commands.sh

#!/bin/bash

# Lab 09 - Job Registry with PostgreSQL
# Commands executed during the lab

# 1. Update system packages
sudo apt update

# 2. Install PostgreSQL
sudo apt install -y postgresql postgresql-contrib

# 3. Install Python and dependencies
sudo apt install -y python3 python3-pip python3-venv

# 3. Install Python and dependencies
python3 -m venv venv

# 3. Install Python and dependencies
source venv/bin/activate
pip install psycopg2-binary

# 4. Start PostgreSQL service
sudo systemctl start postgresql
sudo systemctl enable postgresql

# 5. Configure PostgreSQL access
sudo -u postgres psql -c "ALTER USER postgres PASSWORD 'labpassword';"

# 5. Configure PostgreSQL access
sudo -u postgres psql -c "CREATE DATABASE job_registry;"

# Step 1: Create Database Schema
nano schema.sql

# Step 2: Apply Schema
sudo -u postgres psql -d job_registry -f schema.sql

# Step 3: Verify Schema Creation
sudo -u postgres psql -d job_registry -c "\d jobs"

# Step 1: Create Job Manager Class
nano job_manager.py

# Step 2: Create Test Script
nano test_job_registry.py

# Step 3: Implement and Test
chmod +x test_job_registry.py

# Step 3: Implement and Test
python3 test_job_registry.py

# Verify Job Creation and Status Updates
sudo -u postgres psql -d job_registry -c "SELECT job_id, job_name, status, created_at FROM jobs ORDER BY job_id;"

# Verify Timestamps
sudo -u postgres psql -d job_registry -c "SELECT job_id, job_name, started_at, completed_at, (completed_at - started_at) AS duration FROM jobs WHERE status IN ('completed', 'failed');"

# Verify Results Storage
sudo -u postgres psql -d job_registry -c "SELECT job_id, job_name, result_data FROM jobs WHERE status = 'completed';"

# Verify Error Handling
sudo -u postgres psql -d job_registry -c "SELECT job_id, job_name, error_message FROM jobs WHERE status = 'failed';"

# Connection refused error
sudo systemctl status postgresql

# Connection refused error
sudo systemctl restart postgresql

# Module not found (`psycopg2`)
pip3 install --user psycopg2-binary

# Permission denied on database
sudo -u postgres psql -d job_registry -c "GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA public TO postgres;"

# Check existing jobs
sudo -u postgres psql -d job_registry -c "SELECT COUNT(*) FROM jobs;"