Genesis

Genesis is a templating and scaffolding tool.

A Genesis template is a manifest of options and files written in yaml or json. Option values can be provided in various ways otherwise you will be interactively asked for inputs. Template files are written in Stencil. The list of files can make use of dynamic paths and be generated multiple times depending on the format of the input.

• ✅ Template manifests in easy to read and write yaml or json
• ✅ Template files written in Stencil templating language
• ✅ Provide options via ENV, command line, file or interactively
• ✅ Powerful command line interactivity with choices, lists and branching
• ✅ Write dynamic file paths

The very simple example:

options:
  - name: project
    description: The name of the project
    question: What is the name of your project?
    required: true
    type: string
files:
  - template: project.stencil
    path: "{{ project }}.project"

And then run like this:

$ genesis generate template.yml
What is the name of your project? MyProject
Generated files:
  MyProject.project

Or you can provide the required options via arguments

$ genesis generate template.yml --options name:MyProject
Generated files:
  MyProject.project

Much more powerful templates are possible. See more complete documentation here

Installing

Make sure Xcode 13 is installed first.

Mint

$ mint install yonaskolb/genesis

Make

$ git clone https://github.com/yonaskolb/Genesis.git
$ cd Genesis
$ make

Swift Package Manager

Use CLI

$ git clone https://github.com/yonaskolb/Genesis.git
$ cd Genesis
$ swift run mint

Use as dependency

Add the following to your Package.swift file’s dependencies:

.package(url: "https://github.com/yonaskolb/Genesis.git", from: "0.1.0"),

And then import GenesisKit. See GenesisKit for more information.

Usage

Run genesis help for usage instructions

Usage: genesis generate <templatePath> [options]

Options:
  -d, --destination <value>    Path to the directory where output will be generated. Defaults to the current directory
  -h, --help                   Show help information for this command
  -n, --non-interactive        Do not prompt for required options
  -o, --options <value>        Provide option overrides, in the format --options "option1: value 2, option2: value 2.
  -p, --option-path <value>    Path to a yaml or json file containing options

Providing options

Options will be passed to the template in the following order, merging along the way, with duplicate options overriding the previous ones.

1. Environment Variables

Set any environment variables before you call generate, or use already existing ones from your development environment

name="My Name" genesis generate template.yml

2. Options File

Pass a path to a json or yaml file with --option-file
This can include more structures and complex data. For example:

name: MyProject
targets:
  - name: MyTarget
    type: application
  - name: MyFramework
    type: framework  

3. Options Argument

Pass specific options with --options like this

-- options "option1: value 2, option2: value 2"

4. Interactive input

Genesis will ask you for any missing options if they are required. You can turn off interactive input with --non-interactive.

5. Default value

Each option can have a default value which be used as a fallback.

Missing value

If an option is required and still hasn’t received a value from anywhere, generation will fail.

Template

A genesis template is a yaml or json file that includes a list of options and files

Options

Options are structured input for the Stencil templates. They serve as documentation and allow for Genesis to interactively ask for input.

• name: This is the name that is referenced in the template as well as the command line
• value: This is the default value that will be used if none are provided. This can have Stencil tags in it
• question: The question that is asked when asking for input. This can have Stencil tags in it
• description: An extended description of the option and what it does
• required: Whether this option is required or not for the template to generate. If it is not provided via the command line, option file, or input, generation will fail
• type: This is the type of option. It defaults to string but can be any one of the following:
  • string a simple string
  • boolean a boolean
  • choice a string from a list of choices. Requires choices to be defined
  • array an array of other options. If child options are defined, if will be an array of options, otherwise it will split a string by command, removing any whitespace between
• options: An array of child options. Used if the array type contains objects

Files

• path: This is the path the file will be generated at. It can include Stencil tags to make it dynamic.
• contents: A file template string
• template: A path to a file template
• copy: A path to copy. This can be a file or a directory
• context: An optional context property path that will be passed to the template. If this resolves to an array, a file for each element will be created, using tags in path to differentiate them.
• include: Whether the file should be written. This is a Stencil if tag without the braces. For example instead of {% if type == 'framework' %} you would write type == 'framework'

Stencil Templates

Each Stencil template has all the filters available in StencilSwiftKit, and has access to all the options. See Stencil for more info about tags.

Small example:

{% if name %}
name: {{ name }}
{% endif %}

GenesisKit

The library GenesisKit can be used to easily provide generation in your own tools.

import GenesisKit

// create a context
let context: [String: Any] = ["name": "hello"]

// create a template, either from a file or programmatically
let template = try GenesisTemplate(path: "template.yml")

// Create the generator
let generator = try TemplateGenerator(template: template)

// generate the files
let generationResult = try generator.generate(context: context, interactive: false)

// write the files to disk
try generationResult.writeFiles(path: "destination")

Contributions

Pull requests and issues are welcome

License

Genesis is licensed under the MIT license. See LICENSE for more info.