time data '0:02:00' does not match format '%H %M %S'

Question

I want to save a string as time format to store it in the database for a django project, Here's my utils.py file:

import datetime
import re
import math
from django.utils.html import strip_tags

def count_words(text_string):
    word_string = strip_tags(text_string)
    matching_words = re.findall(r'\w+', word_string)
    count = len(matching_words)
    return count

def get_read_time(text_string):
    count = count_words(text_string)
    read_time_min = math.ceil(count/200.0) #Assuming 200 words per min Reading
    read_time = str(datetime.timedelta(minutes=read_time_min))
    return read_time

Here's the required portion of the models.py file:

class Post(models.Model):
    read_time = models.TimeField(null=True, blank=True)

Here's the required portion of the views.py file :

class PostDetailView(DetailView):
    model = Post

    def get_context_data(self, *args, **kwargs):
        context = super().get_context_data(**kwargs)
        texts = self.object.content
        # print(texts)
        read_time=get_read_time(texts)
        # print(read_time)
        Post.objects.create(read_time=datetime.strptime(read_time, "%H:%M:%S"))
        return context

The Output format of the string is 0:02:00 this I want to save it in the database as datetime field. But I am encountering this error:-

Exception Type: ValueError at /post/this-blog-contains-an-image-with-it/
Exception Value: 's' is a bad directive in format '%H:%MM:%ss'

Answer 1

A TimeField [Django-doc] expects a time object, not a datetime object. You can make use of the .time() method [Django-doc] to retrieve the time part:

class PostDetailView(DetailView):
    model = Post

    def get_context_data(self, *args, **kwargs):
        context = super().get_context_data(**kwargs)
        texts = self.object.content
        read_time=get_read_time(texts)
        Post.objects.create(read_time=datetime.strptime(read_time, '%H:%M:%S'))
        return context

It is however rather odd to construct a string instead of returning the timedelta part itself:

def get_read_time(text_string):
    count = count_words(text_string)
    read_time_min = math.ceil(count/200.0) #Assuming 200 words per min Reading
     datetime.timedelta(minutes=read_time_min)

Then you can use this timedelta to obtain the time:

class PostDetailView(DetailView):
    model = Post

    def get_context_data(self, *args, **kwargs):
        context = super().get_context_data(**kwargs)
        texts = self.object.content
        read_time=get_read_time(texts)
        Post.objects.create(read_time=(datetime.datetime.min + read_time).time())
        return context

It furthermore does not make sense to construct objects in the get_context_data . A GET request is supposed to have no side-effects, so you should only make database changes for POST, PUT, PATCH, DELETE, etc. requests. Not in the get_context_data .