Single DateTimePicker

Date time picker form element using the xdan jQuery Plugin Date and Time Picker library - https://github.com/xdan/datetimepicker.

It supports date/time and date fields. You can use it on Datetime and Datetime Range fields.

MODULE INSTALLATION

Install the Drupal module as usual. Visit https://www.drupal.org/node/1897420 for further information.

LIBRARY INSTALLATION

For this module to be operational you need to install 3rd party plugin (DateTimePicker - jQuery plugin select date and time). You can do it manually or through the composer.

Manual:
Download xdan library from github: https://github.com/xdan/datetimepicker/archive/2.5.20.zip
Extract and then copy the entire folder inside libraries. (folder should be named datetimepicker)

Composer:
This method requires basic knowledge of Composer and changes on your project composer.json (not this module composer.json file).

While Drupal 8 does not have still an easy way to handle external dependencies still, I recommend the usage of a composer package called drupal-libraries-installer.

Libraries need to be defined in composer.json like the example below:

"extra": {
    "drupal-libraries": {
        "datetimepicker": "https://github.com/xdan/datetimepicker/archive/2.5.20.zip"
     },
}

Ensure composer packages of type drupal-library are configured to install to the appropriate path.
Read more at https://github.com/zodiacmedia/drupal-libraries-installer

More about handling 3rd party libraries:
Drupal core should help make 3rd party library management not torturous

USAGE

On content type go under “Manage form display” and
for date field select Single Date Time Picker.

FEATURES

• Support Datetime and Datetime Range field types
• 12/24 hour format display
• Option to choose granularity for minutes
• Option to disable specific days global (etc. Saturday)
• Option to disable specific dates, useful for holidays, working days, etc..
• Choose between light and black theme
• Display date and time picker inline