Add capistrano tasks to take a node off the load balancer. (#291)

* Add capistrano tasks to take a node off the load balancer.

Closes #290

* Match CircleCI config to Ruby version

.circleci/config.yml

@@ -31,7 +31,7 @@ jobs:
     working_directory: ~/orcid_princeton
     docker:
       - &ruby_docker
-        image: cimg/ruby:3.2-browsers
+        image: cimg/ruby:3.2.5-browsers
         environment:
           RAILS_ENV: test
     steps:
@@ -40,7 +40,8 @@ jobs:
       - install_dependencies
       - persist_to_workspace:
           root: &root '~/orcid_princeton'
-          paths: '*'
+          paths: 
+            - '*'
 
   rubocop:
     working_directory: *root
@@ -57,7 +58,7 @@ jobs:
     # We don't actually need any of the ruby environment to lint JS... but use what we have for now.
     working_directory: ~/orcid_princeton
     docker:
-      - image: cimg/ruby:3.2-browsers
+      - image: cimg/ruby:3.2.5-browsers
         environment:
           RAILS_ENV: test
     steps:
@@ -94,7 +95,8 @@ jobs:
           command: COVERALLS_REPO_TOKEN=$COVERALLS_REPO_TOKEN bundle exec rspec --format progress
       - persist_to_workspace:
           root: *root
-          paths: 'coverage'
+          paths: 
+            - 'coverage'
       - store_artifacts:
           path:
             /home/circleci/orcid_princeton/tmp/capybara

Gemfile

@@ -9,7 +9,8 @@ gem "rails", "~> 7.1.0"
 gem "bcrypt_pbkdf"
 gem "bootsnap", require: false
 gem "ed25519"
-gem "health-monitor-rails"
+# Pinning to 12.4.0 due to Rails 7.1 compatibility issue in 12.4.1
+gem "health-monitor-rails", "12.4.0"
 gem "honeybadger"
 gem "httparty"
 gem "isni"

Gemfile.lock

@@ -227,7 +227,7 @@ GEM
       activesupport (>= 6.1)
     hashdiff (1.1.1)
     hashie (5.0.0)
-    health-monitor-rails (12.1.0)
+    health-monitor-rails (12.4.0)
       railties (>= 6.1)
     honeybadger (5.8.0)
     httparty (0.22.0)
@@ -543,7 +543,7 @@ DEPENDENCIES
   ed25519
   factory_bot_rails
   ffaker
-  health-monitor-rails
+  health-monitor-rails (= 12.4.0)
   honeybadger
   httparty
   isni

config/deploy.rb

@@ -15,6 +15,37 @@
 # Must match `ViteRuby.config.public_output_dir`, which by default is 'vite'
 set :assets_prefix, "vite"
 
+namespace :application do
+  # You can/ should apply this command to a single host
+  # cap --hosts=orcid-staging1.princeton.edu staging application:remove_from_nginx
+  desc "Marks the server(s) to be removed from the loadbalancer"
+  task :remove_from_nginx do
+    count = 0
+    on roles(:app) do
+      count += 1
+    end
+    if count > (roles(:app).length / 2)
+      raise "You must run this command on no more than half the servers utilizing the --hosts= switch"
+    end
+    on roles(:app) do
+      within release_path do
+        execute :touch, "public/remove-from-nginx"
+      end
+    end
+  end
+
+  # You can/ should apply this command to a single host
+  # cap --hosts=orcid-staging1.princeton.edu staging application:serve_from_nginx
+  desc "Marks the server(s) to be added back to the loadbalancer"
+  task :serve_from_nginx do
+    on roles(:app) do
+      within release_path do
+        execute :rm, "-f public/remove-from-nginx"
+      end
+    end
+  end
+end
+
 # Workaround for this issue: https://github.com/capistrano/rails/issues/235
 Rake::Task["deploy:assets:backup_manifest"].clear_actions
 Rake::Task["deploy:assets:restore_manifest"].clear_actions

config/initializers/health_monitor.rb

@@ -3,17 +3,21 @@
   HealthMonitor.configure do |config|
     config.cache
 
-    config.add_custom_provider(OrcidApiStatus)
+    config.add_custom_provider(OrcidApiStatus).configure do |provider_config|
+      # set the orcid API check to not critical
+      provider_config.critical = false
+    end
 
-    # set the orcid API check to no critical
-    config.providers.last.configuration.critical = false
+    config.file_absence.configure do |file_config|
+      file_config.filename = "public/remove-from-nginx"
+    end
 
     # Make this health check available at /health
     config.path = :health
 
     config.error_callback = proc do |e|
       Rails.logger.error "Health check failed with: #{e.message}"
-      Honeybadger.notify(e)
+      Honeybadger.notify(e) unless e.is_a? HealthMonitor::Providers::FileAbsenceException
     end
   end
 end