Hanami::API

Minimal, extremely fast, lightweight Ruby framework for HTTP APIs.

• Installation
• Performance
  • Runtime
  • Memory
  • Requests per second
• Usage
  • Routes
  • HTTP methods
  • Endpoints
    • Rack endpoint
    • Block endpoint
      • String (body)
      • Integer (status code)
      • Integer, String (status code, body)
      • Integer, Hash, String (status code, headers, body)
  • Block context
    • env
    • status
    • headers
    • body
    • params
    • halt
    • redirect
    • back
    • json
  • Scope
  • Rack Middleware
  • Body Parsers
• Development
• Contributing

Installation

Add this line to your application's Gemfile:

gem "hanami-api"

And then execute:

$ bundle install

Or install it yourself as:

$ gem install hanami-api

Performance

Benchmark against an app with 10,000 routes, hitting the 10,000th to measure the worst case scenario. Based on jeremyevans/r10k, Hanami::API scores first for speed, and second for memory footprint.

Runtime

Runtime to complete 20,000 requests (lower is better).

Memory

Memory footprint for 10,000 routes app (lower is better).

Requests per second

For this benchmark there are two apps for each framework: one with the root route, and one with 10,000 routes. Requests per second hitting the 1st (and only route) and the 10,000th route to measure the best and worst case scenario (higher is better).

Usage

Create config.ru at the root of your project:

# frozen_string_literal: true

require "bundler/setup"
require "hanami/api"

class App < Hanami::API
  get "/" do
    "Hello, world"
  end
end

run App.new

Start the Rack server with bundle exec rackup

Routes

A route is a combination of three elements:

• HTTP method (e.g. get)
• Path (e.g. "/")
• Endpoint (e.g. MyEndpoint.new)

get "/", to: MyEndpoint.new

HTTP methods

Hanami::API supports the following HTTP methods:

• get
• head
• post
• patch
• put
• options
• trace
• link
• unlink

Endpoints

Hanami::API supports two kind of endpoints: block and Rack.

Rack endpoint

The framework is compatible with Rack. Any Rack endpoint, can be passed to the route:

get "/", to: MyRackEndpoint.new

Block endpoint

A block passed to the route definition is named a block endpoint. The returning value will compose the Rack response. It can be:

String (body)

get "/" do
  "Hello, world"
end

It will return [200, {}, ["Hello, world"]]

Integer (status code)

get "/" do
  418
end

It will return [418, {}, ["I'm a teapot"]]

Integer, String (status code, body)

get "/" do
  [401, "You shall not pass"]
end

It will return [401, {}, ["You shall not pass"]]

Integer, Hash, String (status code, headers, body)

get "/" do
  [401, {"X-Custom-Header" => "foo"}, "You shall not pass"]
end

It will return [401, {"X-Custom-Header" => "foo"}, ["You shall not pass"]]

Block context

When using the block syntax there is a rich API to use.

env

The #env method exposes the Rack environment for the current request

status

Get HTTP status

get "/" do
  puts status
    # => 200
end

Set HTTP status

get "/" do
  status(201)
end

headers

Get HTTP response headers

get "/" do
  puts headers
    # => {}
end

Set HTTP status

get "/" do
  headers["X-My-Header"] = "OK"
end

body

Get HTTP response body

get "/" do
  puts body
    # => nil
end

Set HTTP response body

get "/" do
  body "Hello, world"
end

params

Access params for current request

get "/" do
  id = params[:id]
  # ...
end

halt

Halts the flow of the block and immediately returns with the current HTTP status

get "/authenticate" do
  halt(401)

  # this code will never be reached
end

It sets a Rack response: [401, {}, ["Unauthorized"]]

get "/authenticate" do
  halt(401, "You shall not pass")

  # this code will never be reached
end

It sets a Rack response: [401, {}, ["You shall not pass"]]

redirect

Redirects request and immediately halts it

get "/legacy" do
  redirect "/dashboard"

  # this code will never be reached
end

It sets a Rack response: [301, {"Location" => "/new"}, ["Moved Permanently"]]

get "/legacy" do
  redirect "/dashboard", 302

  # this code will never be reached
end

It sets a Rack response: [302, {"Location" => "/new"}, ["Moved"]]

back

Utility for redirect back using HTTP request header HTTP_REFERER

get "/authenticate" do
  if authenticate(env)
    redirect back
  else
    # ...
  end
end

json

Sets a JSON response for the given object

get "/user/:id" do
  user = UserRepository.new.find(params[:id])
  json(user)
end

get "/user/:id" do
  user = UserRepository.new.find(params[:id])
  json(user, "application/vnd.api+json")
end

Scope

Prefixing routes is possible with routing scopes:

scope "api" do
  scope "v1" do
    get "/users", to: Actions::V1::Users::Index.new
  end
end

It will generate a route with "/api/v1/users" as path.

Rack Middleware

To mount a Rack middleware it's possible with .use

# frozen_string_literal: true

require "bundler/setup"
require "hanami/api"

class App < Hanami::API
  use ElapsedTime

  scope "api" do
    use ApiAuthentication

    scope "v1" do
      use ApiV1Deprecation
    end

    scope "v2" do
      # ...
    end
  end
end

Middleware are inherited from top level scope.

In the example above, ElapsedTime is used for each incoming request because it's part of the top level scope. ApiAuthentication it's used for all the API versions, because it's defined in the "api" scope. ApiV1Deprecation is used only by the routes in "v1" scope, but not by "v2".

Body Parsers

Rack ignores request bodies unless they come from a form submission. If you have an endpoint that accepts JSON, the request payload isn’t available in params.

In order to parse JSON payload and make it avaliable in params, you should add the following lines to config.ru:

# frozen_string_literal: true
require "hanami/middleware/body_parser"

use Hanami::Middleware::BodyParser, :json

Development

After checking out the repo, run bin/setup to install dependencies. 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 tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/hanami/api.