OTP in 15 Minutes or Less

Slides for my talk given at the Philly Elixir Meetup on the OTP part of Elixir/OTP.

Transcript

1. OTP in 15 Minutes or Less Philly Elixir Meetup
 August 2016 Gavin M. Roy VP of Architecture AWeber Communications
2. Processes • Heart of Concurrency • Are light-weight independent tasks • Share nothing • Communicate via message passing • Implement a basic contract
3. Processes • Are long lived in a message loop • Can link to other processes • Can spawn other processes • Can Crash!
4. Enter OTP It’s not just what you do, it’s how you do it
5. What is OTP? • The standard library that ships with Erlang • Design principles for code structure • A core set of common patterns and behaviors
6. OTP Concepts • Applications • Collection of Modules • Runtime Structure / Processes • Supervisors • Manage Processes • gen_* Behaviors • Releases
7. Applications • Application Resource File
 Defines application modules, defaults, and required OTP applications • Application Behavior
 start/2 and stop/1 {application, name, [ {description, ""}, {vsn, "1"}, {registered, []}, {applications, [ kernel, stdlib ]}, {mod, {server, []}}, {env, []} ]}.
8. Supervisors Return a list of Child Specifications that • Defines the process IDs and MFAs • What to do if processes crashes • How to shutdown the processes • What type of processes the children are
9. Supervision Tree S W S W W S S W W W W W
10. gen_server - init/1
 - handle_call/3 
 - handle_cast/2 
 - handle_info/2 
 - terminate/2 - code_change/3
11. Other OTP Behaviors Built-In • gen_fsm (Deprecated)
 Finite State Machine • gen_statem
 Event State Machine • gen_event
 Generic event handling behavior 3rd Party Examples • gen_leader
 Distributed Master/Slave topology • gen_tcp_server
 Generic TCP Server • gen_rpc
 Scalable Multi-node RPC library
12. Releases • Bundle Application • cli control application • Hot-code swap upgrade steps
13. Questions? gmr @crad