Add proof-of-concept for appoint wait times fetcher

Gemfile

@@ -36,6 +36,8 @@ gem "jbuilder", "~> 2.5"
 # Reduces boot times through caching; required in config/boot.rb
 gem "bootsnap", ">= 1.1.0", require: false
 
+gem "nokogiri"
+
 group :development, :test do
   # Call "byebug" anywhere in the code to stop execution and get a debugger console
   gem "byebug", platforms: [:mri, :mingw, :x64_mingw]

Gemfile.lock

@@ -227,6 +227,7 @@ DEPENDENCIES
   coffee-rails (~> 4.2)
   jbuilder (~> 2.5)
   listen (>= 3.0.5, < 3.2)
+  nokogiri
   pg (>= 0.18, < 2.0)
   pry-byebug
   puma (~> 3.11)

app/services/concerns/service.rb

@@ -0,0 +1,11 @@
+module Concerns
+  module Service
+    extend ActiveSupport::Concern
+
+    class_methods do
+      def call(*args, &block)
+        new(*args).call(&block)
+      end
+    end
+  end
+end

app/services/fetch_wait_times.rb

@@ -0,0 +1,29 @@
+require "openssl"
+require "open-uri"
+
+FetchWaitTimes = Struct.new(:consulate) do
+  include Concerns::Service
+
+  URI_HOST = "travel.state.gov"
+  URI_PATH = "/content/travel/resources/database/database.getVisaWaitTimes.html"
+
+  CATEGORIES = %i[ visitor student_exchange_visitor other_non_immigrant ]
+
+  delegate :code, to: :consulate, prefix: true
+
+  def uri
+    URI::HTTPS.build(host: URI_HOST, path: URI_PATH, query: URI.encode_www_form(cid: consulate_code))
+  end
+
+  def doc
+    @doc ||= Nokogiri::HTML(open(uri, ssl_verify_mode: OpenSSL::SSL::VERIFY_NONE))
+  end
+
+  def wait_times
+    %i[ visitor student_exchange_visitor other_non_immigrant ].zip(doc.text.split(/\s*,\s*/).take(3).map(&:to_i)).to_h
+  end
+
+  def call
+    CATEGORIES.zip(doc.text.split(/\s*,\s*/).take(CATEGORIES.size).map(&:to_i)).to_h
+  end
+end