完成函数时找不到临时文件

Question

我正在尝试创建一个tempfile，写入它，然后从我的flask应用程序下载它。但是，我在完成函数时收到FileNotFoundError。这是我的代码& &;收到的错误。提前谢谢。

with tempfile.TemporaryFile (mode='w', newline="", dir=".", suffix='.csv') as csvfilenew:
writer = csv.writer(csvfilenew, delimiter= ';')
myClick()
return send_file(str(csvfilenew.name), as_attachment=True, attachment_filename='cleanfile.csv')

FileNotFoundError: [Errno 2] No such file or directory: '/Desktop/bulk_final/10'

Answer 1

TemporaryFile在请求name属性时没有返回有效的文件描述符。您可以使用NamedTemporaryFile询问名称。

from flask import send_file
import tempfile
import csv
@app.route('/download')
def download():
with tempfile.NamedTemporaryFile(mode='w', newline='', dir='.', suffix='.csv') as csvfilenew:
writer = csv.writer(csvfilenew, delimiter= ';')
writer.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])
csvfilenew.flush()
csvfilenew.seek(0)
return send_file(csvfilenew.name,
as_attachment=True,
attachment_filename='cleanfile.csv'
)

另一个处理少量数据的简单方法如下:

from flask import send_file
import csv
import io
@app.route('/download')
def download():
with io.StringIO() as doc:
writer = csv.writer(doc, delimiter= ';')
writer.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])
doc.seek(0)
return send_file(io.BytesIO(doc.read().encode('utf8')),
as_attachment=True,
attachment_filename='cleanfile.csv'
)