Render Kit is a versatile and powerful command-line interface (CLI) tool designed for comprehensive template rendering. It supports multiple template engines and data sources, providing both flexibility and efficiency.

Features

• 🛠️ Supports multiple template engines
• 🌐 Integrates with various data sources
• 🎛️ Customizable rendering options
• ⚡ Lightweight and fast
• 🌍 Cross-platform compatibility
• 📦 Single binary

Supported Engines

• Envsubst
• Go Templates (including Sprig Functions)
• Handlebars
• Jet
• Jinja
• Mustache

Supported Datasources

• Environment variables
• YAML
• JSON
• TOML
• HTTP/S URL (For web URLs, ensure the response's Content-Type matches the file format's MIME type. Environment variable file types are not supported yet)

Usage

To use Render Kit, you have multiple options:

1. Download the latest release binary:

   • Visit the releases page and download the latest binary for your operating system. It's recommended to move the binary to a directory in your PATH to make it easier to run such as /usr/local/bin.

2. Install via Go:

   • Ensure that you have Go installed on your machine.
   • Run the following command:

     go install github.com/orellazri/renderkit@latest

3. Run the Docker image:

   • If you prefer using Docker, you can run the reaperberri/renderkit Docker image.
   • Make sure you have Docker installed on your machine.
   • Run the following command:

     docker run --rm reaperberri/renderkit <args>

You need to run the renderkit command with the following arguments as either command-line flags, or as a YAML configuration file passed via --config.

Name	Description	Type
config	Load configuration from YAML file	string
input	Template string to render	string
input-file	Template input file to render	string
input-dir	Template input directory to render	string
exclude	Exclude files/directories using path-based glob or file glob patterns	list
output	Output directory to write to	string
datasource	Datasource to use for rendering (scheme://path) **	list
data	Data to use for rendering. Can be used to provide data directly	list
engine	Templating engine to use for rendering (Go Templates by default)	string
allow-duplicate-keys	Allow duplicate keys in datasources. If set, the last value found will be used	bool

**Notes on datasource

• Inputs not utilizing a URL scheme (<scheme>://, etc.) will be interpreted as plain files. Refer to Supported Datasources for available formats.
• For now, only the env scheme is supported for datasources.
• Using just env:// will load all your environment variables as keys you can use in your templates.
• Using env://<env_var> will load only that specific environment variable.
• Specifying a path like path/to/myvars.env will load the variables from an .env file (the file must have a .env suffix).

Below are practical examples demonstrating the usage of renderkit:

# Using a specific env var as a datasource
$ cat ds.yml
FN: "Doe"
$ echo 'Hello {{.FN}} {{.LN}}' | renderkit -ds env://LN -ds ds.yml
Hello John Doe

# Using a template string and envsubst engine
$ export LN="Doe"
$ echo 'Hello $FN $LN' | renderkit -i 'Hello $FN $LN' -e envsubst --data "FN=John"
Hello John Doe

# Using a template file with data from a JSON file
$ cat data.json
{
  "names": {
    "FN": "John",
    "LN": "Doe"
  }
}
$ cat file.tpl
Hello {{ lower .names.FN }} {{ upper .names.LN }}
$ renderkit -f file.tpl -ds data.json
Hello john DOE

# Render input directory [1.tpl, 2.tpl, 3.tpl] to output directory
$ renderkit --input-dir in/ --exclude 'in/[1-2].tpl' --output out/ --datasource data.yml --data myKey=myValue --engine jinja
# Output directory will contain [3.tpl] rendered files

# Use the two supported exclude patterns (path-based Render input directory [1.tpl, 2.tpl, 3.tpl, 1.txt] to output directory
$ renderkit --input-dir in/ --exclude 'in/[1-2].tpl' --exclude '*.txt' --datasource data.yml
# Output directory will contain [3.tpl] rendered files

Example YAML Configuration File

input-dir: input/
output: output/
exclude:
  - input/exclude[1-2].tpl
  - input/other_*.tpl
datasource:
  - data.yaml
  - data2.json
engine: gotemplates
allow-duplicate-keys: true

Development

Prerequisites

• Task
• pre-commit
• golangci-lint

Running locally

1. Fork and clone the repository

2. Install pre-commit hooks:

   pre-commit install

3. Run with:

   go run .

Running tests

task test             # Run all tests (including integration)
task test SHORT=true  # Run only unit tests