Python:从http到csv

Question

我需要将 HTTP 中的字符串写入 CSV 文件。 我的列必须是:LATITUDE、LONGITUDE、OSM_ID、HIGHWAY、UPDATED_AT

这是从顶部开始的 HTTP 链接的输出示例:

{
  "datetime": "2018-06-08T08:26:09.375Z",
  "success": true,
  "bbox": {
    "xmin": "12.335513",
    "ymin": "42.035682",
    "xmax": "12.758896",
    "ymax": "42.050826"
  },
  "data": [
    {
      "aggregate_id": 30201274,
      "ppe": 0.316954620298806,
      "geom": {
        "type": "Point",
        "coordinates": [
          12.532972800901,
          42.045435384225
        ]
      },
      "osm_id": "37015042",
      "highway": "motorway",
      "updated_at": "2018-01-20T03:27:11.047Z"
    },
    {
      "aggregate_id": 30201275,
      "ppe": 0.318124963244448,
      "geom": {
        "type": "Point",
        "coordinates": [
          12.5329908742,
          42.045615145535
        ]
      },
      "osm_id": "37015042",
      "highway": "motorway",
      "updated_at": "2018-01-20T03:27:11.047Z"
    },
    {
      "aggregate_id": 30201276,
      "ppe": 0.204792151096739,
      "geom": {
        "type": "Point",
        "coordinates": [
          12.533008947499,
          42.045794906844
        ]
      },
      "osm_id": "37015042",
      "highway": "motorway",
      "updated_at": "2018-01-20T03:27:11.047Z"
    },
    {
      "aggregate_id": 30201277,
      "ppe": 0.194797261691664,
      "geom": {
        "type": "Point",
        "coordinates": [
          12.533030586679,
          42.045974206816
        ]
      },
      "osm_id": "37015042",
      "highway": "motorway",
      "updated_at": "2018-01-20T03:27:11.047Z"
    }
  ]
}

每行用“,”分隔。

这段代码是我写的

import pandas as pd
import csv
import urllib.request

from urllib.request import urlopen

CSV_URL = 'http://www.smartroadsense.it/bb/12.335513/42.035682/12.758896/42.050826'

request = urllib.request.Request(CSV_URL)
response = urllib.request.urlopen(request)
response.read().decode('utf-8')

#write into csv
colNames = ["longitude","latitude","ppe","osm_id","highway","updated_at"]
data = pd.read_csv(CSV_URL, names=colNames, sep=',')

问题是如何将 http 中的字符串拆分为行。有人可以帮助我吗？

Answer 1

这是使用 pandas 和 requests 的简单实现:

import pandas as pd
import requests

url = 'http://www.smartroadsense.it/bb/12.335513/42.035682/12.758896/42.050826'
response = requests.get(url).json()

df = pd.DataFrame(response['data'])

您可以从 geom 列中提取经度和纬度，如下所示:

df['longitude'] = df.apply(lambda row: dict(row['geom'])['coordinates'][0], axis=1)
df['latitude'] = df.apply(lambda row: dict(row['geom'])['coordinates'][1], axis=1)

最后，将所需的列保存到 csv 文件中，如下所示:

df[['latitude', 'longitude', 'osm_id', 'highway', 'updated_at']].to_csv('output.csv', index=False)