Gabriel Chaney gabrieljoelc

Originally published in June 2008

When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. And in the corporate/enterprise world, I often don't have access to their previous work.

To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions -- a ruby measuring stick if you will -- to select the cream of the crop that walked through our doors.

What to expect

Candidates will typically give you a range of responses based on their experience and personality. So it's up to you to decide the correctness of their answer.

Working with Dates, Times, and Timezones

Top 10 recommendations for developers

Update: tzTime (documentation) is now available seperately from Lumenize. The examples below still work because tzTime is a dependency of Lumenize and included in that package (as well as Rally's App SDK v2.0p6 or greater). However, Lumenize includes a lot more functionality around time-series and temporal model aggregations, OLAP Cube, etc. If you just want the Time object, just grab tzTime.

What's the correct query clause to get all the transactions from March? The naive answer is "2012-03-01" <= eventTimestamp <= "2012-03-31" but what if the person worked in the eastern US and wanted timezone taken into account? Then the correct answer is "2012-03-01T05" <= eventTimestamp < "2012-04-01T04". Notice how the timeshift for the beginning of March is different from the end. Getting this right is mind bendingly di

Problem: When linking to the raw version of a gist, the link changes with each revision.

Solution:

To return the first file from a gist: https://gist.github.com/[gist_user]/[gist_id]/raw/

Example: https://gist.github.com/atenni/5604522/raw/
Works even when you change the filename.

To get a file from multi–file gist: https://gist.github.com/[gist_user]/[gist_id]/raw/[file_name]

In Rails 3

NOTE: This post now lives (and kept up to date) on my blog: http://hakunin.com/rails3-load-paths

If you add a dir directly under app/

Do nothing. All files in this dir are eager loaded in production and lazy loaded in development by default.

	public class ListPostsQuery
	{
	private readonly IDocumentSession session;

	public ListPostsQuery(IDocumentSession session)
	{
	this.session = session;
	}

	public List<Post> Execute(int currentPage, int defaultPage, int pageSize, out RavenQueryStatistics stats)

	# -- coding: utf-8 --
	class EqualAttributesMatcher
	def initialize(attrs)
	@attrs = attrs
	end

	def matches?(model)
	@model = model
	@attrs.all? { \|k,v\| @model.send(k) == v }
	end

	[AutoMap(typeof(ViewModel)]
	public ActionResult View(int id)
	{
	var entity = LoadFromDatabase(id);
	return View(entity);
	}

	#!/usr/bin/env bash

	##########################################################
	#
	# This is a shell script for keeping a journal that is
	# * plaintext,
	# * time-stamped,
	# * encrypted, and
	# * edited with vim.
	#

	# You have your csv data and it looks like so... It's in a file named "my_data.csv" and we want to import it into a table named "my_things".

	"1", "Something", "0.50", "2013-05-05 10:00:00"
	"2", "Another thing", "1.50", "2013-06-05 10:30:00"

	# Now you want to import it, go to the command line and type:

	$ PGPASSWORD=PWHERE psql -h HOSTHERE -U USERHERE DBNAMEHERE -c "\copy my_things FROM 'my_data.csv' WITH CSV;"

	# Voila! It's impoted. Now if you want to wipe it out and import a fresh one, you would do this: