Python: Append Template String to New File

Reads and Appends File Objects, then Opens File in Gedit

Shebang/Interpreter Directive

#!/usr/bin/env python3

Import os.system

from os import system

Path: Working Directory

PATH = '/home/foo/Documents/html/'

Input Filename

User prompted to enter name of file. .html is automatically filled in. In this example, the text string foo will be assigned to the fi variable.

fi = input('Fill in the blank ________.html: ')

Template Text Stream

open() function creates a file object for reading only, when the 'r' parameter is passed to it. The template file path /home/foo/Documents/html/_template.html is assigned to the name parameter. read mode and UTF-8 encoding are defaults.

<_io.TextIOWrapper name='/home/foo/Documents/html/_template.html' mode='r' encoding='UTF-8'>

tr = open(PATH + '_template.html', 'r')

Template String

read() method reads the file object assigned to tr and returns a string.

ts = tr.read()

New File Text Stream

Passing the 'a' parameter to the open() function creates a file object for appending only. The new file’s path /home/foo/Documents/html/foo.html is assigned to the name parameter. UTF-8 encoding is a default. Since the template string from _template.html will be appended to foo.html using the write() function.

<_io.TextIOWrapper name='/home/foo/Documents/html/foo.html' mode='a' encoding='UTF-8'>

The following try…finally block ensures file closure:

try:
    nf = open(PATH + fi + '.html', 'a')
    nf.write(ts)
finally:
    nf.close()

System

os.system executes commands in the subshell:

• chown 1000:1000 /home/foo/Documents/html/foo.html
• chmod 755 /home/foo/Documents/html/foo.html₁
• gedit /home/foo/Documents/html/foo.html

system('chown 1000:1000 ' + PATH + fi + '.html')
system('chmod 755 ' + PATH + fi + '.html')
system('gedit ' + PATH + fi + '.html')

₁. 644 and 755 are standard Unix permissions settings.