Alireza Amouzadeh Alireza2n

Clear Systemd Journal Logs in Ubuntu 20.04

Systemd has its own logging system called the journal, and the log files are stored in /var/log/journal.

Check current disk usage of journal files

sudo journalctl --disk-usage

Rotate journal files

Active journal files will be marked as archived, so that they are never written to in future.

🗺🐘 1000+ PostgreSQL EXTENSIONs

This is a list of URLs to PostgreSQL EXTENSION repos, listed in alphabetical order of parent repo, with active forks listed under each parent.

⭐️ >= 10 stars
⭐️⭐️ >= 100 stars
⭐️⭐️⭐️ >= 1000 stars
Numbers of stars might not be up-to-date.

Enable TCP port 2375 for external connection to Docker

See this issue.
Docker best practise to Control and configure Docker with systemd.

Create daemon.json file in /etc/docker:

 {"hosts": ["tcp://0.0.0.0:2375", "unix:///var/run/docker.sock"]}

Enable Docker Remote API with TLS client verification

Docker's Remote API can be secured via TLS and client certificate verification.
First of all you need a few certificates and keys:

CA certificate
Server certificate
Server key
Client certificate
Client key

Create certificate files

VMDK to VHDX

Follow [steps][1]:

Download: http://download.microsoft.com/download/9/1/E/91E9F42C-3F1F-4AD9-92B7-8DD65DA3B0C2/mvmc_setup.msi (thanks @xavery)
Open Powershell as administrator and run Import-Module 'C:\Program Files\Microsoft Virtual Machine Converter\MvmcCmdlet.psd1'
And after ConvertTo-MvmcVirtualHardDisk -SourceLiteralPath d:\scratch\vmx\VM-disk1.vmdk -VhdType DynamicHardDisk -VhdFormat vhdx -destination c:\vm-disk1

Django: Getting a Model from a string of the Model's name

Reference: http://stackoverflow.com/questions/4881607/django-get-model-from-string/26126935#26126935

model_name = 'Invoice'
app_name = 'invoice'
from django.apps import apps
Invoice = apps.get_model(app_label=app_name, model_name=model_name)
i = Invoice.objects.filter(id=1234).first()

	// 3D Dom viewer, copy-paste this into your console to visualise the DOM as a stack of solid blocks.
	// You can also minify and save it as a bookmarklet (https://www.freecodecamp.org/news/what-are-bookmarklets/)
	(() => {
	const SHOW_SIDES = false; // color sides of DOM nodes?
	const COLOR_SURFACE = true; // color tops of DOM nodes?
	const COLOR_RANDOM = false; // randomise color?
	const COLOR_HUE = 190; // hue in HSL (https://hslpicker.com)
	const MAX_ROTATION = 180; // set to 360 to rotate all the way round
	const THICKNESS = 20; // thickness of layers
	const DISTANCE = 10000; // ¯\\_(ツ)_/¯

	"""
	Django ORM Optimization Tips

	Caveats:
	* Only use optimizations that obfuscate the code if you need to.
	* Not all of these tips are hard and fast rules.
	* Use your judgement to determine what improvements are appropriate for your code.
	"""

	# ---------------------------------------------------------------------------

	:local queueName "Client-$leaseActMAC";

	:local ipAdd "$leaseActIP/32";

	:if ([:len [/queue simple find name=$queueName]] = 0) do={
	:log info "No Queue";
	/queue simple add name=$queueName target=($ipAdd) limit-at=10M/4M max-limit=10M/4M comment=[/ip dhcp-server lease get [find where active-mac-address=$leaseActMAC && active-address=$leaseActIP] host-name];
	} else={
	:log info "exists";
	:local ada [/queue simple get [find name=$queueName] target];

	from django.apps import AppConfig

	class ForumConfig(AppConfig):
	name = 'forum'
	# This function is the only new thing in this file
	# it just imports the signal file when the app is ready
	def ready(self):
	import your_app_name.signals