Tharwat96

sed:

to substitute something with something else:

sed "s/something/something_else/g" file.sh

the g in the right is for changing all occurrences in all lines, if it was not written, only the first occurrence of each line is replaced

sed example to substitute new lines with spaces:
sed ':a;N;$!ba;s/\n/ /g' file

Tharwat96

# write/overwrite file

f = open("text.txt", "w")
f.write("bla bla")
f.close()

# search for something in file

with open('data') as f:
    if 'test' in f.read():

Tharwat96

Rails naming conventions

General Ruby conventions

Class names are CamelCase.

Methods and variables are snake_case.

Methods with a ? suffix will return a boolean.

Tharwat96

In this file I will list stubborn errors encountered and their fix in order not to fall for them again and solve them fast

SSH Build keeps failing because of secret key authorization error.

• Make sure to generate the keys using rsa encryption.
• Make sure that both keys (pub and priv) are a pair.
• Don't trust Jenkins connections check as it has some issues sometimes.
• Try using different Jenkins version on your development env to make sure it is not a jenkins error.

Tharwat96

[Unit]
Description=Gitea (Git with a cup of tea)
After=syslog.target
After=network.target
#After=mysqld.service
#After=postgresql.service
#After=memcached.service
#After=redis.service

[Service]

Tharwat96

# delete all pods that are evicted

kubectl get pods --all-namespaces | grep Evicted | awk '{print $2 " --namespace=" $1}' | xargs kubectl delete pod

# delete all pods that are erroring and sleep a bit to avoid rate limit
# you can add head or tail to work in batches

kubectl get pods --all-namespaces | grep 'Evicted\|Error\|ContainerStatusUnknown' | awk '{print $2 " --namespace=" $1}' | xargs -I % sh -c '{ kubectl delete pod  %; sleep 0.1; }'

# print all failing pods with their describe reason of failiure

Tharwat96

List the active account name

gcloud auth list

Set the compute zone

gcloud config set compute/zone us-central1-a

Creates a cluster called bootcamp with 5 nodes (including the master)

gcloud container clusters create bootcamp --num-nodes 5 --scopes "https://www.googleapis.com/auth/projecthosting,storage-rw"

Tharwat96

// any file to use the Eloquent driver

<?php
require "../vendor/autoload.php";
require "../config/database.php";
use Illuminate\Database\Capsule\Manager as Capsule;

$dbclass = new Database();
$capsule = new Capsule();
$capsule->addConnection($dbclass->EloquentConnection());

Tharwat96

Docker Cheat Sheet

Copy a file from host to container:

docker cp file.xz container_name:/tmp/file.xz

List all containers with their volumes

docker ps -a --format '{{ .ID }}' | xargs -I {} docker inspect -f '{{ .Name }}{{ printf "\n" }}{{ range .Mounts }}{{ printf "\n\t" }}{{ .Type }} {{ if eq .Type "bind" }}{{ .Source }}{{ end }}{{ .Name }} => {{ .Destination }}{{ end }}{{ printf "\n" }}' {}

Tharwat96

# This is a comment, we will use comments to explain.
# There are three types of data in YAML:
# - key value pair, lists/arrays, dictionaries

# key value pair:
Fruit: Apple
Vegetable: Carrot
Liquid: Water
Meat: Chicken