Decimal や datetime の入った JSON 風オブジェクトを loguru 向けにダンプして出力するクラス

tmp.ODH1kHzxnH.py

"""
Decimal や datetime の入った JSON 風オブジェクトを loguru 向けにダンプして出力するクラス
"""

import datetime
import json
from decimal import Decimal
from typing import Any

import requests
from loguru import logger
from rich.pretty import pprint


class JSONLog:
    def __init__(self, message: Any):
        self.message = message

    @staticmethod
    def default(obj: Any):
        match obj:
            case Decimal():
                return float(obj)
            case datetime.datetime():
                return obj.isoformat()
            case _:
                return str(obj)

    def __str__(self) -> str:
        return json.dumps(
            self.message, ensure_ascii=False, indent=4, default=self.default
        )


r = requests.get("https://api.bitflyer.com/v1/ticker")
ticker = r.json()

for key in ("timestamp",):
    ticker[key] = datetime.datetime.fromisoformat(ticker[key])

for key in (
    "best_bid",
    "best_ask",
    "best_bid_size",
    "best_ask_size",
    "total_bid_depth",
    "total_ask_depth",
    "market_bid_size",
    "market_ask_size",
    "ltp",
    "volume",
    "volume_by_product",
):
    ticker[key] = Decimal(str(ticker[key]))

pprint(ticker, indent_guides=False)

""" ※ この形式だと JSON ダンプできない
{
    'product_code': 'BTC_JPY',
    'state': 'RUNNING',
    'timestamp': datetime.datetime(2023, 7, 4, 7, 59, 16, 377000),
    'tick_id': 14380026,
    'best_bid': Decimal('4481077.0'),
    'best_ask': Decimal('4481132.0'),
    'best_bid_size': Decimal('0.01'),
    'best_ask_size': Decimal('0.022'),
    'total_bid_depth': Decimal('636.31801651'),
    'total_ask_depth': Decimal('306.85054554'),
    'market_bid_size': Decimal('0.0'),
    'market_ask_size': Decimal('0.0'),
    'ltp': Decimal('4481077.0'),
    'volume': Decimal('4011.33397438'),
    'volume_by_product': Decimal('1756.56323256')
}
"""

logger.info(JSONLog(ticker))

"""
2023-07-04 16:59:17.139 | INFO     | __main__:<module>:78 - {
    "product_code": "BTC_JPY",
    "state": "RUNNING",
    "timestamp": "2023-07-04T07:59:16.377000",
    "tick_id": 14380026,
    "best_bid": 4481077.0,
    "best_ask": 4481132.0,
    "best_bid_size": 0.01,
    "best_ask_size": 0.022,
    "total_bid_depth": 636.31801651,
    "total_ask_depth": 306.85054554,
    "market_bid_size": 0.0,
    "market_ask_size": 0.0,
    "ltp": 4481077.0,
    "volume": 4011.33397438,
    "volume_by_product": 1756.56323256
}
"""