A UI component library for Phlex using tailwindcss and daisyUI.
You can see a full list of the components at https://protos.inhouse.work/.
- Tailwindcss classes are merged using tailwind_merge.
- Uses tippy.js for dropdowns, combobox, and popovers
- All components avoid using
Phlex::DeferredRender
so you can reorder components exactly how you like them.
Other Phlex based UI libraries worth checking out:
Thinking of making your next static site using Phlex? Check out staticky. The protos docs were published using it.
Phlex is a fantastic framework for building frontend components in pure Ruby:
class Navbar
def view_template
header(class: "flex items-center justify-between") do
h3 { "My site" }
button { "Log out" }
end
end
end
But how can we sometimes render this Navbar
with a different background color?
It would be nice to have our components take a class like any other element:
render Navbar.new(class: "bg-primary")
Unfortunately class
is a special keyword in Ruby, so we need to do some
awkward handling to use it like this:
class Navbar
def initialize(**options)
# Keyword `class` is a special word in Ruby so we have to awkwardly unwrap
# like this instead of using keyword arguments
@classes = options[:class]
end
def view_template
header(class: "#{@classes} flex items-center justify-between") do
h3 { "My site" }
button { "Log out" }
end
end
end
Now we can pass in a style to our container, but what about overriding the style
of the h3
tag?
class Navbar
def initialize(**options)
# Keyword `class` is a special word in Ruby so we have to awkwardly unwrap
# like this instead of using keyword arguments
@container_classes = options[:class]
@title_classes = options[:title_class]
end
def view_template
header(class: "#{@classes} flex items-center justify-between") do
h3(class: @title_classes) { "My site" }
button { "Log out" }
end
end
end
Eventually everyone makes a kind of ad-hoc system for specifying styles. It gets more complicated when you have attributes like a data-controller. How do you give a good experience letting people using your components to add their own controllers while your component depends on one already?
This library is an attempt to make this kind of developer experience while making reusable components more convention over configuration.
A protos component follows 3 conventions that make them easy to work with as components in your app:
Every UI component library will have a tension between being too general to fit in your app or too narrow to be useful. Making components that look good out of the box can make them hard to customize.
We try and resolve this tension by making these components have a minimal style that can be easily overridden using some ergonomic conventions.
Components are styled with css
slots that get their values from a simple hash
we call a theme
.
You define a theme
for your component by defining a #theme
method that
returns a hash.
Users of your components can override, merge, or remove parts of your theme by passing in their own as an argument to the component. Another nice benefit is that your markup doesn't get overwhelmed horizontally with your css classes.
class List < Protos::Component
def view_template
ul(class: css[:list]) do
li(class: css[:item]) { "Item 1" }
li(class: css[:item]) { "Item 2" }
end
end
def theme
{
list: "space-y-4", # We can use `#tokens` from phlex (recommended)
item: "font-bold text-2xl" # Or just plain old strings
}
end
end
Using a theme and css slots allows us to easily override any part of a component when we render.
Here we are passing in our own theme. The default behavior is to add these styles on to the theme, rather than replacing them.
render List.new(
theme: {
list: "space-y-8",
item: "bg-red-500"
}
)
When the component is rendered the tailwind_merge
gem will also prune any
duplicate unneeded styles.
For example even though the themes list
key would be added together to become
space-y-4 space-y-8
, the tailwind_merge
gem will prune it down to just
space-y-8
as the two styles conflict.
<ul class="space-y-8">
<li class="font-bold text-2xl bg-red-500">Item 1</li>
<li class="font-bold text-2xl bg-red-500">Item 2</li>
</ul>
We can override the slot entirely by using a !
at the end of the key:
render List.new(
theme: {
item!: "bg-red-500"
}
)
The css slot css[:item]
would be overridden rather than merged:
<li class="bg-red-500">Item 1</li>
We can also negate a certain class or classes from the slot by putting a !
at the start of the key:
render List.new(
theme: {
"!item": "text-2xl"
}
)
The new css[:item]
slot would be:
<li class="font-bold">Item 1</li>
If you want to change the method we define our default theme under you can
override the theme_method
on the class:
class List < Protos::Component
theme_method :custom_theme
# ...
private
def custom_theme
{
list: tokens("space-y-4"),
item: tokens("font-bold", "text-2xl")
}
end
end
By convention, all components spread in an attrs
hash on their outermost
element of the component. There is no rule for this, but it makes them feel more
naturally like native html elements when you render them.
