python-patterns/patterns/behavioral/template.py at master · Androidown/python-patterns · GitHub

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#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
An example of the Template pattern in Python

*TL;DR
Defines the skeleton of a base algorithm, deferring definition of exact
steps to subclasses.

*Examples in Python ecosystem:
Django class based views: https://docs.djangoproject.com/en/2.1/topics/class-based-views/
"""


defget_text():
return"plain-text"


defget_pdf():
return"pdf"


defget_csv():
return"csv"


defconvert_to_text(data):
print("[CONVERT]")
return"{} as text".format(data)


defsaver():
print("[SAVE]")


deftemplate_function(getter, converter=False, to_save=False):
data=getter()
print("Got `{}`".format(data))

iflen(data) <=3andconverter:
data=converter(data)
else:
print("Skip conversion")

ifto_save:
saver()

print("`{}` was processed".format(data))


defmain():
"""
 >>> template_function(get_text, to_save=True)
 Got `plain-text`
 Skip conversion
 [SAVE]
 `plain-text` was processed

 >>> template_function(get_pdf, converter=convert_to_text)
 Got `pdf`
 [CONVERT]
 `pdf as text` was processed

 >>> template_function(get_csv, to_save=True)
 Got `csv`
 Skip conversion
 [SAVE]
 `csv` was processed
 """


if__name__=="__main__":
importdoctest
doctest.testmod()