Fixed #269 Add health-check endpoint (GRN-3) (#290)

* <Added health_check endpoint>

* <changed gemfile_lock>

* <fixed code style>

* <removed excess health_check routes>

Gemfile

@@ -66,6 +66,9 @@ gem 'http_accept_language'
 # Markdown parsing.
 gem 'redcarpet'
 
+# For health check endpoint
+gem "health_check"
+
 group :production do
   # Use a postgres database in production.
   gem 'pg', '~> 0.18'

Gemfile.lock

@@ -97,6 +97,8 @@ GEM
       activesupport (>= 4.2.0)
     hashdiff (0.3.7)
     hashie (3.5.7)
+    health_check (3.0.0)
+      railties (>= 5.0)
     http-cookie (1.0.3)
       domain_name (~> 0.5)
     http_accept_language (2.1.1)
@@ -327,6 +329,7 @@ DEPENDENCIES
   dotenv-rails
   factory_bot_rails
   faker
+  health_check
   http_accept_language
   jbuilder (~> 2.5)
   jquery-rails

config/initializers/health_check.rb

@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+# Health check to monitor the status of the rails server
+HealthCheck.setup do |config|
+  # uri prefix (no leading slash)
+  config.uri = 'health_check'
+
+  # Text output upon success
+  config.success = 'success'
+
+  # Timeout in seconds used when checking smtp server
+  config.smtp_timeout = 30.0
+
+  # http status code used when plain text error message is output
+  # Set to 200 if you want your want to distinguish between partial (text does not include success) and
+  # total failure of rails application (http status of 500 etc)
+
+  config.http_status_for_error_text = 500
+
+  # http status code used when an error object is output (json or xml)
+  # Set to 200 if you want your want to distinguish between partial (healthy property == false) and
+  # total failure of rails application (http status of 500 etc)
+
+  config.http_status_for_error_object = 500
+
+  # bucket names to test connectivity - required only if s3 check used, access permissions can be mixed
+  config.buckets = { 'bucket_name' => [:R, :W, :D] }
+
+  # You can customize which checks happen on a standard health check, eg to set an explicit list use:
+  config.standard_checks = %w(database migrations custom)
+
+  # Or to exclude one check:
+  config.standard_checks -= %w(emailconf)
+
+  # You can set what tests are run with the 'full' or 'all' parameter
+  config.full_checks = %w(database migrations custom email cache redis resque-redis sidekiq-redis s3)
+
+  # max-age of response in seconds
+  # cache-control is public when max_age > 1 and basic_auth_username is not set
+  # You can force private without authentication for longer max_age by
+  # setting basic_auth_username but not basic_auth_password
+  config.max_age = 1
+
+  # http status code used when the ip is not allowed for the request
+  config.http_status_for_ip_whitelist_error = 403
+
+  # When redis url is non-standard
+  config.redis_url = 'redis_url'
+end

config/routes.rb

@@ -17,6 +17,8 @@
 # with BigBlueButton; if not, see <http://www.gnu.org/licenses/>.
 
 Rails.application.routes.draw do
+  get 'health_check', to: 'health_check/health_check#index'
+
   # Error routes.
   match '/404', to: 'errors#not_found', via: :all
   match '/422', to: 'errors#unprocessable', via: :all