By doing this we enable 3 main conveniences:
- We can pass a
class
keyword when initializing the component which will be merged safely into thecss[:container]
slot - We can pass any html attributes we want to the element such as
id
,data
etc and it will just work - We can add default attributes that are safely merged with any provided to the component when its being initialized
class List < Protos::Component
def view_template
ul(**attrs) do
# ...
end
end
private
def default_attrs
{
data: { controller: "list" }
}
end
def theme
{
container: tokens("space-y-4"),
item: tokens("font-bold")
}
end
end
#attrs
returns a hash which will by default merge the class
keyword into the
css[:container]
slot which we define in our theme. The ul
elements class
would be space-y-4
as that is the css[:container]
on our theme.
Special html options will be safely merged. For examples, the component above defines a list controller. If we passed our own controller into data when we initialize, the component's data-controller attribute would be appended to:
render List.new(
data: { controller: "tooltip" }
)
That would output both controllers to the DOM element:
<ul data-controller="list tooltip">
This makes it very convenient to add functionality to basic components without overriding their core behavior or having to modify/override their class.
If we wanted to, just like for our theme we can change the method from
default_attrs
by defining the default_attrs_method
on the class:
class List < Protos::Component
default_attrs_method :custom_attrs
private
def custom_attrs
{
data: { controller: "list" }
}
end
end
Components extend
Dry::Initializer
which lets us easily add new positional arguments with param
or keyword
arguments with option
class List < Protos::Component
option :ordered
end
This makes our initializaiton declarative and easy to extend without having to
consider how to call super
in the initializer.
The following keywords are reserved in the base class:
class
theme
html_options
You are free to add whatever positional or keyword arguments you like as long as they don't directly conflict with those names.
Lets revisit the example of our Navbar
component:
require "protos"
class Navbar < Protos::Component
def view_template
header(**attrs) do
h1(class: css[:heading]) { "Hello world" }
h2(class: css[:subtitle]) { "With a subtitle" }
end
end
private
def default_attrs
{
data: { controller: "navbar" }
}
end
def theme
{
container: "flex justify-between items-center gap-sm",
heading: "text-2xl font-bold",
subtitle: "text-sm"
}
end
end
Now all the concerns about adding in our behavior, styles, etc are handled for us by convention:
render Navbar.new(
# This will add to the component's css[:container] slot
class: "my-sm",
# This will add the controller and not remove
# the existing one
data: { controller: "counter" },
theme: {
heading: "p-sm", # We can add tokens
"!container": "gap-sm" # We can negate (remove) certain tokens
subtitle!: "text-xl" # We can override the entire slot
}
)
Which produces the following html:
<header data-controller="navbar counter" class="flex justify-between items-center my-sm">
<h1 class="text-2xl font-bold p-sm">Hello world</h1>
<h2 class="text-xl">With a subtitle</h2>
</header>
Install the gem and add to the application's Gemfile by executing:
$ bundle add protos
If bundler is not being used to manage dependencies, install the gem by executing:
$ gem install protos
Setup Tailwindcss, daisyUI and add the protos path to your content.
npm install -D tailwindcss postcss autoprefixer daisyui
npx tailwindcss init
Then we need to add the protos path to the content
of our tailwindcss config
so tailwind will read the styles defined in the Protos gem.
Protos also uses semantic spacing such as p-sm
or m-md
instead of set
numbers so you can easily choose the spacing you want. So we will need to extend
spacing
in your theme.
// tailwind.config.js
// For importing tailwind styles from protos gem
const execSync = require('child_process').execSync;
const outputProtos = execSync('bundle show protos', { encoding: 'utf-8' });
const protos_path = outputProtos.trim() + '/**/*.rb';
module.exports = {
content: [
"./app/views/**/*.{rb,html,html.erb,erb}",
protos_path
],
theme: {
extend: {
spacing: {
xs: "var(--spacing-xs)",
sm: "var(--spacing-sm)",
md: "var(--spacing-md)",
lg: "var(--spacing-lg)",
xl: "var(--spacing-xl)",
},
},
}
// ....
}
Add protos-stimulus
to your packages:
npm install protos-stimulus
And somewhere in your entrypoints import as a side effect:
import "protos-stimulus"
Then you can use the components in your apps.
Protos::Card.new(class: "bg-base-100") do |card|
card.body(class: "gap-sm") do
card.title(class: "font-bold") { "Hello world" }
span { "This is some more content" }
card.actions do
button(class: "btn btn-primary") { "Action 1" }
end
end
end
You can override components simply by redefining sub-classing the class in your own app:
module Components
class Swap < Protos::Component
private
def on(...)
MyOnButton.new(...)
end
def theme
super.merge({
input: tokens("block", "bg-red-500")
})
end
end
end
But its much better to avoid the sub-classing and just render the component inside of your own:
module Components
class Swap < ApplicationComponent
def view_template
render Protos::Swap.new do |c|
# ....
end
end
end
end
You could use Proto::List
to create your own list and even use
Phlex::DeferredRender
to make the API more convenient.
