Restart API endpoint

Redis configuration added to backend method
Manager instance now restarts
Logger included in metrics
Spec test added
API doc updated

docs/API.md

@@ -890,3 +890,23 @@ $ curl -X DELETE https://vmpooler.example.com/api/v1/ondemandvm/e3ff6271-d201-4f
   "ok": true
 }
 ```
+
+##### GET /restart
+
+Restart vmpooler
+
+An authentication token is required from an authorized user.
+
+Responses:
+* 200 - The restart was successful and status is ok
+* 404 - No auth token provided, or provided auth token is not valid
+
+```
+$ curl -X GET -H X-AUTH-TOKEN:a9znth9dn01t416hrguu56ze37t790bl --url https://vmpooler.example.com/restart
+```
+```json
+{
+  "ok": true
+  "message": "Restarting ..."
+}
+```

lib/vmpooler/api.rb

@@ -3,7 +3,7 @@
 module Vmpooler
   class API < Sinatra::Base
     # Load API components
-    %w[helpers dashboard reroute v1 request_logger healthcheck].each do |lib|
+    %w[helpers dashboard reroute v1 request_logger healthcheck restart].each do |lib|
       require "vmpooler/api/#{lib}"
     end
     # Load dashboard components
@@ -44,6 +44,7 @@ module Vmpooler
         # However, prometheus setup includes the web server which is required for this check
         # At this time prometheus is a requirement of using the health check on manager
         use Vmpooler::API::Healthcheck
+        use Vmpooler::API::Restart, logger: logger
       end
 
       if torun.include? :api
@@ -54,6 +55,7 @@ module Vmpooler
         use Vmpooler::API::Dashboard
         use Vmpooler::API::Reroute
         use Vmpooler::API::V1
+        use Vmpooler::API::Restart, logger: logger
       end
 
       # Get thee started O WebServer

lib/vmpooler/api/restart.rb

@@ -0,0 +1,49 @@
+require 'json'
+
+module Vmpooler
+  class API
+    class Restart < Sinatra::Base
+      helpers do
+        include Vmpooler::API::Helpers
+      end
+
+      # rubocop:disable Lint/MissingSuper
+      def initialize(app, options = {})
+        @app = app
+        @logger = options[:logger]
+      end
+
+      def backend
+        config = Vmpooler.config
+        redis_host = config[:redis]['server']
+        redis_port = config[:redis]['port']
+        redis_password = config[:redis]['password']
+        Vmpooler.new_redis(redis_host, redis_port, redis_password)
+      end
+
+      def need_token!
+        validate_token(backend)
+      end
+
+      def exit_process
+        Thread.new do
+          at_exit do
+            @logger.log('ignored', 'Restarting VMPooler')
+          end
+          sleep(5)
+          exit!
+        end
+      end
+
+      get '/restart/?' do
+        # token authentication
+        need_token!
+
+        # restart operation
+        exit_process
+        status 200
+        JSON.pretty_generate({ 'ok' => true, 'message' => 'Restarting ...' })
+      end
+    end
+  end
+end

spec/integration/api/restart_spec.rb

@@ -0,0 +1,30 @@
+require 'spec_helper'
+require 'rack/test'
+
+describe Vmpooler::API::Restart do
+  include Rack::Test::Methods
+
+  def app()
+    Vmpooler::API
+  end
+
+  # Added to ensure no leakage in rack state from previous tests.
+  # Removes all routes, filters, middleware and extension hooks from the current class
+  # https://rubydoc.info/gems/sinatra/Sinatra/Base#reset!-class_method 
+  before(:each) do
+    app.reset!
+  end
+
+
+
+  describe '/restart' do  
+
+    it 'returns OK' do
+      get "/restart"
+      
+      expect(last_response.status).to eq(200)
+      result = JSON.parse(last_response.body)
+      expect(result).to eq({'ok' => true})
+    end 
+  end  
+end