使用词典理解和 If/Else 条件从 API 响应中选择 key/value 对

Question

我已经编制了一份名为“user_responses”的 API 响应列表。这是列表中的响应示例：

{
    "ok": true,
    "members": [
        {
            "id": "W012A3CDE",
            "team_id": "T012AB3C4",
            "name": "spengler",
            "deleted": false,
            "color": "9f69e7",
            "real_name": "spengler",
            "tz": "America/Los_Angeles",
            "tz_label": "Pacific Daylight Time",
            "tz_offset": -25200,
            "profile": {
                "avatar_hash": "ge3b51ca72de",
                "status_text": "Print is dead",
                "status_emoji": ":books:",
                "real_name": "Egon Spengler",
                "display_name": "spengler",
                "real_name_normalized": "Egon Spengler",
                "display_name_normalized": "spengler",
                "email": "spengler@ghostbusters.example.com",
                "image_24": "https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg",
                "image_32": "https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg",
                "image_48": "https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg",
                "image_72": "https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg",
                "image_192": "https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg",
                "image_512": "https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg",
                "team": "T012AB3C4"
            },
            "is_admin": true,
            "is_owner": false,
            "is_primary_owner": false,
            "is_restricted": false,
            "is_ultra_restricted": false,
            "is_bot": false,
            "updated": 1502138686,
            "is_app_user": false,
            "has_2fa": false
        },
        {
            "id": "W07QCRPA4",
            "team_id": "T0G9PQBBK",
            "name": "glinda",
            "deleted": false,
            "color": "9f69e7",
            "real_name": "Glinda Southgood",
            "tz": "America/Los_Angeles",
            "tz_label": "Pacific Daylight Time",
            "tz_offset": -25200,
            "profile": {
                "avatar_hash": "8fbdd10b41c6",
                "image_24": "https://a.slack-edge.com...png",
                "image_32": "https://a.slack-edge.com...png",
                "image_48": "https://a.slack-edge.com...png",
                "image_72": "https://a.slack-edge.com...png",
                "image_192": "https://a.slack-edge.com...png",
                "image_512": "https://a.slack-edge.com...png",
                "image_1024": "https://a.slack-edge.com...png",
                "image_original": "https://a.slack-edge.com...png",
                "first_name": "Glinda",
                "last_name": "Southgood",
                "title": "Glinda the Good",
                "phone": "",
                "skype": "",
                "real_name": "Glinda Southgood",
                "real_name_normalized": "Glinda Southgood",
                "display_name": "Glinda the Fairly Good",
                "display_name_normalized": "Glinda the Fairly Good",
                "email": "glenda@south.oz.coven"
            },
            "is_admin": true,
            "is_owner": false,
            "is_primary_owner": false,
            "is_restricted": false,
            "is_ultra_restricted": false,
            "is_bot": false,
            "updated": 1480527098,
            "has_2fa": false
        }
    ],
    "cache_ts": 1498777272,
    "response_metadata": {
        "next_cursor": "dXNlcjpVMEc5V0ZYTlo="
    }
}

我想构建一个包含以下内容的字典：

1.一个键就是用户的 real_name。如果用户没有 real_name 那么我想为用户使用 display_name。

为此，我尝试在字典理解中使用三元表达式来处理 if/else 条件：

{(sub_dict['profile']['real_name'] if 'real_name' in sub_dict['profile] 
  else sub_dict['profile']['display_name']):value
  for response in user_responses
  for sub_dict in response.get('members')}

这似乎只是默认为每个用户使用 display_name，这不是我想要的。

2。一个值，它是每个用户的所有图像的列表。

为此，我想我可以编写一个列表理解，其中包含以单词“image”开头的所有键的值。

{(key:[sub_dict['profile'][k] for k in sub_dict['profile'] if k.startswith('image')]
  for response in user_responses
  for sub_dict in response.get('members')}

有没有更好的方法来完成这个？在此先感谢您的帮助。

Answer 1

将 for-loops 简化为推导式的一个好方法是首先使用常规 for 循环可视化该过程：

newLst = []
for member in var["members"]:
    d = {"images": []}
    for k, v in member["profile"].items():
        if k.startswith("image"):
            d["images"].append(v)

    d["name"] = member["profile"].get("real_name")
    if not d["name"]:
        member["profile"].get("display_name")
    newLst.append(d)

现在，我个人会选择上述 for-loop。但是，您的问题是如何使用理解来解决它，所以这是我的版本：

newLst = [{"images": [v for k, v in member["profile"].items() if k.startswith("image")],
            "name": member["profile"].get("real_name", member["profile"].get("display_name"))} for member in var["members"]]

两者的最大区别在于第一个很容易调试，或者至少遵循逻辑。虽然第二个很难真正跟上。

两者的结果：

[{'images': ['https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg',
             'https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg',
             'https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg',
             'https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg',
             'https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg',
             'https://.../avatar/e3b51ca72dee4ef87916ae2b9240df50.jpg'],
  'name': 'Egon Spengler'},
 {'images': ['https://a.slack-edge.com...png',
             'https://a.slack-edge.com...png',
             'https://a.slack-edge.com...png',
             'https://a.slack-edge.com...png',
             'https://a.slack-edge.com...png',
             'https://a.slack-edge.com...png',
             'https://a.slack-edge.com...png',
             'https://a.slack-edge.com...png'],
  'name': 'Glinda Southgood'}]

使用词典理解和 If/Else 条件从 API 响应中选择 key/value 对

Selecting key/value pairs from API Response using Dictionary Comprehension with If/Else conditions

python

api

json

list-comprehension

dictionary-comprehension