如何將列表保存到臨時目錄中的pickle文件並將該文件傳遞給函數？

Question

問題是，我從一個來源提取數據，我想將它保存到保存箱中作爲一個pickle文件。我無法將其保存在目錄中，因爲我正在服務器上運行代碼（iron.io）。

import tempfile 
import pickle 


def SFDCDropboxSync(Data): 
    f = tempfile.NamedTemporaryFile(delete=False) 
    pickle.dump(Data,open(f,'wb')) 

    client = dropbox.client.DropboxClient(access_token) 
    client.put_file(filename, f) 

這是我的錯誤：

Traceback (most recent call last): File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Shippy/RecurringDataDump/SFDCDropboxUpload.py", line 38, in <module> 
    if __name__ == "__main__": main() File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Shippy/RecurringDataDump/SFDCDropboxUpload.py", line 31, in main 
    print SFDCDropboxUploadDownload().SFDCDropboxSync(lst) File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Shippy/RecurringDataDump/SFDCDropboxUpload.py", line 26, in SFDCDropboxSync 
    pkl = self.SaveListtoPickle(lst) File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Shippy/RecurringDataDump/SFDCDropboxUpload.py", line 20, in SaveListtoPickle 
    pickle.dump(lst,open(f,'wb')) TypeError: coercing to Unicode: need string or buffer, instance found [Finished in 0.7s with exit code 1] [shell_cmd: python -u "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Shippy/RecurringDataDump/SFDCDropboxUpload.py"] [dir: /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Shippy/RecurringDataDump] [path: /usr/bin:/bin:/usr/sbin:/sbin] 

Answer 1

在你的代碼中，NamedTemporaryFile f不是一個字符串。它是一個文件對象，與open（file_path）的輸出類似。

從documentation：這個類文件對象可以在with語句中使用，就像普通文件一樣。

如果你想路徑創建的文件，使用tmp_file.name

例如，這個工程：（Python的3.6.2測試）

def SFDCDropboxSync(Data): 
    with tempfile.NamedTemporaryFile() as tmp_file: 
     pickle.dump(Data, tmp_file) 
     tmp_file.flush() 

     print(pickle.load(open(tmp_file.name, 'rb'))) 

這將刪除文件時，它退出while（文件關閉）。

對Windows的警告：在打開文件時可能會遇到問題。相反，使用類似的東西：

with tempfile.NamedTemporaryFile(delete=False) as tmp_file: 
    pickle.dump(Data, open(tmp_file.name, 'wb')) 
    tmp_filename = tmp_file.name 

pickle.load(open(tmp_filename, 'rb')) 
os.remove(tmp_filename)