Terminate istio sidecar after migrations if it exists

Without this change the job never completes because the istio-proxy runs
forever. We make a request to the Istio sidecar admin port (15000) to
terminate it. If we receive a non-200 response or an exception occurs,
we print details and exit 0.

[#175367511]

Co-authored-by: Matt Royal <mroyal@vmware.com>
Co-authored-by: Travis Patterson <travisp@vmware.com>

Author: matt-royal

Procfile

@@ -3,5 +3,5 @@ local-worker:       bundle exec rake jobs:local
 api-worker:         bundle exec rake jobs:generic
 clock:              bundle exec rake clock:start
 deployment-updater: bundle exec rake deployment_updater:start
-migrate:            /bin/bash -c 'bundle exec rake db:connect && bundle exec rake db:setup_database'
+migrate:            /bin/bash -c 'bundle exec rake db:connect && bundle exec rake db:setup_database && bundle exec rake db:terminate_istio_if_exists'
 

lib/tasks/db.rake

@@ -165,6 +165,13 @@ namespace :db do
     end
   end
 
+  desc 'Terminate Istio sidecar for migration job (if one exists)'
+  task :terminate_istio_if_exists do
+    puts 'Terminating Istio sidecar'
+
+    terminate_istio_sidecar_if_exists
+  end
+
   desc 'Validate Deployments are not missing encryption keys'
   task :validate_encryption_keys do
     RakeConfig.context = :api
@@ -302,4 +309,18 @@ namespace :db do
       end
     end
   end
+
+  def terminate_istio_sidecar_if_exists
+    client = HTTPClient.new
+    response = client.request(:post, 'http://localhost:15000/quitquitquit')
+
+    unless response.code == 200
+      puts "Failed to terminate Istio sidecar. Received response code: #{response.code}"
+      return
+    end
+
+    puts 'Istio sidecar is now terminated'
+  rescue => e
+    puts "Request to Istio sidecar failed. This is expected if your kubernetes cluster does not use Istio. Error: #{e}"
+  end
 end