Roman Kubica

Blog

  • Powershell

    Run with Powershell
powershell.exe -command "& 'D:\powershell.ps1'" -ExecutionPolicy Bypass

    How long script takes?

    [datetime]$startDate = Get-Date
    [datetime]$endDate = Get-Date
    Write-Host $(NEW-TIMESPAN –Start $startDate –End $endDate )

    Find duplicate user values

    Get-ADUser -Filter { employeeID -like “*” } -SearchBase “OU=yourOU,DC=domain,DC=com” -property employeeID | Group-Object employeeID | Where-Object {$_.Count -ge 2} | select -ExpandProperty group | Select-Object Name, UserPrincipalName, SamAccountName, employeeID

  • Python

    Installation

    sudo apt install python3.10
sudo apt install python3-pip
pip install --user pipenv
python -m site --user-base
export PATH="$PATH:/pathAbove"
pipenv install
pipenv install flask

    Data structures

    Tuple

    Cannot edit after it is created – Immutable.

    thistuple = (“1”, “2”, “3”)
    for x in thistuple:
      print(x)

    List

    thislist = [“1”, “2”, “3”]
    for x in thislist:
      print(x)

  • Databases

    Postgres

    sudo apt install postgresql
    sudo service postgresql status
    sudo passwd postgres
    sudo -u postgres psql

    create database dbname;
create user username with encrypted password 'password';
grant all privileges on database dbname to username;

    Useful commands

    ALTER TABLE table ADD column dataType NOT NULL;

    \l list databases
    \c select database
    \dt list tables

  • Move a wordpress site to the new server

    Backup

    mysqldump -u root -p database1 > database.sql

    tar -zcvf data.tar.gz data

    Restore

    CREATE DATABASE database1;
    CREATE USER ‘user’@’localhost’ IDENTIFIED BY ‘pwd’;
    GRANT ALL PRIVILEGES ON database1 . * TO ‘user’@’localhost’;
    FLUSH PRIVILEGES;

    mysql -u root -p database1 < database.sql

    tar -zxvf data.tar.gz
    new website: 

    curl https://wordpress.org/latest.tar.gz | sudo -u www-data tar zx -C /srv/www

    update wp-config.php with the new password

    sudo chown -R www-data:www-data /var/www/data
    find /var/www/data -type d -exec chmod 755 {} \;
    find /var/www/data -type f -exec chmod 644 {} \;

    Server setup

    Reverse nginx proxy settings

    HTTP Apache2 settings

  • Ubuntu basic commands

    Update packages/apps

    sudo apt update && sudo apt upgrade

    Compress/Decompress a file

    tar -zcvf compressedFileName.tar.gz directoryName

    tar -zxvf compressedFileName.tar.gz

    WSL use ssh key on remote server:
    eval ‘ssh-agent -s‘
    ssh-add -t 60m ~/.ssh/id_rsa
    ssh -A user:address

    MySQL

    sudo apt install mysql-server
sudo mysql_secure_installation
sudo /etc/init.d/mysql start
sudo service mysql restart

    For WSL automatic start after restart: 

    sudo update-rc.d mysql defaults

    SSH

    adduser roman
usermod -aG sudo roman
su - hideo
mkdir ~/.ssh && chmod 700 ~/.ssh
touch ~/.ssh/authorized_keys && chmod 600 ~/.ssh/authorized_keys
nano ~/.ssh/authorized_keys
sudo ufw app list
sudo ufw allow OpenSSH
sudo ufw enable
sudo ufw status
sudo apt update
sudo apt upgrade -u
sudo reboot

    nginX

    sudo nano /etc/nginx/nginx.conf
uncomment server_tokens off;

  • Win10 tools and settings for work with Ubuntu

    I spent a last few years working in Ubuntu and Linux Mint. Now I have a new computer and will do the setup with Win10 and WSL2.

    WSL settings and setup

    Turn Windows features on or off:

    • Telnet client
    • Virtual Machine Platform
    • Windows subsystem for linux

    Powershell: 

    wsl --set-default-version 2

    Tools and apps

    • Ubuntu – install from windows appstore
    • Windows terminal – install from windows appstore
    • Docker desktop – needed for running docker in linux subsystem
    • Dbeaver.io – for accessing databases
    • Visual Studio Code

    Ubuntu settings

    ssh key

    windows terminal -> settings -> starting directory /mnt/d/

    Trouble with accessing D: drive as a regular user
    create or edit file /etc/wsl.conf and change default username to yours:

    [user]
    default=roman

  • Git: Basic commands and scenarios

    If you use a repository on one of the version control platforms like github, gitlab or bitbucket then you need some basic commands.

    When I was first introduced to git many years ago, I had to start with git pull, add, commit and push. I use this bulk of commands till nowdays. These commands basically update your local version Additionally you will need git status to see where you are and what you want to add to the repository.

    Commands

    git pull – gets you the new code from the repository
    git add yourFile.php – add data for next commit
    git commit -m “message about your changes” – you can put custom message to your commit changes
    git push – upload commits to the repository

    Scenarios

    Join the existing project

    When you are invited to the existing project/repository you need to get the code to your local machine. You can find the the URL in the web gui of the repository and then you command git clone git@github.com:bcvsolutions/CzechIdMng.git <optional my folder name>

    Creating your own project

    Start with creating Git repository online first and use git clone to get it locally. Otherwise you have to make adjustments to connect it later. You will have to deal with existing files or master branch.

    Easy workaround

    If you already have the code and want to push it to a new repository. Then in my opinion the easiest way to make it happen is through new folder and copy the files and folders there. Rename your current folder to _old if needed, then do a git clone. Copy the files and folders from your _old folder to the repository and proceed with add, commit and push. In this way you don’t have to deal with main branch or other commands.

    Git init way

    If you have a newer version of git 2.28+ then you can use. New default branch name is “main” on github.

    git config --global init.defaultBranch main

    git init
    git add .
    git commit -m “message”
    git remote add origin <URL of your git repository>
    git push -u origin main – here could be master instead of main, if you happen to have it as a new default branch.

    Create a develop branch

    As soon as you start testing your code locally or on the server. Try to create a new branch called develop or staging as it will help you in the future to divide production and test environment.

    git checkout main – go to the branch main
    git pull
    git checkout -b develop – create and switch to branch develop from current branch(main) – this is is a shortcut instead of using git branch

    When you have properly tested your code and you ready to push the changes to a production environment. Merge develop to main branch. That way you will have a working code in the production and space for developing new features.

    git checkout main
    git pull
    git merge develop

    Remove changes from a file

    This restores completely the file — you will loose changes in staged area
    git checkout HEAD — myfile.java

    Forgot to commit a change, which will cause a new commit with minor detail

    git reset –soft HEAD~1
    git commit -m “changes together”