Scripting Essentials for DevOps

Explore how to work with Bash variables, including assigning values without spaces and referencing them with $var. Learn how export promotes variables to the environment and how subshells affect scope.

Learn how bash distinguishes built-in from external commands and runs scripts with a shebang. Understand path, startup files like bash_profile and bashrc, and using source or dot to share variables.

Learn how to use bash aliases and decide whether to place them in bash profile or bashrc, and implement a bash_logout script to log last usage time on exit.

Learn how to use command substitution and quoting in bash, toggle foreground and background processes with ampersands, job controls, and no hangup to manage long-running tasks.

Learn how exit status signals command success or failure in bash, using zero versus non-zero values and the test command to drive if conditions and script flow.

Master how to redirect standard output and standard input in bash, using redirection operators like >, >>, <, here docs, and here strings, for efficient scripting.

Master bash file descriptors and redirection, directing stdout and stderr to files or /dev/null, and using device files for network access with netcat as a telnet alternative.

Explore bash functions, their scope and how they differ from scripts, then build practical loops such as for and while with read, aliasing, and grep examples.

Learn how to install Python 3 across Linux, Windows, and macOS using package managers and repositories, then run scripts and explore basics like variables, strings, and the print function.

Explore how Python lists function as arrays, using zero-based indexing and negative indices to access items. Learn to modify lists with append, insert, pop, and remove on dynamic data.

Explore Python basics for DevOps, including sorting lists with sort and sorted, iterating with for loops and range, and slicing lists to access indices.

Enforce digits in usernames with a range-based loop. Replace with a Python list comprehension and learn that strings are lists of characters, with join building the final string.

Master Python if conditions by evaluating boolean expressions with equality and membership, including in and not in, illustrated through authentication and string search in lists.

Explore how dictionaries store data as key-value pairs, enabling retrieval of a user's name, age, job, and country, and how lists of dictionaries support multi-user data and iteration by keys.

Modify items in a dictionary, add and remove keys, and loop through dictionaries and nested structures to manage user data, passwords, and language preferences in Python.

Explore how Python functions group code into reusable definitions, accept parameters, and return values; use positional and keyword calls, and apply them to authenticate users.

Learn how to organize Python functions into reusable modules, import them across files, and use selective or wildcard imports with aliases to manage authentication and user creation.

Install ruby via your package manager or compile from source, verify the version, and run scripts with puts or print, noting optional parentheses and interpreter location.

Explore Ruby string interpolation and quoting rules, comparing with Python and Bash, using print and printf style formats, escaping, and percent formatting to compose dynamic messages.

Explore how Ruby arrays work, from defining and looping with each to using while loops, ranges, and do...end blocks or braces for readable, compact code.

Explore how Ruby hashes mirror Python dictionaries, using keys as strings or symbols. Learn to access, nest, and iterate keys, values, and arrays.

Learn how Ruby uses functions and code blocks to inject external code via yield, with def syntax and do-end or curly brace blocks, for dynamic greetings and messages.

Explore Ruby modules, require, and namespace practices to organize code. Learn to require files, avoid name collisions, and work with hashes parsed from JSON.