从 zipfile 中提取并合并多个 shapefile 而无需保存到光盘

Question

我第一次在 Python 中使用 zipfiles :-/

手头的任务如下（主要要求是不向光盘写入任何内容）

鉴于此 url：http://shapefiles.fews.net.s3.amazonaws.com/ALL_HFIC.zip

获取 zip 文件
从文件名中包含 Africa 的 zip arcvhie 中提取形状文件。
将所有文件合并为一个 shapefile（将所有文件读入 geopandas）。
转换为 geoJson。

这是我目前的代码结构 - 但我一直收到属性错误

AttributeError: 'ZipFile' object has no attribute 'seek'

import io
import zipfile
import pandas as pd     
import geopandas as gpd 

# util funcs
is_africa = lambda string: "Africa" in string                                
is_shape = lambda string: string.endswith('shp')

# get_zip() defined in module
filebytes = io.BytesIO(get_zip(url=URL).content)  

# get the zipfile object
myzipfile = zipfile.ZipFile(filebytes)
                                                               
# instantiate empty list where to store the shapefiles of interest.      
shapefiles = []

# below code adapted from:                                                                                                
with zipfile.ZipFile(zip_file, 'r') as zf:                               
    for file_name in zf.namelist():                                      
        if is_africa(file_name) and is_shape(file_name):                 
            data = zf.read(file_name)                                    
            shapefiles.append(data)                                      


# below code adapted from                                                                          
gdf_africa = gpd.GeoDataFrame(pd.concat([gpd.read_file(i) for i in shapefiles], 
                                        ignore_index=True), 
                              crs=gpd.read_file(shapefiles[0]).crs)   

gdf_africa.to_file("output.json", driver="GeoJSON")

Answer 1

此代码从 URL 请求 ZipFile，将 ZipFile 读取到流中并提取非洲 ShapeFile 的名称。

from zipfile import ZipFile
import requests

# util funcs
is_africa = lambda string: "Africa" in string
is_shape = lambda string: string.endswith('shp')

# instantiate empty list where to store the shapefiles of interest.
africa_data = []

response = requests.get('http://shapefiles.fews.net.s3.amazonaws.com/ALL_HFIC.zip')
with ZipFile(io.BytesIO(response.content)) as zf:
    for file_name in zf.namelist():
       if is_africa(file_name) and is_shape(file_name):
         print(file_name)
         # Output
         ALL_HFIC/ALL_HFIC/East Africa/EA_200907_CS.shp
         ALL_HFIC/ALL_HFIC/East Africa/EA_200910_CS.shp
         ALL_HFIC/ALL_HFIC/East Africa/EA_201001_CS.shp
         ALL_HFIC/ALL_HFIC/East Africa/EA_201004_CS.shp

我从未使用过ShapeFiles或geopandas。我花了最后 4 个小时试图了解如何使用这些。我能够输出一个 JSON 文件，但我不确定这个 JSON 文件中的数据是否满足您的需要。

# util funcs
is_africa = lambda string: "Africa" in string
is_shape = lambda string: string.endswith('shp')

# instantiate empty list where to store the shapefiles of interest.
africa_data = []

response = requests.get('http://shapefiles.fews.net.s3.amazonaws.com/ALL_HFIC.zip')
with ZipFile(io.BytesIO(response.content)) as zf:
    for file_name in zf.namelist():
       if is_africa(file_name) and is_shape(file_name):
         reader = shapefile.Reader(file_name)
         fields = reader.fields[1:]
         field_names = [field[0] for field in fields]
         for sr in reader.shapeRecords():
            atr = dict(zip(field_names, sr.record))
            geom = sr.shape.__geo_interface__
            africa_data.append(dict(type="Feature", geometry=geom, properties=atr))

    geojson = open("african_geo_data.json", "w")
    geojson.write(dumps({"type": "FeatureCollection", "features": africa_data}, indent=2) + "\n")
    geojson.close()

从 JSON 文件中抽样：

{
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "geometry": {
      "type": "MultiPolygon",
       "coordinates": [
         [
           [
            [
              40.213226318000125,
              -10.277393340999765
            ],
            [
              40.21355056800013,
              -10.279667853999932
            ],
            [
              40.21699915800019,
              -10.27847569599988
            ]
          },
          "properties": {
          "CS": 4.0,
          "HA0": 0.0
          }
        }
       ]
      }

从 zipfile 中提取并合并多个 shapefile 而无需保存到光盘

extract and merge several shapefiles from zipfile without saving to disc

zip

shapefile

geo

python-3.x

geopandas