In this article, we will code a python script to find duplicate files in the file system or inside a particular folder.
Method 1: Using Filecmp
The python module filecmp offers functions to compare directories and files. The cmp function compares the files and returns True if they appear identical otherwise False.
Syntax: filecmp.cmp(f1, f2, shallow)
Parameters:
- f1: Name of one file
- f2: Name of another file to be compared
- shallow: With this, we set if we want to compare content or not.
Note: The default value is True which ensures that only the signature of files is compared not content.
Return Type: Boolean value (True if the files are same otherwise False)
Example:
We’re assuming here for example purposes that “text_1.txt”, “text_3.txt”, “text_4.txt” are files having the same content, and “text_2.txt”, “text_5.txt” are files having the same content.
Python3
# Importing Libraries import os from pathlib import Path from filecmp import cmp # list of all documents DATA_DIR = Path('/path/to/directory') files = sorted(os.listdir(DATA_DIR)) # List having the classes of documents # with the same content duplicateFiles = [] # comparison of the documents for file_x in files: if_dupl = False for class_ in duplicateFiles: # Comparing files having same content using cmp() # class_[0] represents a class having same content if_dupl = cmp( DATA_DIR / file_x, DATA_DIR / class_[0], shallow=False ) if if_dupl: class_.append(file_x) break if not if_dupl: duplicateFiles.append([file_x]) # Print results print(duplicateFiles) |
Output:
Method 2: Using Hashing and Dictionary
To start, this script will get a single folder or a list of folders, then through traversing the folder it will find duplicate files. Next, this script will compute a hash for every file present in the folder regardless of their name and are stored in a dictionary manner with hash being the key and path to the file as value.
- We have to import os, sys, hashlib libraries.
- Then script iterates over the files and calls FindDuplicate() function to find duplicates.
Syntax: FindDuplicate(Path) Parameter: Path: Path to folder having files Return Type: Dictionary
- The function FindDuplicate() takes path to file and calls Hash_File() function
- Then Hash_File() function is used to return HEXdigest of that file. For more info on HEXdigest read here.
Syntax: Hash_File(path) Parameters: path: Path of file Return Type: HEXdigest of file
- This MD5 Hash is then appended to a dictionary as key with file path as its value. After this,the FindDuplicate() function returns a dictionary in which keys has multiple values .i.e. duplicate files.
- Now Join_Dictionary() function is called which joins the dictionary returned by FindDuplicate() and an empty dictionary.
Syntax: Join_Dictionary(dict1,dict2) Parameters: dict1, dict2: Two different dictionaries Return Type: Dictionary
- After this, we print the list of files having the same content using results.
Example:
We’re assuming here for example purposes that “text_1.txt”, “text_3.txt”, “text_4.txt” are files having the same content, and “text_2.txt”, “text_5.txt” are files having the same content.
Python3
# Importing Libraries import os import sys from pathlib import Path import hashlib def FindDuplicate(SupFolder): # Duplic is in format {hash:[names]} Duplic = {} for file_name in files: # Path to the file path = os.path.join(folders, file_name) # Calculate hash file_hash = Hash_File(path) # Add or append the file path to Duplic if file_hash in Duplic: Duplic[file_hash].append(file_name) else: Duplic[file_hash] = [file_name] return Duplic # Joins dictionaries def Join_Dictionary(dict_1, dict_2): for key in dict_2.keys(): # Checks for existing key if key in dict_1: # If present Append dict_1[key] = dict_1[key] + dict_2[key] else: # Otherwise Stores dict_1[key] = dict_2[key] # Calculates MD5 hash of file # Returns HEX digest of file def Hash_File(path): # Opening file in afile afile = open(path, 'rb') hasher = hashlib.md5() blocksize=65536 buf = afile.read(blocksize) while len(buf) > 0: hasher.update(buf) buf = afile.read(blocksize) afile.close() return hasher.hexdigest() Duplic = {} folders = Path('path/to/directory') files = sorted(os.listdir(folders)) for i in files: # Iterate over the files # Find the duplicated files # Append them to the Duplic Join_Dictionary(Duplic, FindDuplicate(i)) # Results store a list of Duplic values results = list(filter(lambda x: len(x) > 1, Duplic.values())) if len(results) > 0: for result in results: for sub_result in result: print('\t\t%s' % sub_result) else: print('No duplicates found.') |
Output:
