RubyのWebアプリケーションフレームワーク「Ruby on Rails」でWeb APIを作成する

gem "grape"

bundle install

rails generate model Invoice billno:string slipno:string customerid:string customername:string products:string number:integer unitprice:integer date:datetime

Invoice.create(billno: 'WS-DF502', slipno:'GB465', customerid:'1', customername:'長崎カントリーフーズ', products: 'コーヒー 250 ml', number: '100', unitprice: '100', date:'2022-01-05T00:00:00')
Invoice.create(billno: 'WS-DF502', slipno:'GB465', customerid:'1', customername:'長崎カントリーフーズ', products: '紅茶 350 ml', number: '300', unitprice: '120', date:'2022-01-05T00:00:00')
Invoice.create(billno: 'WS-DF502', slipno:'DK055', customerid:'1', customername:'長崎カントリーフーズ', products: '炭酸飲料 (オレンジ） 350 ml', number: '200', unitprice: '120', date:'2022-01-09T00:00:00')

rails db:migrate

rails db:seed

rails dbconsole

select * from invoices;

Rails.application.routes.draw do
  mount API => '/'
end

ActiveSupport::Inflector.inflections(:en) do |inflect|
  inflect.acronym 'API'
end

class API < Grape::API
  prefix 'api'
  mount Resources::V1::Root
end

module Resources
  module V1
    class Root < Grape::API
      version 'v1'
      format :json
      content_type :json, 'application/json'
  
      mount Resources::V1::Invoices
    end
  end
end

module Resources
    module V1
      class Invoices < Grape::API
        resource :invoices do
          desc 'Return an invoice data.'
          get do
            present Invoice.all
          end

          desc 'Return all invoice data.'
          params do
            requires :id, type: Integer, desc: 'invoice id.'
          end
          get ':id' do
            present Invoice.find(params[:id])
          end

          desc 'Create an invoice data.'
          params do
            requires :billno, type: String, desc: 'bill no of invoice'
            requires :slipno, type: String, desc: 'slip no of invoice'
            requires :customerid, type: String, desc: 'customer id'
            requires :customername, type: String, desc: 'customer name'
            requires :products, type: String, desc: 'products name'
            requires :number, type: Integer, desc: 'number of products'
            requires :unitprice, type: Integer, desc: 'unitprice of products'
            requires :date, type: DateTime, desc: 'date of invoice'
          end
          post do
            Invoice.create({
                billno: params[:billno],
                slipno: params[:slipno],
                customerid: params[:customerid],
                customername: params[:customername],
                products: params[:products],
                number: params[:number],
                unitprice: params[:unitprice],
                date: params[:date]
            })
          end
    
          desc 'Update an invoice data.'
          params do
            requires :id, type: String, desc: 'invoice id.'
          end
          put ':id' do
            Invoice.find(params[:id]).update({
                billno: params[:billno],
                slipno: params[:slipno],
                customerid: params[:customerid],
                customername: params[:customername],
                products: params[:products],
                number: params[:number],
                unitprice: params[:unitprice],
                date: params[:date]
            })
          end

          desc 'Delete an invoice data.'
          params do
            requires :id, type: String, desc: 'invoice id.'
          end
          delete ':id' do
            Invoice.find(params[:id]).destroy
          end

        end
      end
    end
  end

gem 'rack-cors', :require => 'rack/cors'

bundle install

・・・（中略）
module Myapp
  class Application < Rails::Application
    config.load_defaults 7.0
    config.middleware.use Rack::Cors do
      allow do
        origins "*"
        resource "*", headers: :any, methods: [:get, :post, :put, :delete, :options]
      end
    end
  end
end

require_relative "config/environment"
require 'rack/cors'

use Rack::Cors do
  allow do
    origins '*'
    resource '*', headers: :any, methods: :any
  end
end

run Rails.application
Rails.application.load_server

rails server

{
    "billno": "WS-DF502",
    "slipno": "YJ215",
    "customerid": "1",
    "customername": "長崎カントリーフーズ",
    "products": "ピリピリ ビール",
    "number": 80,
    "unitprice": 100,
    "date": "2022-01-12T00:00:00"
}

{
    "billno": "WS-DF502-Upd",
    "slipno": "YJ215-Upd",
    "customerid": "999",
    "customername": "長崎カントリーフーズ-Upd",
    "products": "ピリピリ ビール-Upd",
    "number": 999,
    "unitprice": 999,
    "date": "2022-12-31T00:00:00"
}