How to rename files in directory with its sha1 hash with python?

Question

I need to rename my files in directory with its hash with Python. I've done the same thing using C#:

   Console.Write("enter path");
        string path = Console.ReadLine();

        foreach (var i in Directory.GetFiles(path))
        {
            try
            {
                using (SHA1Managed sha1 = new SHA1Managed())
                {
                    FileStream f = new FileStream(i.ToString(), FileMode.Open);
                    byte[] hash = sha1.ComputeHash(f);
                    string formatted = string.Empty;
                    foreach (byte b in hash)
                    {
                        formatted += b.ToString("X2");
                    }
                    f.Close();

                    File.Move(i.ToString(), path+"//" + formatted);
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(i.ToString());
            }

Can someone help me get started with what I'd use in Python to accomplish the same? I'll be using Ubuntu, if it makes any difference.

Answer 1

In Python if you want to compute some hash (MD5, SHA1) there is hashlib module. To make some operations on filesystem there is os module. In those modules you will find: sha1 object with hexdigest() method and listdir() and rename() functions. Example code:

import os
import hashlib

def sha1_file(fn):
    f = open(fn, 'rb')
    r = hashlib.sha1(f.read()).hexdigest()
    f.close()
    return r

for fn in os.listdir('.'):
    if fn.endswith('.sha'):
        hexh = sha1_file(fn)
        print('%s -> %s' % (fn, hexh))
        os.rename(fn, hexh)

Attention : sha1_file() function read whole file at once so it will not work very well for huge files. As a homework try to improve it for such files (read file in parts and update hash with those parts).

Of course if fn.endswith('.sha'): is used for test purposes only.