Jbuilder gives you a simple DSL for declaring JSON structures that beats massaging giant hash structures. This is particularly helpful when the generation process is fraught with conditionals and loops. Here's a simple example:
Jbuilder.encode do |json|
json.content format_content(@message.content)
json.(@message, :created_at, :updated_at)
json.author do |json|
json.name @message.creator.name.familiar
json.email_address @message.creator.email_address_with_name
json.url url_for(@message.creator, format: :json)
end
if current_user.admin?
json.visitors calculate_visitors(@message)
end
json.comments @message.comments, :content, :created_at
json.attachments @message.attachments do |json, attachment|
json.filename attachment.filename
json.url url_for(attachment)
end
endThis will build the following structure:
{
"content": "<p>This is <i>serious</i> monkey business",
"created_at": "2011-10-29T20:45:28-05:00",
"updated_at": "2011-10-29T20:45:28-05:00",
"author": {
"name": "David H.",
"email_address": "'David Heinemeier Hansson' <[email protected]>",
"url": "http://example.com/users/1-david.json"
},
"visitors": 15,
"comments": [
{ "content": "Hello everyone!", "created_at": "2011-10-29T20:45:28-05:00" },
{ "content": "To you my good sir!", "created_at": "2011-10-29T20:47:28-05:00" }
],
"attachments": [
{ "filename": "forecast.xls", "url": "http://example.com/downloads/forecast.xls" },
{ "filename": "presentation.pdf", "url": "http://example.com/downloads/presentation.pdf" }
]
}Top level arrays can be handled directly. Useful for index and other collection actions.
# @people = People.all
json.array!(@people) do |json, person|
json.name person.name
json.age calculate_age(person.birthday)
end
# => [ { "name": David", "age": 32 }, { "name": Jamie", "age": 31 } ]You can either use Jbuilder stand-alone or directly as an ActionView template language. When required in Rails, you can create views ala show.json.jbuilder (the json is already yielded):
# Any helpers available to views are available to the builder
json.content format_content(@message.content)
json.(@message, :created_at, :updated_at)
json.author do |json|
json.name @message.creator.name.familiar
json.email_address @message.creator.email_address_with_name
json.url url_for(@message.creator, format: :json)
end
if current_user.admin?
json.visitors calculate_visitors(@message)
end
# You can use partials as well. The following line will render the file
# RAILS_ROOT/app/views/api/comments/_comments, and set a local variable
# 'comments' with all this message's comments, which you can use inside
# the partial.
json.partial! "api/comments/comments", comments: @message.commentsLibraries similar to this in some form or another include:
- RABL: https://github.com/nesquena/rabl
- JsonBuilder: https://github.com/nov/jsonbuilder
- JSON Builder: https://github.com/dewski/json_builder
- Jsonify: https://github.com/bsiggelkow/jsonify
- RepresentationView: https://github.com/mdub/representative_view
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent