Rename files with Python by dynamically adding numbering

Question

I have a directory with many pdf lists, and want to rename the files dynamically.

Ex:

~/teste/

|__ProjMed-Química-Físico.Química-quimica_propriedades_coligativas_exercicios.pdf

|__ProjMed-Química-Físico.Química-quimica_termoquimica_entalpia_lei_de_hess_energia_de_ligacao_exercicios_gabarito.pdf

So far, my code is like this:

import os
os.chdir('/home/matheus/teste/')
for f in os.listdir():
    f_name, f_ext = os.path.splitext(f)
    f_id, f_subject, f_frente, f_topic = f_name.split('-')
    f_name1 = '{}-{}-{}-{}{}'.format(f_id, f_subject, f_frente, f_topic, f_ext)
    print(f_name1)
# print(sorted(f_name1, key=str))

as can be seen in f_id, there will always be a repeated identifier. in the case of the example, 'Projmed'.

i would like to count how many Projmed appear (total files with this identifier) and rename them so that it gets something like this:

1-Projmed-***

2-Projmed-***

3-Projmed-***

etc...

I am trying to make a script that runs every time a new file is added to a folder. (would be activated with the incron, Linux) then, on a day-to-day basis, there will be some files that already have a numbering and others that should still have the numbering added (always 1 more than the highest value already present in another file). Logically, if there is already a file with numbering, it should be ignored in renaming.

how could I modify my current script to achieve these goals?

• Count how many 'identifiers' appear per folder ('Projmed', for example)
• ignore renaming files that already have numbering
• rename files without numbering with n+1, being n the largest number present in a file in this folder

Answer 1

Hello,

follows a proposal for solution to your problem.

To facilitate mainly the file appointment was made the following class:

class fileDataModel:
    def __init__(self, id_name, subject, frente, topic, ext, id_num = 0):
        self.id_num = id_num
        self.id_name = id_name
        self.subject = subject
        self.frente = frente
        self.topic = topic
        self.ext = ext

    def __repr__(self):
        return self.getFileName()

    def getFileName(self):
        if self.id_num != 0:
            return "{}-{}-{}-{}-{}{}".format(self.id_num, self.id_name, self.subject, self.frente, self.topic, self.ext)
        return "{}-{}-{}-{}{}".format(self.id_name, self.subject, self.frente, self.topic, self.ext)

Note that the method getFileName returns different strings depending on the value of id_num. It was considered that when the id_num is equal to 0, the file is new and does not yet have numbering.

Now follows a proposal for automatic numbering of new files:

import os

os.chdir('/home/matheus/teste/')

files = dict()
for f in os.listdir():
    f_name, f_ext = os.path.splitext(f)
    f_name = f_name.split('-')

    f_id_num = 0

    if len(f_name) == 4: # Arquivo sem identificador
        f_id, f_subject, f_frente, f_topic = f_name
    elif len(f_name) == 5: # Arquivo ja com identificador
        f_id_num, f_id, f_subject, f_frente, f_topic = f_name
        f_id_num = int(f_id_num)
    else:
        print(f"Arquivo com nome fora do padrao: {f}")
        continue

    newFileDataModel = fileDataModel(f_id, f_subject, f_frente, f_topic, f_ext, f_id_num)

    if f_id not in files.keys():
        files[f_id] = {'last_id' : f_id_num, 'files' : [newFileDataModel]}
    else:
        files[f_id]['files'].append(newFileDataModel)
        if f_id_num > files[f_id]['last_id']:
            files[f_id]['last_id'] = f_id_num

for key in files.keys():

    last_id = files[key]['last_id']

    for file in files[key]['files']:
        if file.id_num != 0:
            continue

        last_id += 1

        old_file_name = file.getFileName()
        file.id_num = last_id

        os.rename(old_file_name, file.getFileName())

Note that the above code always considers the highest id present in the added files. That is, if the highest id is 4, a new file will have id equal to 5. Also, if there is deletion of any file with id less than the highest id, a new file added will not be contemplated with that missing id in the sequence but with a number more than the highest id present.