SSH Postgres Installer

This script automates the installation and configuration of PostgreSQL on a remote server via SSH.

Usage

To use this script, execute the following command:

python install_postgres.py <host>

Replace with the hostname or IP address of the target server.

Requirements

Python 3.x
paramiko library (`pip install paramiko`)

Implementation Details

• The script provides two ways to connect to the provided host - via an SSH key, or via username/password if the former attempt is unsuccesfull.
• sudo support:
  • You cannot simply use sudo su - username in an exec_command before the command that needs root access, because each call to exec_command runs in its own subshell, as such the changes will not propagate back to the main session.
  • I tried to overcome this issue by writing a simple function-wrapper around exec_command, which (along side proper exceptions handling) checks if the command requires sudo perms, and if it does, handles admin password input if needed.
• Script is designed to work on Debian-based distros and on the latest postgresql version (usage of apt and the hardcoded path to the .conf file).
  • It is possible to adapt the solution to check both for an existing package manager by checking the distro first (debian/SuSE/redhat/gentoo/alpine/arch/..) in the folder /etc/os-release

Feedback from the company-interviewer:

В целом обратная связь по заданию
"Установка на Debian 12 не сработала из-за хардкода версии postgres в скрипте
 (в Debian 12 - postgres 15). После правки скрипта postgres установился, но не прошла проверка
 доступности из-за некорректной правки pg_hba.conf.

Плюсы:
* Хороший код
* Самая продуманная обработка ошибок Paramiko
* В readme описаны некоторые ограничения и мысли по реализации.
Минусы:
* Нет файла requirements.txt
* Программа не выдаёт статус выполнения инсталляции
* Программа ожидает лишних команд при запуске (это не соответствует исходному заданию)"

Author

Tkachenko Nikita
Moscow, Higher School of Economics: 3-rd year, Applied Mathematics, GPA: 7.3
My CV: link