DevOps Script Command Explanations Reference Manual

The layout below illustrates how various script formats are compiled, parsed, and executed across client terminals, virtualization platforms, docker daemons, and remote cloud infrastructure.

SCRIPT 1: validate_workstation.sh

System Audit Engine (Setup Project 0)

#!/usr/bin/env bash

This line specifies that the kernel loader must execute the script using the bash shell interpreter, ensuring that standard Unix command interfaces are resolved correctly.

set -euo pipefail

This configuration terminates execution immediately if any command returns a non-zero exit status, flags references to undefined variables as errors, and propagates errors inside command pipelines.

ACTUAL_HOSTNAME=$(hostname)

This variable declaration runs the system hostname tool inside a subshell and records the stdout output, identifying the active host.

if mountpoint -q "/media/sf_devops_share"; then

This conditional loop inspects the system mount records silently to confirm that the VirtualBox host directory is mounted inside the Linux filesystem.

SCRIPT 2: bootstrap_linux.sh

Linux Workstation Auto-Provisioner (Project 1)

for dir in Projects Scripts Downloads Backups Logs; do

This loop iterates over a list of directory names to automate creating standard workspace folders in the user's home path.

mkdir -p "${HOME}/${dir}"

This command creates the target folder path, using the -p flag to build parent directories automatically and prevent errors if the directory already exists.

sudo apt-get install -y -qq curl wget git unzip zip net-tools tree htop

This command uses apt-get to install core tools silently (-qq) in non-interactive mode (-y), ensuring all required developer tools are installed.

if ! grep -Fq "alias ll='ls -laF'" ~/.bashrc; then echo "alias ll='ls -laF'" >> ~/.bashrc; fi

This conditional statement checks if the specified text string is already present inside `.bashrc` and appends the alias if it is missing, preventing duplicate profile listings.

SCRIPT 3: simulate_git_flow.sh

Git Branching & Conflict Simulation Engine (Project 2)

git init

This command creates a hidden `.git` tracking directory in your project folder, turning it into a local Git repository.

git checkout -b feature/login

This command creates a new feature branch and switches your workspace context to it, isolating your development work.

git merge feature/login || echo "Conflict triggered"

This command merges the feature branch into main. If a conflict occurs, the pipeline catches the error and outputs a notification instead of failing the script.

SCRIPT 4: docker-compose.yml

Multi-Container Orchestration Manifest (Project 4)

version: '3.8'

This key defines the Docker Compose file format version, mapping configuration attributes to the features supported by your Docker engine.

depends_on: - mongo-db

This setting configures startup order, instructing Docker Compose to launch database containers and wait for them to run before starting the application service.

volumes: - mongo-data:/data/db

This definition maps a persistent Docker volume to the database container's data directory, protecting your database files from loss when the container restarts.

SCRIPT 5: main.tf

Terraform Infrastructure-as-Code Declarations (Project 6)

provider "aws" { region = "us-east-1" }

This configuration initializes the AWS provider plug-in, setting target regional API endpoints to us-east-1.

ami = "ami-0c7217cdde317cfec"

This setting defines the Amazon Machine Image ID to provision (Ubuntu Server 22.04 LTS), configuring the root OS image for the new virtual server.

user_data = <<-EOF ... EOF

This setting defines a startup script (user data) for the EC2 instance, installing and starting the Nginx web server automatically when the virtual machine boots.

SCRIPT 6: Jenkinsfile

Continuous Integration Declarative Pipeline (Project 3 & 8)

agent any

This setting instructs the Jenkins controller to allocate any available worker node to execute the pipeline stages.

junit '**/target/surefire-reports/*.xml'

This step parses XML test report files generated by Maven to display test results and failure logs on the Jenkins dashboard.

archiveArtifacts artifacts: '**/target/*.jar', fingerprint: true

This step copies generated jar files from the build agent workspace to the Jenkins controller storage, archiving the build artifacts.