Let's create a list component with headers and actions:
module Ui
class List < Protos::Component
include Protos::Typography
include Phlex::DeferredRender
option :title, default: -> {}
option :ordered, default: -> { false }
option :items, default: -> { [] }, reader: false
option :actions, default: -> { [] }, reader: false
def template
article(**attrs) do
header class: css[:header] do
h3(size: :md) { title }
nav(class: css[:actions]) do
@actions.each do |action|
render action
end
end
end
render Protos::List.new(ordered:, class: css[:list]) do
@items.each { |item| render item }
li(&@empty) if @items.empty?
end
end
end
def with_item(*, **, &block)
theme = { container: css[:item] }
@items << Protos::List::Item.new(*, theme:, **, &block)
end
def with_action(&block)
@actions << block
end
def with_empty(&block)
@empty = block
end
private
def theme
{
container: tokens("space-y-xs"),
header: tokens("flex", "justify-between", "items-end", "gap-sm"),
list: tokens("divide-y", "border", "w-full"),
actions: tokens("space-x-xs"),
item: tokens("p-sm")
}
end
end
end
Now the component is specific to our application, and the styles are still overridable at all levels:
render Ui::List.new(title: "Project Names", ordered: true) do |list|
list.with_action { link_to("Add item", "#") }
list.with_item(class: "active") { "Project 1" }
list.with_item { "Project 2" }
list.with_item { "Project 3" }
end
Or here is another example of a table:
module Ui
class Table < ApplicationComponent
include Protos::Typography
include Phlex::DeferredRender
include Actionable
class Column
attr_reader :title
def initialize(title, &block)
@title = title
@block = block
end
def call(item)
@block.call(item)
end
end
option :title, default: -> {}
option :collection, default: -> { [] }, reader: false
option :columns, default: -> { [] }, reader: false
def template
article(**attrs) do
header class: css[:header] do
h3(size: :md) { title } if title.present?
nav(class: css[:actions]) do
@actions.each do |action|
render action
end
end
end
render Protos::Table.new(class: css[:table]) do |table|
render(table.caption(class: css[:caption]), &@caption) if @caption
render table.header do
render table.row do
@columns.each do |column|
render table.head do
plain(column.title)
end
end
end
end
render table.body do
@collection.each do |item|
render table.row do
@columns.each do |column|
render table.cell do
column.call(item)
end
end
end
end
if @collection.empty?
render table.row do
render table.cell(colspan: @columns.length) do
@empty&.call
end
end
end
end
end
end
end
def with_column(...)
@columns << Column.new(...)
end
def with_empty(&block)
@empty = block
end
def with_caption(&block)
@caption = block
end
def with_action(&block)
@actions << block
end
private
def theme
{
container: tokens("space-y-sm"),
header: tokens("flex", "justify-between", "items-end", "gap-sm"),
table: tokens("border"),
caption: tokens("text-muted")
}
end
end
end
Which lets you have a very nice table builder:
collection = [
{
name: "John Doe",
status: "Active",
location: "New York"
}
]
render Ui::Table.new(title: "A table", collection:) do |table|
table.with_caption { "Users" }
table.with_action do
a(href: "#") { "Add new" }
end
table.with_column("Name") { |row| row[:name] }
table.with_column("Location") { |row| row[:location] }
table.with_column("Status") do |row|
span(class: "badge badge-info") { row[:status] }
end
table.with_column("Actions") do
a(href: "#") { "View" }
end
end
This library avoids re-making Protos components for extremely simple daisyui components such as:
- Badge
- Buttons
- Checkbox
- File input
- Indicator
- Join
- Kbd
- Link
- Loading
- Mask
- Progress
- Radial progress
- Radio
- Range
- Select
- Skeleton
- Stack
- Text input
- Textarea
- Toggle
- Tooltip
After checking out the repo, run bin/setup
to install dependencies. Then, run
rake spec
to run the tests. You can also run bin/console
for an interactive
prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install
. To
release a new version, update the version number in version.rb
, and then run
bundle exec rake release
, which will create a git tag for the version, push
git commits and the created tag, and push the .gem
file to
rubygems.org.
Bug reports and pull requests are welcome on GitHub at https://github.com/inhouse-work/protos.
You can run the benchmarks using the raketasks, e.g:
bin/rake benchmark:ips:table
bin/rake benchmark:memory:table
bin/rake benchmark:ips:theme
bin/rake benchmark:ips:attributes
There are also tasks for profiling and exploring memory consumption.
You can find the latest benchmarks in benchmarks/
. These were run on a new
Macbook M3 Pro chip.
Currently this library is 30x slower than plain Phlex components. This is due to the overhead of themes, attributes and other quality of life improvements.
This may seem like a lot but Phlex is so fast that rendering a large table can still be done 4000 times per second with this lib.
The gem is available as open source under the terms of the MIT License.