chourobin

NB: Originally courtesy of http://blog.taggesell.de/index.php?/archives/73-Managing-Amazon-EC2-SSH-login-and-protecting-your-instances.html

Managing Amazon EC2 - SSH login and protecting your instances

How to log into your freshly fired-up instances and how to secure ssh access
(works under Linux and Mac OS, under Windows with Cygwin)

First time you want to log into a newly started instance you appear to have the chicken-and-egg problem: how to log in when you do not know the root password? Luckily Amazon devised a comfortable way to circumvent this: your Key Pairs. these are not to be confused with the „Access Key IDs“ on the Access Identifier web page and they are neither the X509 certificates. These Key pairs are automatically generated the first time you log into the web console and you can only download its private part. Store it in your ~/.ssh directory. In case you missed the download or don't know where you've put it AND you don't have any instances running, just generate and download a new one. 

chourobin

var QcValueConverter = {
  tensionFromQcValue: function(qcValue) {
    return (qcValue - 30.0) * 3.62 + 194.0;
  },

  qcValueFromTension: function(tension) {
    return (tension - 194.0) / 3.62 + 30.0;
  },

  frictionFromQcValue: function(qcValue) {

chourobin

# NullStorage provider for CarrierWave for use in tests.  Doesn't actually
# upload or store files but allows test to pass as if files were stored and
# the use of fixtures.
class NullStorage
  attr_reader :uploader

  def initialize(uploader)
    @uploader = uploader
  end

chourobin

    # encoding : utf-8
    require 'openssl'
    require 'digest/sha1'
    require 'base64'
    
    module Aws
      extend self
      def signed_url(path, expire_date)
        digest = OpenSSL::Digest::Digest.new('sha1')
        can_string = "GET\n\n\n#{expire_date}\n/#{S3_BUCKET}/#{path}"

chourobin

Studying for a Tech Interview Sucks, so Here's a Cheat Sheet to Help

This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.

Data Structure Basics

###Array ####Definition:

• Stores data elements based on an sequential, most commonly 0 based, index.
• Based on tuples from set theory.

chourobin

// in a UITableViewController (or any other view controller with a UITableView)

- (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator
{
    UIView *header = [[UIView alloc] initWithFrame:CGRectMake(0, 0, size.width, 0)];
    header.translatesAutoresizingMaskIntoConstraints = NO;
    
    // [add subviews and their constraints to header]

    NSLayoutConstraint *headerWidthConstraint = [NSLayoutConstraint 

chourobin

@interface UIButton (VerticalLayout)  

- (void)centerVerticallyWithPadding:(float)padding;  
- (void)centerVertically;  

@end  

chourobin

import Foundation

class StateMachine <P: StateMachineDelegateProtocol> {
    private unowned let delegate: P
    
    private var _state: P.StateType {
        didSet{
            delegate.didTransitionFrom(from: oldValue, to: _state)
        }

chourobin

{ fontWeight: '100' }, // Thin
{ fontWeight: '200' }, // Ultra Light
{ fontWeight: '300' }, // Light
{ fontWeight: '400' }, // Regular
{ fontWeight: '500' }, // Medium
{ fontWeight: '600' }, // Semibold
{ fontWeight: '700' }, // Bold
{ fontWeight: '800' }, // Heavy
{ fontWeight: '900' }, // Black

chourobin

//
//  ViewController.m
//  AVPlayerCaching
//
//  Created by Anurag Mishra on 5/19/14.
//  Sample code to demonstrate how to cache a remote audio file while streaming it with AVPlayer
//

#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>