j2cli - Jinja2 Command-Line Tool

j2cli is a command-line tool for templating in shell-scripts, leveraging the Jinja2 library.

Installation

pip install j2cli

Usage

Compile a template using INI-file data source:

$ j2 config.j2 data.ini

Compile using JSON data source:

$ j2 config.j2 data.json

Compile using YAML data source (requires PyYAML):

$ j2 config.j2 data.yaml

Compile using JSON data on stdin:

$ curl http://example.com/service.json | j2 --format=json config.j2

Compile using environment variables (hello Docker!):

$ j2 config.j2

Or even read environment variables from a file:

$ j2 --format=env config.j2 data.env

Reference

j2 accepts the following arguments:

• template: Jinja2 template file to render
• data: (optional) path to the data used for rendering. The default is -: use stdin

Options:

• --format, -f: format for the data file. The default is ?: guess from file extension.

There is some special behavior with environment variables:

• When data is not provided (data is -), --format defaults to env and thus reads environment variables
• When --format=env, it can read a special "environment variables" file made like this: env > /tmp/file.env

Formats: --format

ini

data.ini:

[nginx]
hostname=localhost
webroot=/var/www/project
logs=/var/log/nginx/

Usage:

$ j2 config.j2 data.ini
$ cat data.ini | j2 --format=ini config.j2

json

data.json:

{
    "nginx":{
        "hostname": "localhost",
        "webroot": "/var/www/project",
        "logs": "/var/log/nginx/"
    }
}

Usage:

$ j2 config.j2 data.json
$ cat data.json | j2 --format=ini config.j2

yaml

data.yaml:

nginx:
  hostname: localhost
  webroot: /var/www/project
  logs: /var/log/nginx

Usage:

$ j2 config.j2 data.yml
$ cat data.yml | j2 --format=yaml config.j2

env

Render directly from environment variable values:

$ j2 config.j2

Or read them from a file:

NGINX_HOSTNAME=localhost
NGINX_WEBROOT=/var/www/project
NGINX_LOGS=/var/log/nginx/

And render with:

$ j2 config.j2 data.env
$ env | j2 --format=env config.j2.