
            'description': 'User model'
        }

user_schema = UserSchema()
user_dict = user_schema.dump(user)

26. Menggunakan Skemata Terikat:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class User(ma.Model):
    name = ma.String()
    email = ma.String()

user_schema = ma.Schema.from_dict(User.query.first().to_dict())
user_dict = user_schema.dump(user)

27. Mengatur Perilaku Deserialisasi:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.String()

    class Meta:
        partial = True

user_schema = UserSchema()
updated_user = user_schema.load(updated_user_data, partial=True)

28. Menggunakan Pengurai Dasar:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.RawSchema):
    name = ma.String()
    email = ma.String()

user_schema = UserSchema()
user_dict = user_schema.dump(user)

29. Menangani Serialisasi Tertunda:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(load_from='full_name')
    email = ma.String()

user_schema = UserSchema()
user_dict = user_schema.dump(user)

30. Menggunakan Serializer Kustom:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSerializer(ma.Serializer):
    def serialize(self, value):
        return value.upper()

user_schema = ma.Schema(serializer=UserSerializer)
user_dict = user_schema.dump(user)

31. Menggunakan Filter dan Sort:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(filterable=True, sortable=True)
    email = ma.String(filterable=True)

user_schema = UserSchema()
filtered_sorted_users = user_schema.dump(User.query.filter(User.name=='John').order_by(User.name))

32. Memvalidasi Input dengan Skemata:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String(required=True)
    email = ma.Email(required=True)

user_schema = UserSchema()
errors = user_schema.validate(user_data)

33. Menggunakan Skemata Hierarkis:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class AddressSchema(ma.Schema):
    street = ma.String()
    city = ma.String()

class UserSchema(ma.Schema):
    name = ma.String()
    address = ma.Nested(AddressSchema)

user_schema = UserSchema()
user_dict = user_schema.dump(user)

34. Menangani Siklus Objek:

from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    friends = ma.Nested(lambda: UserSchema, many=True)

user_schema = UserSchema()
user_dict = user_schema.dump(user)

35. Menggunakan Skemata untuk Pengontrol:

from flask import Flask, jsonify

app = Flask(__name__)
ma = Marshmallow()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.String()

@app.route('/users')
def get_users():
    users = User.query.all()
    user_schema = UserSchema()
    users_dict = user_schema.dump(users, many=True)
    return jsonify(users_dict)

36. Menggunakan Skemata untuk Formulir Web:

from flask_wtf import Form
from flask_marshmallow import Marshmallow

ma = Marshmallow()

class UserForm(Form):
    name = wtforms.StringField()
    email = wtforms.EmailField()

class UserSchema(ma.Schema):
    name = ma.String()
    email = ma.Email()

@app.route('/users', methods=['POST'])
def create_user():
    form = UserForm()
    if form.validate_on_submit():
        data = form.data
        user_schema = UserSchema()
        user = user_schema.load(data)
        db.session.add(user)
        db.session.commit()
        return jsonify(user_schema.dump(user))
    return jsonify(errors=form.errors)