一哥一射
问题描述
我正在尝试从内存中的 FTP 服务器下载文件，将其转换为数据帧，但也将其作为字节返回.代码如下:
I am trying to download a file from an FTP server in memory, transform it to a dataframe but also return it as bytes. Code as follows:
import io
import pandas as pd
from ftplib import FTP
ftp_connection.cwd(ftp_folder)
download_file = io.BytesIO()
ftp_connection.retrbinary('RETR ' + str(file_name), download_file.write)
download_file.seek(0)
file_to_process = pd.read_csv(download_file, engine='python')
在 Stack Overflow 上搜索后，建议只读取 io 流:
After searching on Stack Overflow, the suggestion was to just read the io stream:
download_file.read() ValueError: I/O operation on closed file.
不确定接下来要尝试什么，没有将文件写入某处并以字节形式再次读取.
Not sure what to try next, without writing the file somewhere and reading it again as bytes.
推荐答案
read_csv 可能会关闭文件".所以在调用 read_csv 之前请阅读它:
read_csv probably closes the "file". So read it before you call read_csv:
download_file.seek(0) contents = download_file.read() download_file.seek(0) file_to_process = pd.read_csv(download_file, engine='python')
