dhbradshaw

Check that your system supports systemd

pidof systemd
2733

If this return a number then your system supports systemd. Most Linux distributions in 2017 support systemd.

Check out the processes currently running.

Since systemd starts the process then all processes will be children of systemd

dhbradshaw

To change a field name in django 1.7+

1.  Edit the field name in the model (but remember the old field name: you need it for step 3!)
2.  Create an empty migration
$ python manage.py makemigrations --empty myApp
3.  Edit the empty migration (it's in the migrations folder in your app folder, and will be the most recent migration) by adding

migrations.RenameField('MyModel', 'old_field_name', 'new_field_name'),

to the operations list.

dhbradshaw

Boiled Eggs

• Place eggs into bottom of sauce pan.
• Cover eggs with water.
• Bring to boil.
• Allow to boil for 4 minutes.
• Turn off burner and allow to cool.
• Eat at will.

dhbradshaw

Postgres on WSL (Windows Subsystem for Linux) ubuntu 18.04

Hint: it's not different than running it under ubuntu without Windows.

Add postgres package registry

sudo apt install postgresql-common
sudo sh /usr/share/postgresql-common/pgdg/apt.postgresql.org.sh

Update apt

dhbradshaw

# Delete all redundant git branches

# 1. `git branch` lists all the branches
# 2. `xargs -L1` consumes the pipe output one line at a time, feeding it as an an arg to the target command
# 3. `git branch -d` deletes the branches that are redundant (already merged).
# Note: this print results for each branch, either 
# saying it's deleted or that you need to use -D to delete it because it's not redundant.

git branch | xargs -L1 git branch -d

dhbradshaw

Validate Excel .xlsx file xml using linux

Unzip

A .xlsx file is roughly a zipped bundle of xml files. To unzip them, just use unzip.

Here we send the unzipped contents of myfile.xlsx to the myfile_unzipped directory, which will be created on the fly.

unzip myfile.xlsx -d myfile_unzipped

dhbradshaw

export PATH="$PATH:/Users/doug/projects/flutter/bin" # Point to your downloaded flutter executable
# export CHROME_EXECUTABLE=/Applications/Brave\ Browser.app/Contents/MacOS/Brave\ Browser # Point to your chromium executable

dhbradshaw

# place this snippet into init.coffee in ~/.atom directory

atom.workspace.observeTextEditors (editor) ->
    if editor.getTitle() isnt "untitled"
        sp = editor.getPath().split('/')
        title = sp.slice(sp.length-2).join('/')
        editor.getTitle = -> title
        editor.getLongTitle = -> title

for item in atom.workspace.getPaneItems()

dhbradshaw

import boto3


s3 = boto3.resource('s3')
bucket = s3.Bucket('my-bucket-name')
bucket.object_versions.filter(Prefix='my/key/prefix').delete()

dhbradshaw

#!/bin/bash

DIR="/home/doug/Pictures/rotate_background"

# Get full path
FULL_PATH=$(gsettings get org.gnome.desktop.background picture-uri)

# Clean off quotes.
FULL_PATH=$(echo $FULL_PATH | sed 's/.$//' | sed 's/^.//')