How to make a date picker that does not select previous dates in Django-CodePudding

I want to make a date picker that does not select previous dates using Django.

class DateInput(forms.DateInput):
    input_type = 'date'

class TimeInput(forms.TimeInput):
    input_type = 'time'
"""class used for booking a time slot."""
class BookingForm(forms.ModelForm):
    class Meta:
        model = Booking
        fields = ['check_in_date', 'check_in_time', 'check_out_time',
                    'person', 'no_of_rooms']

        widgets = {
                    'check_in_date': DateInput(),
                    'check_in_time': TimeInput(),
                    'check_out_time': TimeInput(),
                }

    """Function to ensure that booking is done for future and check out is after check in"""
    def clean(self):
        cleaned_data = super().clean()
        normal_book_date = cleaned_data.get("check_in_date")
        normal_check_in = cleaned_data.get("check_in_time")
        normal_check_out_time = cleaned_data.get("check_out_time")
        str_check_in = str(normal_check_in)
        format = '%H:%M:%S'
        try:
            datetime.datetime.strptime(str_check_in, format).time()
        except Exception:
            raise ValidationError(
                _('Wrong time entered.'),
                code='Wrong time entered.',
            )


        # now is the date and time on which the user is booking.
        now = timezone.now()
        if (normal_book_date < now.date() or
            (normal_book_date == now.date() and
            normal_check_in < now.time())):
            raise ValidationError(
                "You can only book for future.", code='only book for future'
            )
        if normal_check_out_time <= normal_check_in:
            raise ValidationError(
                "Check out should be after check in.", code='check out after check in'
            )

The above code is written in forms.py file. As you can see, I made a date picker but the problem is that the user can select any date but I want him to select only current or future dates. Perhaps, it can be done using JavaScript or bootstrap but I want to know can we do it in Django?

CodePudding user response：

Django is a web framework that allows you to create dynamic web applications using Python. One of the features that Django provides is the ability to create forms that can validate user input and display errors. You can also use widgets to customize the appearance and behavior of the form fields.

One of the widgets that Django offers is the DateInput widget, which renders a text input field that can be attached to a date picker using JavaScript. However, by default, the date picker does not restrict the user from selecting previous dates, which might not be desirable for some applications.

To make a date picker that does not select previous dates using Django, you need to do the following steps:

Step 1: Install a JavaScript library that provides a date picker

There are many JavaScript libraries that can provide a date picker functionality, such as jQuery UI, Bootstrap Datepicker, or Flatpickr. You can choose any of them according to your preference and compatibility with your project. For this example, we will use Flatpickr, which is a lightweight and customizable date picker library.

To install Flatpickr, you can use a package manager like npm or yarn, or you can download the files from the official website and include them in your project. You will need to include the flatpickr.min.js and flatpickr.min.css files in your HTML template.

Step 2: Create a custom widget that inherits from DateInput and adds the Flatpickr attributes

To use Flatpickr with Django, you need to create a custom widget that inherits from the DateInput widget and adds the necessary attributes to the input field. The attributes are:

data-toggle: This tells Flatpickr to attach itself to the input field.
data-min-date: This tells Flatpickr the minimum date that can be selected. You can use a fixed date or a dynamic date based on the current date. For example, "today" means the user can only select today or future dates.
data-date-format: This tells Flatpickr the format of the date that will be displayed and submitted. You can use any format that is supported by Flatpickr, but make sure it matches the format that Django expects. For example, "%Y-%m-%d" means the date will be in the format of year-month-day.

The custom widget can be defined as follows:

from django.forms import DateInput

class FlatpickrDateInput(DateInput):
    def __init__(self, *args, **kwargs):
        # You can pass any additional options to Flatpickr as keyword arguments
        self.options = kwargs.pop('options', {})
        super().__init__(*args, **kwargs)

    def build_attrs(self, base_attrs, extra_attrs=None):
        # Add the Flatpickr attributes to the input field
        attrs = super().build_attrs(base_attrs, extra_attrs)
        attrs['data-toggle'] = 'flatpickr'
        attrs['data-min-date'] = self.options.get('min_date', 'today')
        attrs['data-date-format'] = self.options.get('date_format', '%Y-%m-%d')
        return attrs

Step 3: Use the custom widget in your form field

To use the custom widget in your form field, you need to pass it as the widget argument when defining the field. For example, if you have a model that has a date field, you can create a model form that uses the custom widget as follows:

from django import forms
from .models import MyModel
from .widgets import FlatpickrDateInput

class MyModelForm(forms.ModelForm):
    class Meta:
        model = MyModel
        fields = ['date']
        widgets = {
            'date': FlatpickrDateInput(options={'date_format': '%d/%m/%Y'})
        }

Step 4: Render the form in your template and initialize Flatpickr

To render the form in your template, you can use the standard Django template tags, such as {{ form }} or {{ form.date }}. You also need to include the Flatpickr files and initialize the library by calling the flatpickr function on the input fields that have the data-toggle attribute. For example, your template could look like this:

<html>
<head>
    <!-- Include the Flatpickr files -->
    <link rel="stylesheet" href="flatpickr.min.css">
    <script src="flatpickr.min.js"></script>
</head>
<body>
    <!-- Render the form -->
    <form method="post">
        {% csrf_token %}
        {{ form }}
        <input type="submit" value="Submit">
    </form>

    <!-- Initialize Flatpickr -->
    <script>
        // Select all the input fields that have the data-toggle attribute
        var dateInputs = document.querySelectorAll('[data-toggle="flatpickr"]');
        // Call the flatpickr function on each input field
        dateInputs.forEach(function(input) {
            flatpickr(input);
        });
    </script>
</body>
</html>

Conclusion

By following these steps, you can make a date picker that does not select previous dates using Django and Flatpickr. This can improve the user experience and the data validation of your web application. You can also customize the date picker further by using other options and methods that Flatpickr provides. You can find more information and examples on the official documentation of Flatpickr: https://flatpickr.js.org/

CodePudding user response：

You can specify a min attribute ^[mdn-doc] for the date input type:

from django.utils.timezone import now


class FutureDateInput(forms.DateInput):
    input_type = 'date'

    def get_context(self, name, value, attrs):
        attrs.setdefault('min', now().strftime('%Y-%m-%d'))
        return super().get_context(name, value, attrs)

You will need to do validation in the form/model, since this will only limit this at the client side.