Question

解析文件时

<html>
    <head><meta charset="UTF-8"></head>
    <body><a href="Düsseldorf.html">Düsseldorf</a></body>
</html>

使用

item = SimpleItem()
item['name'] = response.xpath('//a/text()')[0].extract()
item["url"] = response.xpath('//a/@href')[0].extract()
return item

我最终得到\u转义

[{
    "name": "D\u00fcsseldorf",
    "url": "D\u00fcsseldorf.html"
}]

或使用百分比编码的字符串

D%C3%BCsseldorf

item exporter描述了here

# -*- coding: utf-8 -*-
import json
from scrapy.contrib.exporter import BaseItemExporter

class UnicodeJsonLinesItemExporter(BaseItemExporter):

    def __init__(self, file, **kwargs):
        self._configure(kwargs)
        self.file = file
        self.encoder = json.JSONEncoder(ensure_ascii=False, **kwargs)

    def export_item(self, item):
        itemdict = dict(self._get_serialized_fields(item))
        self.file.write(self.encoder.encode(itemdict) + '\n')

以及相应的Feed导出设置

FEED_EXPORTERS = {
    'json': 'myproj.exporter.UnicodeJsonLinesItemExporter',
}

没有帮助。

如何获得utf-8编码的JSON输出？

我重申/扩展unanswered question。

更新：

与Scrapy正交，请注意不设置

export PYTHONIOENCODING="utf_8"

运行

> echo { \"name\": \"Düsseldorf\", \"url\": \"Düsseldorf.html\" } > dorf.json
> python -c'import fileinput, json;print json.dumps(json.loads("".join(fileinput.input())),sort_keys=True, indent=4, ensure_ascii=False)' dorf.json > dorf_pp.json

将失败

Traceback (most recent call last):
  File "<string>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode character u'\xfc' in position 16: ordinal not in range(128)

更新

发布后，我的问题无法回答。 UnicodeJsonLinesItemExporter工作，但管道的另一部分是罪魁祸首：作为一个漂亮打印JSON输出的后期处理，我当时正在使用python -m json.tool in.json > out.json。

Answer 1

>>> a = [{
    "name": "D\u00fcsseldorf",
    "url": "D\u00fcsseldorf.html"
}]
>>> a
[{'url': 'Düsseldorf.html', 'name': 'Düsseldorf'}]
>>> json.dumps(a, ensure_ascii=False)
'[{"url": "Düsseldorf.html", "name": "Düsseldorf"}]'

Answer 2

这似乎对我有用

# -*- coding: utf-8 -*-
import scrapy
import urllib

class SimpleItem(scrapy.Item):
    name = scrapy.Field()
    url = scrapy.Field()

class CitiesSpider(scrapy.Spider):
    name = "cities"
    allowed_domains = ["sitercity.info"]
    start_urls = (
        'http://en.sistercity.info/countries/de.html',
    )

    def parse(self, response):
        for a in response.css('a'):
            item = SimpleItem()
            item['name'] = a.css('::text').extract_first()
            item['url'] = urllib.unquote(
                a.css('::attr(href)').extract_first().encode('ascii')
                ).decode('utf8')
            yield item

使用您问题中引用的Feed导出器，它也可以使用其他存储

# -*- coding: utf-8 -*-
import json
import io
import os
from scrapy.contrib.exporter import BaseItemExporter
from w3lib.url import file_uri_to_path

class CustomFileFeedStorage(object):

    def __init__(self, uri):
        self.path = file_uri_to_path(uri)

    def open(self, spider):
        dirname = os.path.dirname(self.path)
        if dirname and not os.path.exists(dirname):
            os.makedirs(dirname)
        return io.open(self.path, mode='ab')

    def store(self, file):
        file.close()

class UnicodeJsonLinesItemExporter(BaseItemExporter):

    def __init__(self, file, **kwargs):
        self._configure(kwargs)
        self.file = file
        self.encoder = json.JSONEncoder(ensure_ascii=False, **kwargs)

    def export_item(self, item):
        itemdict = dict(self._get_serialized_fields(item))
        self.file.write(self.encoder.encode(itemdict) + '\n')

（必要时删除评论）

FEED_EXPORTERS = {
    'json': 'myproj.exporter.UnicodeJsonLinesItemExporter'
}
#FEED_STORAGES = {
#   '': 'myproj.exporter.CustomFileFeedStorage'
#}
FEED_FORMAT = 'json'
FEED_URI = "out.json"

如何避免JSON百分比编码和\ u-escaping？

2 个答案: