nicta-heroku-intro

What is Heroku?

• Platform-as-a-Service providing
  • Some CPUs ('dynos')
  • Optional database (Postgres)
  • Optional add-ons
  • Load balancer in front
• Runs on AWS (US East or Europe)

Why?

• Write code, don't manage infrastructure
• Provides app management features like:
  • Rollback
  • Backups
  • Build pipelines

Supported stacks

• Ruby
• Node.js
• Python
• Clojure
• Java - with embedded servlet container
• Scala - Play or custom app
• Grails (ugh)
• ...anything you want with custom Procfile and/or build pack

What is a Dyno?

• 512MB 1 CPU or 1GB 2 CPU
• 1 free small dyno per app
• 'Unlimited' apps for free
• 'Scale out' rather than 'scale up'

Heroku databases

• Postgres with different grades

  • Free - 10k rows
  • Basic - 10M rows, $9/month
  • Prod instances from $50/month

• Can access via command line (psql) or SQL client

Add-ons

• Managed services that can be easily added on
• https://addons.heroku.com/

Traps to watch out for

Dynos change a lot

Dynos go up and down all the time

Dynos shut down if no activity

Load balancer has no server affinity

Dynos are really small...so watch your JVM!

Remember: Heroku relies on AWS (East coast or EU)

Small, stateless and resilient components!

Try something like Pingdom for pinging/monitoring

Building and starting apps

• Apps must start in < 60 seconds
• Apps must build in < 15 minutes
• Apps built in the 'cloud'
  • Include private libraries in your repo
• Easiest to push entire repos instead of subtrees
• If your app doesn't start, check the number of dynos you have assigned