Easy template rendering with Python

There were some cases I want to render some template file easily without any rendering engine(such as ERB, jade). So far I wrote some script which uses sed command to replace an arbitrary placeholder written by myself. This is a little tough work and not maintainable. I have found a easy way to render an template file with only Python.

Python has already original format print method. You might see it.

>>> vars = {"yourname":"Nobita", "myname":"Kai"}
>>> print("Hello, %(yourname)s" % d)
Hello, Nobita

We can use this method for rendering template file. Your template.txt file can be like this.

Hello, %(yourname)s, my name is %(myname)s. Nice to meet you!

In python script, your can write below code to replace all placeholders.

#!/usr/bin/env python

# This is given from other place.
vars = {
  "yourname": "Takeshi", "myname": "Kai"
}

with open("./template.txt") as f:
    data = f.read()
    print(data % vars)

OK. We can obtain desired output from this script.

Hello, Takeshi, my name is Kai. Nice to meet you!

When you put template file with rendering such as configuration files, you can use this way. Thank you.