Diogo Souza da Silva diogok

Blog 2020/9/1

Quick-n-dirty QEMU script to spin up Debian on various CPU's

This script downloads one of the QEMU images from https://people.debian.org/~aurel32/qemu/ and boots up a vm.

Getting Started

Make sure Docker is installed!

Get your Minio endpoint url, accesskey, and secretkey ready!

Install Docker Plugin

docker plugin install rexray/s3fs \

Rationale

This snippet is a sample showing how to implement CloudWatch Logs streaming to ElasticSearch using terraform. I wrote this gist because I didn't found a clear, end-to-end example on how to achieve this task. In particular, I understood the resource "aws_lambda_permission" "cloudwatch_allow" part by reading a couple of bug reports plus this stackoverflow post.

The js file is actually the Lambda function automatically created by AWS when creating this pipeline through the web console. I only added a endpoint variable handling so it is configurable from terraform.

Running a docker registry with Minio S3 backend

Run minio in a container

docker run -d -p 9000:9000 --name minio minio/minio server /export

Use docker logs to retrieve access key and secret key from minio container

docker logs minio

Create config.yml for Docker Registry

This file will have to be mounted to /etc/docker/registry/config.yml

I have been an aggressive Kubernetes evangelist over the last few years. It has been the hammer with which I have approached almost all my deployments, and the one tool I have mentioned (shoved down clients throats) in almost all my foremost communications with clients, and it was my go to choice when I was mocking my first startup (saharacluster.com).

A few weeks ago Docker 1.13 was released and I was tasked with replicating a client's Kubernetes deployment on Swarm, more specifically testing running compose on Swarm.

And it was a dream!

All our apps were already dockerised and all I had to do was make a few modificatons to an existing compose file that I had used for testing before prior said deployment on Kubernetes.

And, with the ease with which I was able to expose our endpoints, manage volumes, handle networking, deploy and tear down the setup. I in all honesty see no reason to not use Swarm. No mission-critical feature, or incredibly convenient really nice to have feature in Kubernetes that I'm go

Wow. Stripped-down, reading-ready summary follows below, but here's the original link:

https://twitter.com/sarahmei/status/783340259073335296

The author, Sarah Mei (@sarahmei) has also registered liveablecode.com (no content yet).

[begin summary]

Conventions

A = [xA, yA] is a point on the 2D plane. Same for B, C, ...
lengths are in any unit (ex: pixels)
code snippets are in JavaScript

Degrees to radians

angleRad = angleDeg * Math.PI / 180;

Simple module that makes gears with circular-shaped teeth. The gears maintain their shape even for extremely low teeth numbers up to 2. Parameters:

teeth: number of teeth.
step: width of one teeth (diameter of the circle).

Two gears produced with the same step will transfer movement, so one typically fixes a step for all the gears and varies teeth for each gear, which decides the radius and transfer ratio. Example:

	(defn code-mirror
	"Create a code-mirror editor. The parameters:
	value-atom (reagent atom)
	when this changes, the editor will update to reflect it.
	options
	:style (reagent style map)
	will be applied to the container element
	:js-cm-opts
	options passed into the CodeMirror constructor
	:on-cm-init (fn [cm] -> nil)

	// Usage:
	// Copy and paste all of this into a debug console window of the "Who is Hiring?" comment thread
	// then use as follows:
	//
	// query(term \| [term, term, ...], term \| [term, term, ...], ...)
	//
	// When arguments are in an array then that means an "or" and when they are seperate that means "and"
	//
	// Term is of the format:
	// ((-)text/RegExp) ( '-' means negation )