j2render - Python script to render Jinja2 templates on the CLI

j2render.py

#!/usr/local/bin/python

# To get all dependencies for this, run:
# pip install PyYAML jinja2

# To install, just copy it to /usr/local/bin.

import sys, os
import jinja2
import yaml

def render(tpl_path, context):
    path, filename = os.path.split(tpl_path)
    return jinja2.Environment(
        loader=jinja2.FileSystemLoader(path or './')
    ).get_template(filename).render(context)

def usage():
    print(" j2render - Simple Jinja2 renderer \n")
    print("Usage:\n")
    print("j2render <template.anything> <context.yml> [-o | output.anything]\n")
    print("Options:")
    print(" -o: Print results directly to stdout, rather than writing to a file.")
    sys.exit(1)

try:
    if "-o" in sys.argv:
        sys.argv.remove("-o")
        print_to_term = True
    else:
        print_to_term = False

    context = open(sys.argv[2], 'r')
    context = yaml.load(context)

    result = render(sys.argv[1], context)

    if not print_to_term:
        f = open(sys.argv[3], 'w')
        f.write(result)
        f.close()
    else:
        print(result)

except IndexError:
    print("Missing an argument!")
    usage()
except Exception as e:
    print("An unexpected error occurred: " + str(e))
    usage()