Christopher Young krsyoung

Query Performance Monitoring

We've had the case where a seemingly small change in a query (such as adding a .join() clause) actually caused us a large load-related headache when run multiple times by our users in production. To avoid this issue in future iterations we now use (rack-mini-profiler)[https://github.com/MiniProfiler/rack-mini-profiler] to help us measure our queries in development! The profiler will give you a file-by-file, query-by-query analysis of your page load times and flag expensive queries.

After installing certbot:

sudo service nginx stop
sudo ./certbot-auto certonly --standalone -d sub.example.com --standalone-supported-challenges http-01
sudo service nginx start

Modified the ngnix site conf:

server {

listen 80;

Generate openssl keys:

openssl req -x509 -nodes -newkey rsa:2048 -keyout mysqldump-key.priv.pem -out mysqldump-key.pub.pem

Create a mysql default file:

# ~/.mysqldump
[mysqldump]
host = host.here.com

HTTP Streaming (or Chunked vs Store & Forward)

The standard way of understanding the HTTP protocol is via the request reply pattern. Each HTTP transaction consists of a finitely bounded HTTP request and a finitely bounded HTTP response.

However it's also possible for both parts of an HTTP 1.1 transaction to stream their possibly infinitely bounded data. The advantages is that the sender can send data that is beyond the sender's memory limit, and the receiver can act on

	#postgresql setup

	ssh -i ~/.ssh/id_rsa root@<domain>
	dokku postgres:connect <db>

	psql=# SHOW config_file;
	-> /var/lib/postgresql/data/postgresql.conf
	psql=# \q

	docker ps

	# Creating a Digital Ocean droplet running Rails + Postgres with persistant storage and https
	#--------------------------------------------------------------------------------------------

	# For your ctrl-D pleasure...
	# SERVER_IP
	# APP_NAME
	# RAILS_SECRET (generate with `rails secret`)
	# ADMIN_EMAIL

	<%# Put this code snippet between the <head></head>-tags in your application layout and %>
	<%# replace 'UA-XXXXXXXX-X' with your own unique Google Analytics Tracking ID %>

	<%# ... %>
	<head>
	<%# ... %>
	<% if Rails.env.production? %>
	<script type="text/javascript">
	(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]\|\|function(){
	(i[r].q=i[r].q\|\|[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),

	# Call scopes directly from your URL params:
	#
	# @products = Product.filter(params.slice(:status, :location, :starts_with))
	module Filterable
	extend ActiveSupport::Concern

	module ClassMethods

	# Call the class methods with names based on the keys in <tt>filtering_params</tt>
	# with their associated values. For example, "{ status: 'delayed' }" would call

	var gulp = require('gulp'),
	gutil = require('gulp-util'),
	stylus = require('gulp-stylus'),
	uglify = require('gulp-uglify'),
	jade = require('gulp-jade'),
	concat = require('gulp-concat'),
	livereload = require('gulp-livereload'),
	tinylr = require('tiny-lr'),
	express = require('express'),
	app = express(),

	// layout file

	<body>
	<div class="container">

	<%= flash_messages %>

	<%= yield %>
	</div><!-- /container -->
	</body>