Code Talk Notes - Librato and Ironbroker

Librato Update

Librato has two stats types: counter vs gauge

When using counter (aka #send_increment), be sure to set summary function to sum and check Service-Side Aggregation.

Librato counter

Ironbroker Refactor

Payload == immutable
State == mutable

Validation for each source

RabbitMq handler - rescue channel failure by creating new channel

begin
  # do bunny stuff
  # if channel closes, rescue
rescue
  @channel = @bunny.create_channel
  # bunny keeps hopping
end

Oj: much more efficient JSON parser

Checkout Source model for some cool meta-programming

New Hierarchy Builder

Structure determined by depth level

Query uses Postgres’s WITH RECURSIVE method

  • give it an initial SELECT statement which is run once
  • give it another SELECT statment that it calls recursively until it runs out of results
  • then combines the SELECT statement

Holds a path array while building, so you can see how you got to your final result

Test failures were a nightmare, but solved by creating a rollout_helper support method.

Written on September 10, 2015