JsonSchemaView

JsonSchemaView is a view framework that brings Schema-driven Development to Rails view and another view frameworks (e.g react_on_rails).

JsonSchemaView is a Ruby object:

class TodoItemComponent < JsonSchemaView::BaseComponent
  renderer_class :react_on_rails

  props_class do
    property :title, type: String
    property :done, type: [TrueClass, FalseClass]

    attr_reader :title, :done

    def initialize(title:, done:)
      @title = title
      @done = done
    end
  end
end

The component can be passed to Rails' render and then its schema validates its props:

render TodoItemComponent.new(props: { title: 'Buy milk', done: false }) # => Valid against schema. Renders a view by using renderer (react_on_rails)

render TodoListComponent.new(props: { title: 'Buy milk', done: "Invalid value" }) # => Invalid. Raises an error.

The component's schema can be exported as JSON Schema:

// TodoItemComponent.to_json_schema
{
  "type": "object",
  "properties": {
    "title": {
      "type": "string"
    },
    "done": {
      "type": "boolean"
    }
  },
  "required": ["title", "done"],
  "additional_properties": false
}

Its JSON Schema can be used to generate type definitions for other languages. It helps consistent typing between different languages:

import type { TodoItemComponentProps } from './generated-types-from-json-schema/TodoItemComponent';

export const TodoItemComponent = ({ title, done }: TodoItemComponentProps) => {
  return (
    <div>
      <input type="checkbox" checked={done} />
      <label>{title}</label>
    </div>
  );
};

1. Install the gem and add to the application's Gemfile by executing:

$ bundle add json_schema_view

2. Run the generator:

$ bin/rails generate json_schema_view:install
    create  config/initializers/json_schema_view.rb
    create  app/components/base_component.rb
    create  app/components/base_props.rb
    create  app/components/json_schema_definable.rb
    create  app/components/component_schema_set.rb
    create  app/components/example_todo_list_component.rb
    create  app/components/example_todo_list_component/todo_item_resource.rb

This task sets up app/components as the place of component definitions and an example component :-)

JsonSchemaView provides a rake task to export JSON Schema of components:

$ rake json_schema_view:export[primary]
Exports resource classes in ComponentSchemaSet...
ExampleTodoListComponent -> /path/to/rails/application/json_schema/ExampleTodoListComponent.json

The behavior of the export task (output directory, classes to export, ...etc) can be configured on ComponentSchemaSet.

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/increments/json_schema_view. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

Everyone interacting in the JsonSchemaView project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.