sunnycmf

When first confronted with node.js, you are not only presented with a completely new programming environment. You also encounter what is often referred to as callback hell accompanied by weird unfamiliar programming patterns. One of these is the way node treats callback functions.

The following post explains the conventions that node.js uses for its callback patterns (referred to as Continuation-passing style) and how you should implement them in order to comply.

First argument is an error object pattern

Node expects - almost - all callback functions to accept an Error object as the first argument. If no error occurred, the first argument should be null. If you use inline anonymous functions, this is a typical code snippet that you will encounter using node:

// include the filesystem module
var fs = require('fs');

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-- credit to Akom's Tech Ruminations
-- http://tech.akom.net/archives/36-Creating-A-Basic-Date-Dimension-Table-in-MySQL.html
CREATE TABLE IF NOT EXISTS time_d  (
    time_id INT NOT NULL auto_increment,
    fulltime time,
    hour int,
    minute int,
    second int,
    ampm varchar(2),
    PRIMARY KEY(time_id)

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-- Credit to http://www.dwhworld.com/2010/08/date-dimension-sql-scripts-mysql/
-- Small-numbers table
DROP TABLE IF EXISTS numbers_small;
CREATE TABLE numbers_small (number INT);
INSERT INTO numbers_small VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);

-- Main-numbers table
DROP TABLE IF EXISTS numbers;
CREATE TABLE numbers (number BIGINT);
INSERT INTO numbers

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Setup Mac OS X Mountain Lion or Mavericks

Edit: I few months ago I got a new laptop and did the same thing on Mavericks.

I just replaced the hard drive of my mbp and decided to do a clean install of Mountain Lion (10.8.5) since I was still using Snow Leopard (10.6.8).

I kinda regret for not using Boxen to automate the

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System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

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Nice answer on stackoverflow to the question of when to use one or the other content-types for POSTing data, viz. application/x-www-form-urlencoded and multipart/form-data.

“The moral of the story is, if you have binary (non-alphanumeric) data (or a significantly sized payload) to transmit, use multipart/form-data. Otherwise, use application/x-www-form-urlencoded.”

---

Matt Bridges' answer in full:

The MIME types you mention are the two Content-Type headers for HTTP POST requests that user-agents (browsers) must support. The purpose of both of those types of requests is to send a list of name/value pairs to the server. Depending on the type and amount of data being transmitted, one of the methods will be more efficient than the other. To understand why, you have to look at what each is doing

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mr	Marathi
bs	Bosnian
ee_TG	Ewe (Togo)
ms	Malay
kam_KE	Kamba (Kenya)
mt	Maltese
ha	Hausa
es_HN	Spanish (Honduras)
ml_IN	Malayalam (India)
ro_MD	Romanian (Moldova)

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<?php
class PassAPI extends Plugin
{
	# Registration
	# register a device to receive push notifications for a pass
	#
	# POST /v1/devices/<deviceID>/registrations/<typeID>/<serial#>
	# Header: Authorization: ApplePass <authenticationToken>
	# JSON payload: { "pushToken" : <push token, which the server needs to send push notifications to this device> }
	#

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PSQL

Magic words:

psql -U postgres

If run with -E flag, it will describe the underlaying queries of the \ commands (cool for learning!).

Most \d commands support additional param of __schema__.name__ and accept wildcards like *.*

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Mac OSX softwares and env setup

install homebrew & cask

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
brew install caskroom/cask/brew-cask
brew tap caskroom/versions
brew update && brew upgrade brew-cask && brew cleanup && brew cask cleanup

Dev tools