playgroundbook
A series of tools for Swift Playground and Playground books based on Apple's documentation.
It's a work in progress (see issues) but you can use it now.
Installation
> [sudo] gem install playgroundbook
Usage
To lint an existing playground book:
> playgroundbook lint MyPlaygroundbook.playgroundbook
To generate a playground book:
> playgroundbook render book.yaml
The yml file should be in the following format:
name: Testing book
identifier: com.ashfurrow.example
resources: assets # Optional
cover: cover.jpeg # Optional
deployment_target: ios10.0 # Optional
imports: # Optional, defaults to UIKit
- UIKit
- CoreGraphics
chapters:
- name: Chapter 1
edge_to_edge_live_view: false # defaults to true
live_view_mode: "VisibleByDefault" # defaults to "HiddenByDefault"
- name: Chapter 2
- etc...
glossary:
term: definition
Each chapter needs to have a corresponding playground; so Chapter 1
requires there be a Chapter 1.playground
playground. The playgrounds can reference (not copy) resources from an optionally specified directory. import
frameworks are specified in the yaml file and are added to every page of the book. You can specify a cover image file name that's stored in the resources
directory (it should be 400x300 pixels). Finally, you can supply a glossary, a dictionary of term/definition pairs. This lets you link to terms in markdown. For example:
... [term](glossary://term) ...
Only the link to the term must be URL encoded. For example, the term "reuse identifier" would be defined in the yaml as reuse identifier
but linked to as glossary://reuse%20identifier
.
Each chapter needs to be in the following format:
// This is the preamble that is shared among all the pages within this chapter.
public var str = "Hi!"
public func sharedFunc() {
print("This should be accessible to all pages.")
}
//// Page 1
str = "Yo, it's page 1."
sharedFunc()
//// Page 2
sharedFunc()
str = "Page 2 awww yeah."
Pages are divided by lines beginning with a quadruple slash, followed by that pages name.
Limitations of Book Rendering
Preamble (anything about the first ////
page) is put in its own file. That means declarations there need to be public
to be visible within individual pages (even though when you're writing, everything is in one file). Additionally, the preamble is at the top-level and can't contain expressions. This would cause a compiler error in the Swift Playrounds iPad app:
public let layout = UICollectionViewFlowLayout()
layout.itemSize = CGSize(width: 20, height: 20)
Instead, you have to wrap it in a closure, like this:
public var layout: UICollectionViewFlowLayout = {
let layout = UICollectionViewFlowLayout()
layout.itemSize = CGSize(width: 20, height: 20)
return layout
}()
It's awkward; if you have suggestions, open an issue
Sharing resources is only available book-wide and not specific to chapters. Sharing code outside the preamble isn't supported yet.
Playground books support a rich set of awesome features to make learning how to code really easy, and this tool uses almost none of them. It sacrifices this experience for the sake of being able to easily write the books on your Mac.
Creating a Playground from markdown
Maybe you want to do something for a website, or a git repo first, and then generate your Playground? Well in those cases your source of truth is the markdown document. For that case, we have playgroundbook wrapper
.
For example, you might have a folder that looks like:
> tree Beginners/Lesson\ One
Beginners/Lesson\ One
βββ README.md
βββ README_ZH.md
βββ img
βββ emptyplayground.png
βββ multipleresults.png
βββ newplayground.png
βββ results.png
βββ tentimes.png
βββ welcome.png
You can run:
playgroundbook wrapper "Beginners/Lesson\ One/README.md" "Lesson One"
And it will switch out swift codeblocks into the playground. You have to use triple backticks with swift ```swift
. No space between them. You should avoid using backtick blocks for anything other than Swift code, if you need to show examples, use Markdown's indentation rules with four spaces.
> tree Beginners/Lesson\ One
Beginners/Lesson\ One
βββ Lesson\ One.playground
β βββ Contents.swift
β βββ Resources
β β βββ img
β β βββ emptyplayground.png
β β βββ newplayground.png
β β βββ results.png
β β βββ welcome.png
β βββ contents.xcplayground
β βββ timeline.xctimeline
βββ README.md
...
You might notice that a subset of images, have moved well, they're the only one being used in the README.md
. Slick huh?
Contributing
Hey! Like this tool? Awesome! We could actually really use your help!
Open source isn't just writing code. We could use your help with any of the following:
- Finding (and reporting!) bugs.
- New feature suggestions.
- Answering questions on issues.
- Reviewing pull requests.
- Helping to manage issue priorities.
- Fixing bugs/new features.
If any of that sounds cool to you, send a pull request! After a few
contributions, we'll add you as an admin to the repo so you can merge pull
requests and help steer the ship
Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by [its terms](https://github.com/playgroundbooks/playgroundbook/blob/master/Code of Conduct.md).
License
MIT, except for the starter.playgroundbook
in the unit tests, which is licensed by Apple.