add rfid tags controller

app/controllers/rfid_tags_controller.rb

@@ -0,0 +1,30 @@
+class RfidTagsController < ApplicationController
+  skip_forgery_protection
+
+  def create
+    identifier = params.expect(:identifier)
+    rfid_tag = RfidTag.find_or_initialize_by(identifier:)
+    if rfid_tag.new_record?
+      register rfid_tag
+      return
+    end
+
+    create_mood(rfid_tag)
+  end
+
+  private
+
+  def register(rfid_tag)
+    rfid_tag.save!
+    head :created, code: :registered
+  end
+
+  def create_mood(rfid_tag)
+    if rfid_tag.mode
+      Mood.create!(recorded_at: DateTime.now, mode: rfid_tag.mode)
+      head :created, code: :recorded
+    else
+      head :unprocessable_entity
+    end
+  end
+end

app/helpers/rfid_tags_helper.rb

@@ -0,0 +1,2 @@
+module RfidTagsHelper
+end

app/views/rfid_tags/post.html.erb

@@ -0,0 +1,2 @@
+<h1>RfidTags#post</h1>
+<p>Find me in app/views/rfid_tags/post.html.erb</p>

config/routes.rb

@@ -1,4 +1,5 @@
 Rails.application.routes.draw do
+  post '/rfid_tags' => 'rfid_tags#create'
   # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
 
   # Reveal health status on /up that returns 200 if the app boots with no exceptions, otherwise 500.

test/controllers/rfid_tags_controller_test.rb

@@ -0,0 +1,8 @@
+require "test_helper"
+
+class RfidTagsControllerTest < ActionDispatch::IntegrationTest
+  test "should get post" do
+    get rfid_tags_post_url
+    assert_response :success
+  end
+end