theshank the-shank

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

-E: will describe the underlaying queries of the \ commands (cool for learning!)
-l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

Working with ansible-vault

I've been using a lot of Ansible lately and while almost everything has been great, finding a clean way to implement ansible-vault wasn't immediately apparent.

What I decided on was the following: put your secret information into a vars file, reference that vars file from your task, and encrypt the whole vars file using ansible-vault encrypt.

Let's use an example: You're writing an Ansible role and want to encrypt the spoiler for the movie Aliens.

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

Channels Are Not Enough

... or Why Pipelining Is Not That Easy

Golang Concurrency Patterns for brave and smart.

By @kachayev

Intro

PLEASE DON'T USE THIS GUIDE

It's over 9 years old (as of 2024-02-18), there are many better guides! You might like https://rust-unofficial.github.io/too-many-lists/

% Let's build a binary tree!

Let's build a binary tree of strings in Rust. To recap, each node in a binary tree:

must have a value

	// 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,

	def get_count(q):
	count_q = q.statement.with_only_columns([func.count()]).order_by(None)
	count = q.session.execute(count_q).scalar()
	return count

	q = session.query(TestModel).filter(...).order_by(...)

	# Slow: SELECT COUNT(*) FROM (SELECT ... FROM TestModel WHERE ...) ...
	print q.count()

	from random import choice
	from scrapy import signals
	from scrapy.exceptions import NotConfigured


	class RotateUserAgentMiddleware(object):
	"""Rotate user-agent for each request."""
	def __init__(self, user_agents):
	self.enabled = False
	self.user_agents = user_agents

	/**
	* Retrieves all the rows in the active spreadsheet that contain data and logs the
	* values for each row.
	* For more information on using the Spreadsheet API, see
	* https://developers.google.com/apps-script/service_spreadsheet
	*/
	function readRows() {
	var sheet = SpreadsheetApp.getActiveSheet();
	var rows = sheet.getDataRange();
	var numRows = rows.getNumRows();

	# to generate your dhparam.pem file, run in the terminal
	openssl dhparam -out /etc/nginx/ssl/dhparam.pem 2048