Abe Voelker abevoelker

Rough cert-manager GKE install instructions:

export PROJECT_ID="cert-manager-$(openssl rand -hex 6)"
export [email protected]

gcloud projects create --set-as-default $PROJECT_ID
gcloud compute addresses create ipv4-address --global --ip-version IPV4
gcloud services enable compute.googleapis.com
gcloud services enable container.googleapis.com

Constraints - super important for ensuring data integrity (bad data can't get into the DB)
- UNIQUE indexes to ensure a record is unique on one or more column values
- CHECK constraints allow some basic logic you can use (https://www.postgresql.org/docs/current/static/ddl-constraints.html)
- FOREIGN KEY (FK)'s - very important for ensuring referential integrity. Lets the database knows about relations between tables, and what to do if a record is deleted or updated (how related tables should change) - e.g. should related records be deleted (ON DELETE CASCADE)
- Anything more complicated than the above, you'll need to write a TRIGGER (https://www.postgresql.org/docs/current/static/sql-createtrigger.html)
  - Learning/using PL/pgSQL will be very important here (https://www.postgresql.org/docs/9.6/static/plpgsql.html). Although you can write triggers in other languages w/ extensions, such as Python or JavaScript, but usually you only do that if you need a specific library or something.
Indexes - i

How annoying is it that Rails doesn't do what you tell it, but tries to be smart? Trying to use custom DB logic in a Rails migration:

create_table :foos do |t|
  t.timestamp :inserted_time, null: false, default: 'now()'
end

Results in this:

	require "typhoeus"

	class OneSignal
	class << self
	[:app_id, :api_key, :timeout, :connecttimeout].each do \|opt\|
	define_method(:"#{opt}=") {\|val\| instance_variable_set(:"@#{opt}", val)}
	define_method(opt) { begin; instance_variable_get(:"@#{opt}"); rescue NameError; nil; end }
	end
	end

	{-
	This code shows how to check if a type-level list contains a given type.
	It first shows the approach required for older versions of GHC (< 7.6.x)
	and then a version using closed type families supported in GHC 7.8.1 and greater.
	-}

	{-# LANGUAGE FlexibleContexts #-}
	{-# LANGUAGE UndecidableInstances #-}
	{-# LANGUAGE FlexibleInstances #-}
	{-# LANGUAGE MultiParamTypeClasses #-}

	import java.security._
	import java.net.URL
	import javax.net.ssl.{KeyManagerFactory, TrustManagerFactory}
	import org.apache.http.conn.ssl.SSLSocketFactory
	import org.apache.http.conn.scheme.Scheme
	import dispatch._

	// Gist trait for doing SSL with mutual certificate exchange using dispatch.
	// This works without having to set up global JDK-wide keystore and truststore files.
	//

	scala> val scores = Map("a" -> 100, "b" -> 101)
	scores: scala.collection.immutable.Map[String,Int] = Map(a -> 100, b -> 101)

	scala> scores.filter { case (_, i) => i > 100 }
	java.lang.AssertionError: assertion failed: List(value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp, value _2$mcI$sp)
	at scala.reflect.internal.Symbols$Symbol.suchThat(Symbols.scala:1916)
	at scala.tools.nsc.transform.SpecializeTypes$$anon$2.matchingSymbolInPrefix$1(SpecializeTypes.scala:1460)
	at scala.t

	### Keybase proof

	I hereby claim:

	* I am abevoelker on github.
	* I am abevoelker (https://keybase.io/abevoelker) on keybase.
	* I have a public key whose fingerprint is 7C75 A5F5 E608 E133 4314 7A24 65A8 0811 BC6A 8D92

	To claim this, I am signing this object:

	# This is an example of the Stack Exchange Tier 1 HAProxy config
	# The only things that have been changed from what we are running are:
	# 1. User names have been removed
	# 2. All Passwords have been remove
	# 3. IPs have been changed to use the example/documentation ranges
	# 4. Rate limit numbers have been changed to randome numbers, don't read into them

	userlist stats-auth
	group admin users $admin_user
	user $admin_user insecure-password $some_password

	data Tree = Empty
	\| Leaf Int
	\| Node Tree Tree