Artur Martins arturmartins

Setting up a Raspberry Pi as a dashboard server with Dashing

Why the heck did I do this?

I wanted to set up one of my Raspberry Pi's as a data dashboard, pushing sensor data to a web interface that's easy to digest. I decided to use Shopify's Dashing framework. Dashing is based on Sinatra, and is pretty lightweight.

Dashing does require Ruby 1.9.3 to run. In addition, it makes use of the execjs gem, which needs to have a working Javascript interpreter available. Originally, I tried to get therubyracer working, but decided to switch over to Node.js when I ran into roadblocks compiling V8.

One warning: The RPi is a very slow system compared with modern multi-core x86-style systems. It's pretty robust, but compiling all this complex software taxes the system quite a bit. Expect that it's going to take at least half a day to get everything going.

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

vimdiff cheat sheet

##git mergetool

In the middle file (future merged file), you can navigate between conflicts with ]c and [c.

Choose which version you want to keep with :diffget //2 or :diffget //3 (the //2 and //3 are unique identifiers for the target/master copy and the merge/branch copy file names).

:diffupdate (to remove leftover spacing issues)

:only (once you’re done reviewing all conflicts, this shows only the middle/merged file)

##Google Interview Questions: Product Marketing Manager

Why do you want to join Google? -- Because I want to create tools for others to learn, for free. I didn't have a lot of money when growing up so I didn't get access to the same books, computers and resources that others had which caused money, I want to help ensure that others can learn on the same playing field regardless of their families wealth status or location.
What do you know about Google’s product and technology? -- A lot actually, I am a beta tester for numerous products, I use most of the Google tools such as: Search, Gmaill, Drive, Reader, Calendar, G+, YouTube, Web Master Tools, Keyword tools, Analytics etc.
If you are Product Manager for Google’s Adwords, how do you plan to market this?
What would you say during an AdWords or AdSense product seminar?
Who are Google’s competitors, and how does Google compete with them? -- Google competes on numerous fields: --- Search: Baidu, Bing, Duck Duck Go

	// Just before switching jobs:
	// Add one of these.
	// Preferably into the same commit where you do a large merge.
	//
	// This started as a tweet with a joke of "C++ pro-tip: #define private public",
	// and then it quickly escalated into more and more evil suggestions.
	// I've tried to capture interesting suggestions here.
	//
	// Contributors: @r2d2rigo, @joeldevahl, @msinilo, @_Humus_,
	// @YuriyODonnell, @rygorous, @cmuratori, @mike_acton, @grumpygiant,

	sudo add-apt-repository ppa:pitti/postgresql
	sudo apt-get update
	sudo apt-get install postgresql-9.2 postgresql-server-dev-9.2 postgresql-contrib-9.2

	sudo su -l postgres
	psql -d template1 -p 5433
	CREATE EXTENSION IF NOT EXISTS hstore;
	CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
	service postgresql stop
	/usr/lib/postgresql/9.2/bin/pg_upgrade -b /usr/lib/postgresql/9.1/bin -B /usr/lib/postgresql/9.2/bin -d /var/lib/postgresql/9.1/main/ -D /var/lib/postgresql/9.2/main/ -O "-c config_file=/etc/postgresql/9.2/main/postgresql.conf" -o "-c config_file=/etc/postgresql/9.1/main/postgresql.conf"

	f = open('user.yaml')

	dataMap = yaml.load(f)

	f.close()
	print ""
	print "=-----------="
	print "dataMap is a ", type(dataMap), dataMap
	print "=-----------="
	print "main items are", type(dataMap['main']), dataMap['main']

	-- show running queries (pre 9.2)
	SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
	FROM pg_stat_activity
	WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
	ORDER BY query_start desc;

	-- show running queries (9.2)
	SELECT pid, age(clock_timestamp(), query_start), usename, query
	FROM pg_stat_activity
	WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'

	# First attempting to use Capybara directly, you will ran into issues when trying to set HTTP header.
	# Using Basic HTTP Authentication requires that we needed to set the header.
	# Also we need to set the Content-Type and Accept headers to ensure that Rails handles the input and output correctly.
	# When using Rack, Capybara delegates request and response handling down to Rack::Test.
	# So I used Rack::Test directly in my step definitions, and it works.
	# Rack::Test has a module called Rack::Test::Methods that can be mixed into a class to provide it
	# with methods for get, post, put, delete as well as last_request, last_response, header and more.
	# I mixed Rack::Test::Methods into the Cucumber world at the top of our API steps file like so:

	##############################

	access_key_id: xxx
	secret_access_key: yyy