Alpha AlphaWong

Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

How to install redis-cli and psql client on your machine with Docker

Preparing docker images

We will use minimalistic Linux distribution called Alpine (5MB)

Dockerfile of redis-cli

FROM alpine:latest
RUN apk --update add redis

How to install redis-cli and psql client on your machine with Docker

Preparing docker images

We will use minimalistic Linux distribution called Alpine (5MB)

Dockerfile of redis-cli

FROM alpine:latest
RUN apk --update add redis

Go, multiple packages and coveralls.io

Single profile for single Go package

For Go projects that consist of only one package, the following Travis configuration is enough to get started with coveralls.io. You may want to encrypt your $COVERALLS_TOKEN via Travis encryption keys though.

language: go
go:
 - 1.3.1

	# Nerd Fonts for your IDE
	# https://www.nerdfonts.com/font-downloads

	brew tap homebrew/cask-fonts && brew install --cask font-3270-nerd-font
	brew tap homebrew/cask-fonts && brew install --cask font-fira-mono-nerd-font
	brew tap homebrew/cask-fonts && brew install --cask font-inconsolata-go-nerd-font
	brew tap homebrew/cask-fonts && brew install --cask font-inconsolata-lgc-nerd-font
	brew tap homebrew/cask-fonts && brew install --cask font-inconsolata-nerd-font
	brew tap homebrew/cask-fonts && brew install --cask font-monofur-nerd-font
	brew tap homebrew/cask-fonts && brew install --cask font-overpass-nerd-font

	1) Install cloudflared using homebrew:

	brew install cloudflare/cloudflare/cloudflared

	2) Create /usr/local/etc/cloudflared/config.yaml, with the following content

	proxy-dns: true
	proxy-dns-upstream:
	- https://1.1.1.1/dns-query
	- https://1.0.0.1/dns-query

	[unix_http_server]
	file=/tmp/supervisor.sock ; path to your socket file

	[supervisord]
	logfile=/var/log/supervisord/supervisord.log ; supervisord log file
	logfile_maxbytes=50MB ; maximum size of logfile before rotation
	logfile_backups=10 ; number of backed up logfiles
	loglevel=error ; info, debug, warn, trace
	pidfile=/var/run/supervisord.pid ; pidfile location
	nodaemon=false ; run supervisord as a daemon

	// haversin(θ) function
	func hsin(theta float64) float64 {
	return math.Pow(math.Sin(theta/2), 2)
	}

	// Distance function returns the distance (in meters) between two points of
	// a given longitude and latitude relatively accurately (using a spherical
	// approximation of the Earth) through the Haversin Distance Formula for
	// great arc distance on a sphere with accuracy for small distances
	//

	sudo apt install ruby ruby-dev
	sudo gem install travis
	# install path: /var/lib/gems/