如果对象键值在python中相同，则合并字典

Question

我需要根据字典列表中的对象合并一些字典的帮助。这可能吗？

我的数据：

mongo_data = [{
 'url': 'https://goodreads.com/',
 'variables': [{'key': 'Harry Potter', 'value': '10.0'},
               {'key': 'Discovery of Witches', 'value': '8.5'},],
 'vendor': 'Fantasy' 
 },{
 'url': 'https://goodreads.com/',
 'variables': [{'key': 'Hunger Games', 'value': '10.0'},
               {'key': 'Maze Runner', 'value': '5.5'},],
 'vendor': 'Dystopia' 
 },{
 'url': 'https://kindle.com/',
 'variables': [{'key': 'Twilight', 'value': '5.9'},
               {'key': 'Lord of the Rings', 'value': '9.0'},],
 'vendor': 'Fantasy' 
 },{
 'url': 'https://kindle.com/',
 'variables': [{'key': 'The Handmaids Tale', 'value': '10.0'},
               {'key': 'Divergent', 'value': '9.0'},],
 'vendor': 'Fantasy' 
 }]

我的代码：

我使用 [groupby] 将具有相同 URL 的项目组合在一起。

from itertools import groupby, chain
import json

searches = []
for key, group in groupby(mongo_data, key=lambda chunk: chunk['url']):
    search = {}
    search["url"] = key
    search["results"] = [{"genre": result["vendor"], "data": result["variables"]} for result in group]
    searches.append(search)

print(json.dumps(searches))

我的输出

[
  {
    "url": "https://goodreads.com/",
    "results": [
      {
        "genre": "Fantasy",
        "data": [
          {
            "key": "Harry Potter",
            "value": "10.0"
          },
          {
            "key": "Discovery of Witches",
            "value": "8.5"
          }
        ]
      },
      {
        "genre": "Dystopia",
        "data": [
          {
            "key": "Hunger Games",
            "value": "10.0"
          },
          {
            "key": "Maze Runner",
            "value": "5.5"
          }
        ]
      }
    ]
  },
  {
    "url": "https://kindle.com/",
    "results": [
      {
        "genre": "Fantasy",
        "data": [
          {
            "key": "Twilight",
            "value": "5.9"
          },
          {
            "key": "Lord of the Rings",
            "value": "9.0"
          }
        ]
      },
      {
        "genre": "Fantasy",
        "data": [
          {
            "key": "The Handmaids Tale",
            "value": "10.0"
          },
          {
            "key": "Divergent",
            "value": "9.0"
          }
        ]
      }
    ]
  }
]

正如您在https://kindle.com/ 下看到的那样，我有两次"genre":"Fantasy"。而不是打印两次。我可以在没有重复的情况下合并它们吗？

所以我希望我的预期结果是：

{
    "url": "https://kindle.com/",
    "results": [
      {
        "genre": "Fantasy",
        "data": [
          {
            "key": "Twilight",
            "value": "5.9"
          },
          {
            "key": "Lord of the Rings",
            "value": "9.0"
          },
          {
            "key": "The Handmaids Tale",
            "value": "10.0"
          },
          {
            "key": "Divergent",
            "value": "9.0"
          }
        ]
      }
    ]
  }
]

这可能吗？

Answer 1

您需要第二个 groupby 来按供应商对结果进行分组。

例如：

searches = []
for key, group in groupby(mongo_data, key=lambda chunk: chunk['url']):
    search = {"url": key, "results": []}
    for vendor, group2 in groupby(group, key=lambda chunk2: chunk2['vendor']):
        result = {
            "genre": vendor,
            "data": [{"key": key, "value": value}
                     for result2 in group2
                     for key, value in result2["variables"]],
        }
        search["results"].append(result)
    searches.append(search)

理解列表用于展平result2["variables"] 并避免列表列表。

结果是：

[
 {
  "url": "https://goodreads.com/",
  "results": [
   {
    "genre": "Fantasy",
    "data": [
     {
      "key": "key",
      "value": "value"
     },
     {
      "key": "key",
      "value": "value"
     }
    ]
   },
   {
    "genre": "Dystopia",
    "data": [
     {
      "key": "key",
      "value": "value"
     },
     {
      "key": "key",
      "value": "value"
     }
    ]
   }
  ]
 },
 {
  "url": "https://kindle.com/",
  "results": [
   {
    "genre": "Fantasy",
    "data": [
     {
      "key": "key",
      "value": "value"
     },
     {
      "key": "key",
      "value": "value"
     },
     {
      "key": "key",
      "value": "value"
     },
     {
      "key": "key",
      "value": "value"
     }
    ]
   }
  ]
 }
]

Answer 2

如果你想要一个“单行”（？），试试这个：

{"url": "https://kindle.com/", "results": [{"genre": k,"data": [v]} for k, v in {g:[y for x in [x['variables'] for x in mongo_data if x['vendor'] == g] for y in x] for g in set(x['vendor'] for x in mongo_data)}.items()]}

它产生

{
    'url': 'https://kindle.com/',
    'results': [
        {
            'genre': 'Fantasy',
            'data': [
                [
                    {'key': 'Harry Potter', 'value': '10.0'},
                    {'key': 'Discovery of Witches', 'value': '8.5'},
                    {'key': 'Twilight', 'value': '5.9'},
                    {'key': 'Lord of the Rings', 'value': '9.0'},
                    {'key': 'The Handmaids Tale', 'value': '10.0'},
                    {'key': 'Divergent', 'value': '9.0'}
                ]
            ]
        },

        {
            'genre': 'Dystopia',
            'data': [
                [
                    {'key': 'Hunger Games', 'value': '10.0'},
                    {'key': 'Maze Runner', 'value': '5.5'}
                ]
            ]
        }
    ]
}

Answer 3

您可以在 for 循环之后使用此代码来完成您提到的内容：

from collections import defaultdict

for item in searches:
    results = item['results']
    _res = defaultdict(list)
    for r in results:
        _res[r['genre']].append(r['data'])

    item['data'] = [{
        'genre': k,
        'data': _res[k]
    } for k in _res.keys()]