Python根据字典数组中的键对json排序

Question

I have a structure like this:

[{
    "name": "apple",
    "price": "5.0",
    "record": [
        {
            "id": "008",
            "time": 1465689600
        }
    ] 
},{
    "name": "banana",
    "price": "9.0",
    "record": [
        {
            "id": "002",
            "time": 1465682600
        }
    ]
}]

I tried below but it gave me an error: string indices must be integers.

sorted(lines, key=lambda k: k['record'].get('time', 0),reverse=True)

How do I sort the above based on the "time" value?

Thanks.

Answer 1

Apparently, your structure is a string. You need to convert it to a python object using json.loads

import json

d = "[{'record': [{'id': '008', 'time': 1465689600}], 'price': '5.0', 'name': 'apple'}, {'record': [{'id': '002', 'time': 1465682600}], 'price': '9.0', 'name': 'banana'}]"

lines = json.loads(d)
sorted(lines, key=lambda k: k['record'][0].get('time', 0), reverse=True)
#                                       ^

Thereafter, the value at the key 'record' is a list. The list has one dict object at index 0. So you need to access the dict object first, then you can access the values of the dictionary.

Answer 2

Since this is a json, I would just decode it using json.loads :

import json

lines = '''
[{
    "name": "apple",
    "price": "5.0",
    "record": [
        {
            "id": "008",
            "time": 1465689600
        }
    ] 
},{
    "name": "banana",
    "price": "9.0",
    "record": [
        {
            "id": "002",
            "time": 1465682600
        }
    ]
}]
'''

d = json.loads(lines)

for x in sorted(d, key=lambda k: k['record'][0].get('time', 0), reverse=True):
    print x

Output:

{u'record': [{u'id': u'008', u'time': 1465689600}], u'price': u'5.0', u'name': u'apple'}
{u'record': [{u'id': u'002', u'time': 1465682600}], u'price': u'9.0', u'name': u'banana'}