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#!/usr/bin/env bash

# Simple move this file into your Rails `script` folder. Also make sure you `chmod +x puma.sh`.
# Please modify the CONSTANT variables to fit your configurations.

# The script will start with config set by $PUMA_CONFIG_FILE by default

PUMA_CONFIG_FILE=config/puma.rb
PUMA_PID_FILE=tmp/pids/puma.pid
PUMA_SOCKET=tmp/sockets/puma.sock

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check process sidekiq_01
  with pidfile /path/to/app/current/tmp/pids/sidekiq.pid
  start program = "/bin/sh -c 'cd /path/to/app/current; PATH=bin:/path/to/rbenv/shims:/path/to/rbenv/bin:$PATH nohup bundle exec sidekiq -e production -i 0 -P tmp/pids/sidekiq.pid >> log/sidekiq.log 2>&1 &'" as uid app_user and gid app_group with timeout 90 seconds
  stop program = "/bin/sh -c 'cd /path/to/app/current; PATH=bin:/path/to/rbenv/shims:/path/to/rbenv/bin:$PATH bundle exec sidekiqctl stop tmp/pids/sidekiq.pid'" as uid app_user and gid app_group with timeout 90 seconds
  if totalmem is greater than 500 MB for 2 cycles then restart # eating up memory?
  group sidekiq

check process sidekiq_02
  with pidfile /path/to/app/current/tmp/pids/sidekiq.pid-1
  start program = "/bin/sh -c 'cd /path/to/app/current; PATH=bin:/path/to/rbenv/shims:/path/to/rbenv/bin:$PATH nohup bundle exec sidekiq -e production -i 1 -P tmp/pids/sidekiq.pid-1 >> log/sidekiq.log 2>&1 &'" as uid app_user and gid app_group with timeout 90 seconds

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# this monit config goes in /etc/monit/conf.d

check process puma_master
  with pidfile  /data/myapp/current/tmp/puma.pid
  start program = "/etc/monit/scripts/puma start"
  stop program = "/etc/monit/scripts/puma stop" 
  group myapp

check process puma_worker_0
  with pidfile /data/myapp/current/tmp/puma_worker_0.pid

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My largest Sidekiq application had a memory leak and I was able to find and fix it in just few hours spent on analyzing Ruby's heap. In this post I'll show my profiling setup.

As you might know Ruby 2.1 introduced a few great changes to ObjectSpace, so now it's much easier to find a line of code that is allocating too many objects. Here is great post explaining how it's working.

I was too lazy to set up some seeding and run it locally, so I checked that test suite passes when profiling is enabled and pushed debugging to production. Production environment also suited me better since my jobs data can't be fully random generated.

So, in order to profile your worker, add this to your Sidekiq configuration:

if ENV["PROFILE"]

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# read more at https://terrty.net/2014/ssl-tls-in-nginx/
# latest version on https://gist.github.com/paskal/628882bee1948ef126dd/126e4d1daeb5244aacbbd847c5247c2e293f6adf
# security test score: https://www.ssllabs.com/ssltest/analyze.html?d=terrty.net
# your nginx version might not have all directives included, test this configuration before using in production against your nginx:
# $ nginx -c /etc/nginx/nginx.conf -t

server {
        # public key, contains your public key and class 1 certificate, to create:
        # (example for startssl)
        # $ (cat example.com.pem & wget -O - https://www.startssl.com/certs/class1/sha2/pem/sub.class1.server.sha2.ca.pem) | tee -a /etc/nginx/ssl/domain.pem > /dev/null

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# lib/custom_logger.rb
class CustomLogger < Logger
  def format_message(severity, timestamp, progname, msg)
    "#{timestamp.to_formatted_s(:db)} #{severity} #{msg}\n"
  end
end

logfile = File.open("#{Rails.root}/log/custom.log", 'a')  # create log file
logfile.sync = true  # automatically flushes data to file
CUSTOM_LOGGER = CustomLogger.new(logfile)  # constant accessible anywhere

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ruby -v jruby 9.0.1.0 (2.2.2) 2015-09-02 583f336 OpenJDK 64-Bit Server VM 24.79-b02 on 1.7.0_79-b14 +jit [linux-amd64]
server puma-2.14.0-java
rails -v Rails 4.2.4

NoMethodError (undefined method `names' for nil:NilClass):
vendor/bundle/jruby/2.2.0/gems/actionpack-4.2.4/lib/action_dispatch/journey/router.rb:116:in `block in find_routes'
  org/jruby/RubyArray.java:2332:in `map!'
  vendor/bundle/jruby/2.2.0/gems/actionpack-4.2.4/lib/action_dispatch/journey/router.rb:113:in `find_routes'
  vendor/bundle/jruby/2.2.0/gems/actionpack-4.2.4/lib/action_dispatch/journey/router.rb:30:in `serve'
  vendor/bundle/jruby/2.2.0/gems/actionpack-4.2.4/lib/action_dispatch/routing/route_set.rb:821:in `call'

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Steps to install and run PostgreSQL 9.2 using Homebrew (Mac OS X)
(if you aren't using version 9.1.5, change line 6 with the correct version)

1. launchctl unload -w ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
2. mv /usr/local/var/postgres /usr/local/var/postgres91
3. brew update
4. brew upgrade postgresql
5. initdb /usr/local/var/postgres -E utf8
6. pg_upgrade -b /usr/local/Cellar/postgresql/9.1.5/bin -B /usr/local/Cellar/postgresql/9.2.0/bin -d /usr/local/var/postgres91 -D /usr/local/var/postgres
7. cp /usr/local/Cellar/postgresql/9.2.0/homebrew.mxcl.postgresql.plist ~/Library/LaunchAgents/

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ActiveRecord cheat sheet / EXAMPLES

INSTALL 
=======  
$ gem install activerecord
in GEMFILE: gem ‘activerecord’

REQUIRE 
=======  
require ‘active_record’

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How to install PhantomJS on Ubuntu

Version: 1.9.8

Platform: x86_64

First, install or update to the latest system software.

sudo apt-get update
sudo apt-get install build-essential chrpath libssl-dev libxft-dev