Den of Clojure | Real Projects | Jupiter

DoC-sep-2015-Jupiter.org

Den of Clojure

REAL PROJECTS

Jupiter

Den of Clojure, 2015-09-10

Ian Truslove ● @iantruslove ● Sonian.com

Topics

• Overview
• Lifecycle
• Components
• jupiterctls with Carousel defadmins
• Config with Carica
• Embedded webservers

Overview

• Sonian
• Emails
• Analytics
• Jupiter

Lifecycle and Deployment

• Jupiter: It’s Just a JAR
  • We use lein tar for packaging (very similar to uberjar)
  • lein-tar
• Shell script to start server
• jupiterctl shell script interface for shutdown (more later)
• System model:
  • One “master” per JVM
  • Thread pool for workers
  • Queue for job management (PostgreSQL)
  • Zookeeper for distributed locks

Components

For managing and composing system state

• Based on Stuart Sierra’s component
• Multimethod dispatch:
  • start
  • stop
  • status
• All state contained in one atom
• Worker system plus ad-hoc test-time systems

jupiterctls with Carousel defadmins

• Carousel runs a socket server
  • Carousel is open source
    • https://github.com/sonian/carousel
• defadmin sets up socket-invokable functions
• jupiterctl is a simple wrapper around nc
• Auto-documented via docstrings
• Interesting jupiterctls:
  • help
  • status
  • config
  • repl
  • stop

Config with Carica

• EDN config files in multiple places
• Carica is open source
  • https://github.com/sonian/carica

Embedded webservers

• Ring Jetty adapter (api)
  • Maintains its own threadpool
• Alternatives:
  • Http Kit
  • Aleph
  • Immutant 2.0

Q&A

You must got questions, right?

This document:

• http://bit.ly/1M0d3st
• https://gist.github.com/ea6f452891d8ec76f378