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# How to find out where a method comes from.
# Learned this from Dave Thomas while teaching Advanced Ruby Studio
# Makes the case for separating method definitions into
# modules, especially when enhancing built-in classes.
module Perpetrator
  def crime
  end
end

class Fixnum

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mkdir -p /usr/local/etc/nginx/sites-{enabled,available}

File locations:

• nginx.conf to /usr/local/etc/nginx/
• default and default-ssl to /usr/local/etc/nginx/sites-available
• homebrew.mxcl.nginx.plist to /Library/LaunchDaemons/

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include Rails.application.routes.url_helpers
default_url_options[:host] = "localhost"

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Introduction

An introduction to curl using GitHub's API

The Basics

Makes a basic GET request to the specifed URI

curl https://api.github.com/users/caspyin

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import com.google.common.cache.CacheBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurer;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.guava.GuavaCache;
import org.springframework.cache.interceptor.CacheErrorHandler;
import org.springframework.cache.interceptor.CacheResolver;
import org.springframework.cache.interceptor.KeyGenerator;

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import com.google.common.cache.CacheBuilder;
import org.springframework.cache.Cache;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.guava.GuavaCache;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.concurrent.TimeUnit;

@Configuration

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Go vs. Scala (Akka) Concurrency

A comparison from 2 weeks using Go.

Actors vs. Functions

Akka's central principle is that there you have an ActorSystem which runs Actors. An Actor is defined as a class and it has a method to receive messages.

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# script used in consul to check if mysql is primary master and asynchronous slave
# v.0.1 - lefred 2018-02-16

SLAVEOFDC="dc2"
SLAVEUSER="async_repl"
SLAVEPWD="asyncpwd"

# check if we are the primary one
ROLE=$(mysql -h 127.0.0.1 -BNe "select MEMBER_ROLE from performance_schema.replication_group_members where MEMBER_HOST=@@hostname")

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# script used in consul
# the following addition to sys is required: 
#   https://gist.github.com/lefred/153448f7ea0341d6d0daa2738db6fcd8
# v.0.1 - lefred 2018-02-14


read -r mysql_primary mysql_readonly mysql_tx mysql_cert <<<$(mysql -h 127.0.0.1 -P 6446 -BNe "select * from sys.gr_member_routing_candidate_status")

if [[ "${mysql_primary}" == "YES" ]] && [[ "${mysql_readonly}" == "NO" ]]
then

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# from http://dzone.com/snippets/analyse-binary-log

# cat /bin/mylog
#!/bin/sh
# usage:
#$ mylog /mysql-bin-log/db-bin.000223
#   2132 insert into customers
#   1887 update userlog_access
#    788 insert into gn_commission
#    718 insert into con_tab