Jinja2 templating with Docker

Docker Hub

Docker Hub Image

Github docker image

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Github Docker Image as package

Steps to use

• Mount the directory containing your template(s) to the container's /templates directory
• Mount the directory containing your variables file(s) directory /variables
• Pass needed env vars (any number)
• In your jinja2 template get OS environment variables plus your inserted environment vars with environ('your_env_var')

Supported formats (default)

• YAML
• JSON
• XML
• TOML
• HJSON
• JSON5

Check jinja2-cli commands for all supported formats.

Syntax

docker run --rm \
-v **TEMPLATE_FOLDER**:/templates \ 
-v **VARIABLES_FOLDER**:/variables  \
-e CUSTOM_ENV_VAR=**VALUE** \
dinutac/jinja2docker:latest /templates/json.j2 /variables/json.json --format=json > **OUTPUT_FILE**

Example 1:

docker run --rm \
-v $PWD/inputs/templates:/templates \
-v $PWD/inputs/variables:/variables \
-e DATABASE=mysql56 -e IMAGE=latest \
dinutac/jinja2docker:latest /templates/standalone.j2 /variables/variables.yml --format=yaml > docker-compose.yml

Example 2:

docker run --rm \
-v $PWD/inputs/templates:/templates \
-v $PWD/inputs/variables:/variables \
dinutac/jinja2docker:latest /templates/json.j2 /variables/json.json --format=json

Templating example

template.json

Os: {{os}}
Flavour: {{flavour}}
   
Path: {{environ('PATH')}}

variables.json

{
  "os" : "Linux",
  "flavour": "CentOS"
}

Templating result

result.json

Os: Linux
Flavour: CentOS

Path: /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin