Py 文件MD5计算的一种方式

之前下载国家优课的文件(包含 txt,pdf,m3u8等)

为了防止文件出现重复下载，于是写了一个文件md5的获取方式

import binascii

import os

import hashlib

import shutil

def file_movie(path,move_path):

    shutil.move(path, move_path)

def str_16(s):

    str_ = binascii.b2a_hex(str(s).encode('utf-8'))

    return str_

def getHashCode(md5):

    seed = 131

    hash = 0

    bitarray = [i for i in md5]

    count = len(bitarray)

    while count>0:

        hash = hash * seed + int(ord(bitarray[len(bitarray)-count]))

        count-=1

    return (hash & 0x7FFFFFFF)

def getHashPath(md5):

    if len(md5)==32:

        hashcode1 = getHashCode(md5[0:16])

        hashcode2 = getHashCode(md5[16:32])

        dir1 = str(hex(hashcode1 & 0xff)).ljust(2,'0').replace('0x','')

        dir2 = str(hex(hashcode2 & 0xff)).ljust(2,'0').replace('0x','')

        path = "/" + dir1 + "/" + dir2 + "/"

        return path

def get_md5_id(id):

    hash_md5 = hashlib.md5()

    hash_md5.update(id)

    id = hash_md5.hexdigest()

    return id

def get_md5_str(id):

    hmac = hashlib.md5(id.encode(encoding='UTF-8')).hexdigest()

    return hmac

def get_big_file_md5(ip_file_path,ip_read_start,ip_read_len):

  with open(ip_file_path, 'rb') as f:

    f.seek(int(ip_read_start),1)

    context = get_md5_id(bytearray(f.read(ip_read_len)))

    f.close()

    return context

def get_file(dow_path):

    filesize = os.path.getsize(dow_path)

    return filesize

def get_file_md5(dow_path):

    print(dow_path)

    file_size = round(os.path.getsize(dow_path) / float(1024 * 1024), 2)

    if file_size < 28:

        with open(dow_path, 'rb') as f:

            md5obj = hashlib.md5()

            md5obj.update(f.read())

            hash = md5obj.hexdigest()

            return hash

    else:

        iStart = 0

        partLength = 16 * 1024 * 1024

        md5_one = get_big_file_md5(dow_path,iStart,partLength)

        iMidllePost = int(get_file(dow_path)/2)

        iHalfPartLength = int(partLength/2)

        iStart = iMidllePost - iHalfPartLength

        md5_two = get_big_file_md5(dow_path,iStart,partLength)

        iStart = int(get_file(dow_path)) - partLength

        md5_three = get_big_file_md5(dow_path,iStart,partLength)

        all_md5 = (md5_one + md5_two + md5_three).upper()

        all_md5 = get_md5_str(all_md5).lower()

        return all_md5

def file_name_mode_modify(file_path,file_name,info_dict):

    file_path_split = file_path.split('\\')

    file_name_split = file_path_split[-1].split('.')

    file_name_split[0] = file_name

    n = ''

    for i in file_path_split[:-1]:

        n+=i+"\\"

    n+=  file_name_split[0]+'.'+file_name_split[1]

    os.rename(file_path,n)

    info_dict['new_file_ml'] = n

    return info_dict