"IndexError at / list index out of range"出现空列表时如何解决

Question

我想知道当 API "leverage_buy" 中有一个空列表时，在 Django 中 return null 最简单的方法是什么：[],:

我的views.py

from django.shortcuts import render
from meal_app.models import Kraken
import requests

def get_krakens(request):
    all_krakens = {}
    url ='https://api.kraken.com/0/public/AssetPairs' 
    response = requests.get(url)
    data = response.json()

    for i in data['result'].values():
        kraken_data = Kraken(
            altname = i['altname'], 
            leverage_buy = i['leverage_buy'][0],
            )
        kraken_data.save()

我的models.py

from django.db import models
class Kraken(models.Model):
    altname = models.CharField(max_length=50, blank = True, null = True)
    leverage_buy = models.IntegerField(blank=True, null=True)

邮递员回复

{
    "error": [],
    "result": {
        "1INCHEUR": {
            "altname": "1INCHEUR",
            "leverage_buy": [],

我在这里研究并尝试了很多类似的案例，但是none有一个API空列表的例子。

Answer 1

您可以使用三元运算符：

for i in data['result'].values():
    kraken_data = Kraken.objects.create(
        altname = i['altname'], 
        leverage_buy = <strong>i['leverage_buy'][0] if i['leverage_buy'] else None</strong>
    )

"IndexError at / list index out of range"出现空列表时如何解决

How to solve "IndexError at / list index out of range" when there is an empty list

api

django

django-rest-framework