more code cleanup & added 'exclude filenames' from hashing

utils/inspector.py

@@ -6,21 +6,41 @@ import pandas as pd
 
 CSV_DIR = os.path.join(os.getcwd(), 'csv')
 
-def get_hashes_in_dir(dir_path: str) -> list:
+
+def load_excluded_filenames(submissions_dir_name: str) -> list[str]:  # helper function for hashing all files
+    csv_file_path = os.path.join(CSV_DIR, f'{submissions_dir_name}_excluded.csv')
+    if not os.path.exists(csv_file_path):  # if csv file with excluded file names for submission does not exist
+        print(f'[WARNING] Cannot find CSV file with list of excluded file names: {csv_file_path}\n[INFO] All files will be hashed & inspected')
+        return []  # return empty list to continue without any excluded file names
+    else:  # if csv file with excluded file names for submission exists
+        try:            
+            df = pd.read_csv(csv_file_path)
+            filename_list = df['exclude_filename'].tolist()  # get the values of the 'filename' column as a list
+            print(f'[INFO] Using CSV file with list of excluded file names: {csv_file_path}')
+            return filename_list
+        except Exception as e:  # any exception, print error and return empty list to continue without any excluded file names
+            print(f'[WARNING] Unable to load / read CSV file with list of excluded file names: {csv_file_path}\n[INFO] All files will be hashed & inspected')
+            print(f'[INFO] Error message: {e}')
+            return []
+
+
+def get_hashes_in_dir(dir_path: str, excluded_filenames: list = []) -> list:  # helper function for hashing all files
     hash_list = []
     for subdir, dirs, files in os.walk(dir_path):  # loop through all files in the directory and generate hashes
-        for file in files:
-            filepath = os.path.join(subdir, file)
-            with open(filepath, 'rb') as f:
-                filehash = hashlib.sha256(f.read()).hexdigest()
-                hash_list.append({ 'filepath': filepath, 'filename': file, 'sha256 hash': filehash})
+        for filename in files:
+            if filename not in excluded_filenames:  # do not hash for inspection file names in the excluded list
+                filepath = os.path.join(subdir, filename)
+                with open(filepath, 'rb') as f:
+                    filehash = hashlib.sha256(f.read()).hexdigest()
+                    hash_list.append({ 'filepath': filepath, 'filename': filename, 'sha256 hash': filehash})
     return hash_list
 
 
-def hash_submissions(submissions_dir_path: str) -> str:
+def hash_submissions(submissions_dir_path: str) -> str:  # main function for hashing all files
     os.makedirs(CSV_DIR, exist_ok=True)
-
     submissions_dir_name = os.path.abspath(submissions_dir_path).split(os.path.sep)[-1]  # get name of submission/assignment by separating path and use rightmost part
+    excluded_filenames = load_excluded_filenames(submissions_dir_name)
+
     csv_file_name = f'{submissions_dir_name}_file_hashes_{datetime.now().strftime("%Y%m%d-%H%M%S")}.csv'
     csv_file_path = os.path.join(CSV_DIR, csv_file_name)
     with open(csv_file_path, 'w', newline='') as csvfile:  # open the output CSV file for writing
@@ -30,28 +50,30 @@ def hash_submissions(submissions_dir_path: str) -> str:
 
         for student_dir_name in os.listdir(submissions_dir_path):  # loop through each student dir to get hashes for all files per student
             student_dir_path = os.path.join(submissions_dir_path, student_dir_name)
-            hashes_dict = get_hashes_in_dir(student_dir_path)  # dict with hashes for all student files 
+            hashes_dict = get_hashes_in_dir(student_dir_path, excluded_filenames)  # dict with hashes for all student files - except for 'excluded' file names
             for d in hashes_dict:
                 d.update({'Student ID': student_dir_name})  # update hash records with student id
             writer.writerows(hashes_dict)
     print(f'[INFO] Created CSV file with all files & hashes in {submissions_dir_name}\nCSV file: {csv_file_path}')
     return csv_file_path
+   
 
-
-def get_suspicious_hashes(df: pd.DataFrame) -> list:
+def inspect_for_duplicate_hashes(hashes_csv_file_path: str):  # main function for finding duplicate / suspicious hashes
+    csv = pd.read_csv(hashes_csv_file_path)
+    df = pd.DataFrame(csv)  # df with all files and their hashes
     drop_columns = ['filepath', 'filename']  # only need to keep 'student id' and 'sha256 hash' for groupby later
-    df = df.drop(columns=drop_columns).sort_values('sha256 hash')  # clear not needed colums & sort by hash
+    df = df.drop(columns=drop_columns)  # clear not needed columns
     duplicate_hash = df.loc[df.duplicated(subset=['sha256 hash'], keep=False), :]  # all files with duplicate hash - incl. files from the same student id
-
     hash_with_multiple_student_ids = duplicate_hash.groupby('sha256 hash').agg(lambda x: len(x.unique())>1)  # true if more than 1 unique student ids (= files with the same hash by multiple student ids), false if unique student id (= files from the same student id with the same hash)
-
     suspicious_hashes_list = hash_with_multiple_student_ids[hash_with_multiple_student_ids['Student ID']==True].index.to_list()  # list with duplicate hashes - only if different student id (doesn't include files from same student id)
-    return suspicious_hashes_list  
+    files_with_suspicious_hash = df[df['sha256 hash'].isin(suspicious_hashes_list)]  # df with all files with duplicate/suspicious hash, excludes files from the same student id
+    df_suspicious = files_with_suspicious_hash.sort_values(['sha256 hash', 'Student ID'])  # sort before output to csv
+    
+    try:
+        submissions_dir_name = os.path.basename(hashes_csv_file_path).split('_file_hashes_')[0]
+        csv_out = hashes_csv_file_path.rsplit('_', 1)[0].replace('file_hashes', 'suspicious_') + datetime.now().strftime("%Y%m%d-%H%M%S") + '.csv'
+        df_suspicious.to_csv(csv_out, index=False)
+        print(f'[INFO] Created CSV file with duplicate/suspicious hashes in {submissions_dir_name}\nCSV file: {csv_out}')
+    except Exception as e:
+        exit(f'[ERROR] Something went wrong while trying to save csv file with suspicious hashes\nError message: {e}')
 
-
-def suspicious_by_hash(df: pd.DataFrame) -> pd.DataFrame:
-    suspicious_hashes_list = get_suspicious_hashes(df)
-
-    files_with_suspicious_hash = df[df['sha256 hash'].isin(suspicious_hashes_list)]  # excluding duplicate from same student id
-    return files_with_suspicious_hash.sort_values(['sha256 hash', 'Student ID'])
-