• 4.7 Script a deployment
  • Learning Objectives
  • EXERCISE: Modify Capistrano script.
  • EXERCISE: Modify Capistrano Script (OPTIONAL: Ruby)

4.7 Script a deployment

Learning Objectives

By the end of this lesson you will be able to:

• Write a deployment script in Capistrano.

EXERCISE: Modify Capistrano script.

1. Go to the deployment/config directory.

   cd /home/ec2-user/continuous_integration_example/software/deployment/config

2. Create a new file called mydeploy.rb

   “` $ sudo vim mydeploy.rb

   “`

3. Insert the contents of the code example below into the mydeploy.rb. Be sure to replace the 29 in cd29 with your userid.

   “` require ‘rubygems’ require ‘aws-sdk’ load ‘/usr/share/tomcat6/scripts/config/aws.config’

   sdb = AWS::SimpleDB.new

   set :sdb_domain, “cd29”

   set :domain do item = sdb.domains[“#{sdb_domain}”].items[‘parameters’] item.attributes[‘ip_address’].values[0].to_s end

   set :artifact_bucket do item = sdb.domains[“#{sdb_domain}”].items[‘parameters’] item.attributes[‘artifact_bucket’].values[0].to_s end

   set :ip_address do item = sdb.domains[“#{sdb_domain}”].items[‘parameters’] item.attributes[‘ip_address’].values[0].to_s end

   set :user, “ec2-user” set :use_sudo, false set :deploy_to, “/usr/share/tomcat6/webapps” set :artifact, “brewery.war” set :artifact_url, “https://s3.amazonaws.com/#{artifact_bucket}/#{artifact}” set :ssh_options, { :forward_agent => true }

   set :application, domain

   role :web, domain role :app, domain role :db, domain, :primary => true

   set :deploy_via, :remote_cache

   def get_binding binding # So that everything can be used in templates generated for the servers end

   def from_template(file) require ‘erb’ template = File.read(File.join(File.dirname(FILE), “..”, file)) result = ERB.new(template).result(self.get_binding) end

   namespace :deploy do

   task :setup do run “sudo chown -R tomcat:tomcat #{deploy_to}” run “sudo service tomcat6 stop” end

   task :deploy do run “cd #{deploy_to} && sudo rm -rf brewery* && sudo wget #{artifact_url}” end

   desc “Restart Application” task :restart, :roles => :app do run “sudo service tomcat6 restart” end

   after “deploy:setup”, “deploy:deploy” after “deploy:deploy”, “deploy:restart” end “`

   Save and close the mydeploy.rb file

4. Add the file in Git

   “` $ git add .

   “`

5. Commit the file to Git

   “` $ git commit -m “Created deployment script”

   “`

6. Push it to the Git master.

   “` $ git push

   “`

7. Modify your Jenkins Deploy job to run your version: mydeploy.rb. Run a Build job, Environment job and the Deploy job. Verify the application is deployed to the environment.

EXERCISE: Modify Capistrano Script (OPTIONAL: Ruby)

1. From the AWSCLI instance, change directory to devopsinthecloud.

2. Open the file as shown below.

   “` $ sudo vim deploy.rb

   “`

3. A list of some of the deploy tasks is provided below.

   “` deploy:setup deploy:deploy deploy:bundle_install deploy:db_migrate deploy:restart

   “`

4. Capify is run in the jenkins.template

5. You can also find these files by going to https://raw.github.com/stelligent/continuous_integration_example/master/deployment/config/deploy.rb.
6. Review the Deployment Jenkins job.
7. Make a modification to the contents of the file and save it.

8. Add the file in Git

   “` $ git add .

   “`

9. Commit the file to Git

   “` $ git commit -m “Modified deployment script”

   “`

10. Push it to the Git master.

    “` $ git push

    “`