Использование Pydantic сегодня стало нормой, и это правильно. Но иногда на ревью вижу, что используют его не всегда корректно.
Например, метод BaseModel.model_dump() по умолчанию не преобразует стандартные типы, такие как datetime, UUID или Decimal, в простой сериализуемый для JSON вид. Тогда пишут кастмоный сериализатор для этих типов чтобы функция json.dump() не падала с ошибкой.
import uuid
from datetime import datetime
from decimal import Decimal
from uuid import UUID
from pydantic import BaseModel
class MyModel(BaseModel):
id: UUID
date: datetime
value: Decimal
obj = MyModel(
id=uuid.uuid4(),
date=datetime.now(),
value='1.23'
)
print(obj.model_dump())
# не подходит для json.dump
# {
# 'id': UUID('4f8c1bc4-25fd-40cd-9dbe-2c73639b0dc1'),
# 'date': datetime.datetime(2025, 12, 12, 12, 12, 12, 111111),
# 'value': Decimal('1.23')
# }
# добавляем свой кастомный сериализатор
json.dumps(obj.model_dump(), cls=MySerializer)
# {
# 'id': '4f8c1bc4-25fd-40cd-9dbe-2c73639b0dc1',
# 'date': '2025-12-12T12:12:12.111111',
# 'value': '1.23'
# }
В данном случае класс MySerializer обрабатывает datetime, UUID и Decimal. Например так:
class MySerializer(json.JSONEncoder):
def default(self, o):
if isinstance(o, Decimal):
return str(o)
elif isinstance(o, datetime):
return o.isoformat()
elif isinstance(o, UUID):
return str(o)
return super().default(o)
Специально для тех, кто всё еще так делает - в этом нет необходимости!
Pydantic может это сделать сам, просто нужно добавить параметр mode="json".
json.dumps(obj.model_dump(mode="json"))
# {
# 'id': '4f8c1bc4-25fd-40cd-9dbe-2c73639b0dc1',
# 'date': '2012-12-12T12:12:12.111111',
# 'value': '1.23'
# }
#pydantic#libs
#MyGov पल्स - सिटीजन कनेक्ट पाक्षिक न्यूज़लेटर के इस अंक में 2023 में भारत की ऐतिहासिक उपलब्धियों और #ViksitBharat की दिशा में प्रगति से संबंधित उपलब्धियों को जानें।
पूरा पढ़ें: https://static.mygov.in/static/s3fs-public/mygov_170349057782937911.pdf
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To watch the full episode, visit: https://www.youtube.com/watch?v=mmZFDtR_LrE
सहकारिता - विकसित भारत की असली ताकत!
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आइए इस 🧵 द्वारा जानें: https://x.com/i/status/2030890080014156147
#SahkarSeSamriddhi#ViksitBharat
This week, MyGov India hosts Soumitra Dutta, professor at the University of Oxford and author of 'From Gridlock to Growth: How Leadership Enables India's Pragati Ecosystem to Power Progress'.
Explore how PRAGATI has transformed the delivery of major infrastructure projects and propelled India’s progress to new heights.
Don’t miss this opportunity to gain valuable insights into the transformative journey of #NewIndia!
Watch the full episode: https://youtu.be/VTp4fv1H31k
#PRAGATI
#ViksitBharat
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Join us for this week’s #FridaysAtMyGov as people share their experiences with AI’s growing influence in India
Watch the full episode now:
https://youtu.be/_OIwATkwTUU
#AI
#ViksitBharat
#IndiaRising
All aboard the future of rail travel!🚆
This #FridaysAtMyGov, experience the engineering marvel #VandeBharat Express, now connecting Delhi to Srinagar under the visionary #MakeInIndia initiative. Ready to tackle snow, designed for comfort, and built for innovation, it's a symbol of #ViksitBharat in motion.
Watch the full video now: https://www.youtube.com/watch?v=LmufFHQY2gc
#NewIndia
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A day that honours the spirit of NRIs, proving that distance can never weaken their connection with Bharat
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🎥 To watch the full video, visit: https://youtu.be/-g65oAFX5Yg?si=n1XUY7r1c66BnkRs
#ViksitBharat
#NewIndia
#PBD2025
5 Crore Voices. 5 Crore Dreams. 5 Crore Saathis.
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Thank you to every Saathi for being a part of this vibrant community! Let's continue to engage, inspire, and shape a #ViksitBharat together.
#5CroreSaathis
#MyGovSaathis
#NewIndia
'करेंगे और कर के रहेंगे' विकसित भारत का संकल्प!
On August 9, 1942, we united with a powerful resolve for freedom.
#QuitIndiaMovement#UnityInStrength#TransformingIndia#ViksitBharat
Get ready for another thrilling episode of Fridays At MyGov!
Join us as we take you inside the cutting-edge Namo Bharat Rapid Train, redefining travel with its air-conditioned, secure, and modern features. It's not just a ride—it's an experience of convenience and innovation!
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Stay tuned for more episodes celebrating Viksit Bharat.
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