kaktumar

A minimal HTTP server in python. It sends a JSON Hello World for GET requests, and echoes back JSON for POST requests.

python server.py 8009
Starting httpd on port 8009...

curl http://localhost:8009
{"received": "ok", "hello": "world"}

ANNOUNCEMENT

I have moved this over to the Tech Interview Cheat Sheet Repo and has been expanded and even has code challenges you can run and practice against!

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Opening and closing an SSH tunnel in a shell script the smart way

I recently had the following problem:

From an unattended shell script (called by Jenkins), run a command-line tool that accesses the MySQL database on another host.
That tool doesn't know that the database is on another host, plus the MySQL port on that host is firewalled and not accessible from other machines.

We didn't want to open the MySQL port to the network, but it's possible to SSH from the Jenkins machine to the MySQL machine. So, basically you would do something like

ssh -L 3306:localhost:3306 remotehost

What

Roll your own iPython Notebook server with Amazon Web Services (EC2) using their Free Tier.

What are we using? What do you need?

An active AWS account. First time sign-ups are eligible for the free tier for a year
One Micro Tier EC2 Instance
With AWS we will use the stock Ubuntu Server AMI and customize it.
Anaconda for Python.
Coffee/Beer/Time

Node.js - npm Cheat Sheet

(Full description and list of commands at - https://npmjs.org/doc/index.html)

List of less common (however useful) NPM commands

Prepand ./bin to your $PATH

Make sure to export your local $PATH and prepand relative ./node_modules/.bin/:

	#!/bin/bash
	# Retrieve AWS instrance's commonly used metadata. Require curl.
	# ./get-metadata help
	# ./get-metadata id

	# Input is case insensitive; format to uppper case to generate self-help page.
	info=${1^^}
	meta_data_url=http://169.254.169.254/latest/meta-data/
	roleProfile=$(curl -s http://169.254.169.254/latest/meta-data/iam/info \
	\| grep -Eo 'instance-profile/([a-zA-Z.-]+)' \| sed 's#instance-profile/##')

	/*

	This script counts all photos that are available on Flickr and Panoramio for a specific geo fence and returns a JSON object with the data.
	For convenience it's embedded in a little node.js server so that you can upload it to your server and use it as an API.

	Here's an example url with all query attributes prefilled. Please use your own Flickr API key!
	The location is the Berlin TV Tower (http://en.wikipedia.org/wiki/Fernsehturm_Berlin)

	Example URL: http://piccounter-philippschmitt.rhcloud.com/?lat=52.520732&lon=13.409537&latRes=0.00015&lonRes=0.0003&flickrKey=60d03369d3e92b4578c8f2df2de5af66

	# ssh(1) obtains configuration data from the following sources in the following order:
	#
	# 1. command-line options
	# 2. user's configuration file (~/.ssh/config)
	# 3. system-wide configuration file (/etc/ssh/ssh_config)
	#
	# For each parameter, the first obtained value will be used. The configuration files contain sections separated
	# by “Host” specifications, and that section is only applied for hosts that match one of the patterns given in the
	# specification. The matched host name is the one given on the command line.
	#

	#!/bin/bash

	# This is a script to create a video from series of JPEG images
	# Call it in a folder full of JPEGs that you want to turn into a video.
	# Written on 2013-01-08 by Philipp Klaus <philipp.l.klaus →AT→ web.de>.
	# Check <https://gist.github.com/4572552> for newer versions.

	# Resources
	# * http://www.itforeveryone.co.uk/image-to-video.html
	# * http://spielwiese.la-evento.com/hokuspokus/index.html