Arthur Alvim arthuralvim

(This gist is pretty old; I've written up my current approach to the Pyramid integration on this blog post, but that blog post doesn't go into the transactional management, so you may still find this useful.)

Fast and flexible unit tests with live Postgres databases and fixtures

I've created a Pyramid scaffold which integrates Alembic, a migration tool, with the standard SQLAlchemy scaffold. (It also configures the Mako template system, because I prefer Mako.)

I am also using PostgreSQL for my database. PostgreSQL supports nested transactions. This means I can setup the tables at the beginning of the test session, then start a transaction before each test happens and roll it back after the test; in turn, this means my tests operate in the same environment I expect to use in production, but they are also fast.

I based my approach on [sontek's blog post](http://sontek.net/blog/

Application specific host grouping in Riemann-dash

It is generally desirable to group all the hosts for a specific service into a single dashboard view. For example, all the web servers are in single view while all the database servers are in another view.

This is usually not an issue when you are sending custom metrics using Riemann client. However, there are cases where you are using something that you do not control how the metrics are being sent. i.e., Riemann-tools.

Since Riemann-tools scripts are application agnostic, in order for the dashboard view to group hosts, we must inject some application specific information into the tags field. Tags is a collection of arbitrary strings. In the case of Riemann-tools scripts you can pass in arbitrary strings on the command line.

riemann-health --host 127.0.0.1 --tag "prod" --tag "webserver"

A "virtualenv activate" for Anaconda environments

I've been using the Anaconda python package from continuum.io recently and found it to be a good way to get all the complex compiled libs you need for a scientific python environment. Even better, their conda tool lets you create environments much like virtualenv, but without having to re-compile stuff like numpy, which gets old very very quickly with virtualenv and can be a nightmare to get correctly set up on OSX.

The only thing missing was an easy way to switch environments - their docs suggest running python executables from the install folder, which I find a bit of a pain. Coincidentally I came across this article - Virtualenv's bin/activate is Doing It Wrong - which desribes a simple way to launch a sub-shell with certain environment variables set. Now simple was the key word for me since my bash-fu isn't very strong, but I managed to come up with the script below. Put this in a text file called conda-work

s3redirect

Authentication

Your AWS credentials can be set in a number of ways:

In a ".boto" file in your home folder. See Boto's documentation for how to create this file.
In the environment variables "AWS_ACCESS_KEY_ID" and "AWS_SECRET_ACCESS_KEY".
Passed in as arguments. -a or --access-key for the Access Key ID and -s or --access-secret for the Secret Access Key.

	Here is a list of scopes to use in Sublime Text 2 snippets -

	ActionScript: source.actionscript.2
	AppleScript: source.applescript
	ASP: source.asp
	Batch FIle: source.dosbatch
	C#: source.cs
	C++: source.c++
	Clojure: source.clojure
	CoffeeScript: source.coffee

	#!/usr/bin/env python

	# Compare a file on S3 to see if we have the latest version
	# If not, upload it and invalidate CloudFront

	import fnmatch
	import os
	import boto
	import pprint
	import re

	#!/bin/bash

	# Functions ==============================================

	# return 1 if global command line program installed, else 0
	# example
	# echo "node: $(program_is_installed node)"
	function program_is_installed {
	# set to 1 initially
	local return_=1

	\documentclass[a4paper]{article}

	% Cyrillic support
	\usepackage[T2A]{fontenc}
	\usepackage[utf8]{inputenc}
	\usepackage[english,russian]{babel}
	\DeclareSymbolFont{T2Aletters}{T2A}{cmr}{m}{it}

	% PDF search & cut'n'paste
	\usepackage{cmap}

	# Command Line to run from terminal
	# Logs result to file s3_backup.log
	# Command will run in the background
	s3cmd sync -v /path/to/folder/ s3://s3-bucket/folder/ > s3_backup.log 2>&1 &

	# Crontab command to sync folder to S3
	# Command will run 1am every day and logs result to /root/s3_backup.log
	0 1 * * * /usr/bin/s3cmd sync -rv /path/to/folder/ s3://s3-bucket/folder/ >> /root/s3_backup.log

	/Transparent pattern placed over an image, like we see on the bootstrap homepage: http://twitter.github.com/bootstrap/index.html/

	div {
	width: 200px;
	height: 200px;
	display: block;
	position: relative;
	background: url(images/background-image.png);
	}