Add option to check for deprecated stacks in pre-start rake task

jobs/cloud_controller_ng/spec

@@ -55,6 +55,7 @@ templates:
   shutdown_drain.rb.erb: bin/shutdown_drain
   ruby_version.sh.erb: bin/ruby_version.sh
   seed_db.sh.erb: bin/seed_db
+  stack_check.sh.erb: bin/stack_check
   setup_local_blobstore.sh.erb: bin/setup_local_blobstore.sh
   stacks.yml.erb: config/stacks.yml
   uaa_ca.crt.erb: config/certs/uaa_ca.crt
@@ -226,6 +227,7 @@ provides:
   - cc.experimental.use_puma_webserver
   - cc.experimental.use_redis
   - cc.app_log_revision
+  - cc.deprecated_stacks
 
 consumes:
 - name: database
@@ -467,6 +469,11 @@ properties:
   cc.default_stack:
     default: "cflinuxfs4"
     description: "The default stack to use if no custom stack is specified for an app."
+  cc.deprecated_stacks:
+    description: |
+      List of deprecated/unsupported stack names. 
+      If a stack in this list exists in the database, the Cloud Controller bootstrap VM will fail to start. 
+      The only exception to this behavior occurs when the deprecated stack is explicitly listed in cc.stacks.
 
   cc.staging_upload_user:
     description: "User name used to access internal endpoints of Cloud Controller to upload files when staging"

jobs/cloud_controller_ng/templates/pre-start.sh.erb

@@ -121,6 +121,12 @@ function start_bosh_dns_or_consul {
   fi
 }
 
+function stack_check() {
+  pushd "${CC_PACKAGE_DIR}/cloud_controller_ng" > /dev/null
+    chpst -u vcap:vcap "${SCRIPT_DIR}/stack_check"
+  popd > /dev/null
+}
+
 function start_consul_agent {
   # Start the consul agent so we can connect to a database url provided by consul dns
   if [ -f /var/vcap/jobs/consul_agent/bin/agent_ctl ]; then
@@ -136,6 +142,7 @@ function main {
   start_bosh_dns_or_consul
   setup_directories
   <% if spec.bootstrap && p('cc.run_prestart_migrations') %>
+  stack_check
   perform_migration
   seed_db
     <% if p('cc.database_encryption.skip_validation') %>

jobs/cloud_controller_ng/templates/stack_check.sh.erb

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+
+set +e
+set -x
+
+CC_PACKAGE_DIR="/var/vcap/packages/cloud_controller_ng"
+export BUNDLE_GEMFILE="${CC_PACKAGE_DIR}/cloud_controller_ng/Gemfile"
+export STACKS_YML="/var/vcap/jobs/cloud_controller_ng/config/stacks.yml"
+export NRCONFIG=/var/vcap/jobs/cloud_controller_ng/config/newrelic.yml
+
+function stack_check {
+  bundle exec rake stacks:stack_check
+  exit $?
+}
+
+function main {
+  stack_check
+}
+
+main
+
+exit 0

jobs/cloud_controller_ng/templates/stacks.yml.erb

@@ -1,2 +1,3 @@
 default: <%= p("cc.default_stack") %>
 stacks: <%= p("cc.stacks", []).to_yaml.gsub("---", "") %>
+deprecated_stacks: <%= p("cc.deprecated_stacks", []).to_yaml.gsub("---", "") %>