Creating an Amazon RDS DB instance

#!/bin/bash

# Script to create an Amazon RDS DB instance
# This script follows the tutorial at https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_CreateDBInstance.html

# Set up logging
LOG_FILE="rds_creation_$(date +%Y%m%d_%H%M%S).log"
exec > >(tee -a "$LOG_FILE") 2>&1

echo "Starting RDS DB instance creation script - $(date)"
echo "All actions will be logged to $LOG_FILE"
echo "=============================================="

# Function to check for errors in command output
check_error() {
    local output=$1
    local cmd=$2
    
    if echo "$output" | grep -i "error" > /dev/null; then
        echo "ERROR: Command failed: $cmd"
        echo "$output"
        cleanup_on_error
        exit 1
    fi
}

# Function to clean up resources on error
cleanup_on_error() {
    echo "Error encountered. Attempting to clean up resources..."
    
    if [ -n "$DB_INSTANCE_ID" ]; then
        echo "Deleting DB instance $DB_INSTANCE_ID..."
        aws rds delete-db-instance --db-instance-identifier "$DB_INSTANCE_ID" --skip-final-snapshot
        echo "Waiting for DB instance to be deleted..."
        aws rds wait db-instance-deleted --db-instance-identifier "$DB_INSTANCE_ID"
    fi
    
    if [ -n "$DB_SUBNET_GROUP_NAME" ] && [ "$CREATED_SUBNET_GROUP" = "true" ]; then
        echo "Deleting DB subnet group $DB_SUBNET_GROUP_NAME..."
        aws rds delete-db-subnet-group --db-subnet-group-name "$DB_SUBNET_GROUP_NAME"
    fi
    
    if [ -n "$SECURITY_GROUP_ID" ] && [ "$CREATED_SECURITY_GROUP" = "true" ]; then
        echo "Deleting security group $SECURITY_GROUP_ID..."
        aws ec2 delete-security-group --group-id "$SECURITY_GROUP_ID"
    fi
    
    echo "Cleanup completed."
}

# Generate a random identifier for resources
RANDOM_ID=$(openssl rand -hex 4)
DB_INSTANCE_ID="mydb-${RANDOM_ID}"
DB_SUBNET_GROUP_NAME="mydbsubnet-${RANDOM_ID}"
SECURITY_GROUP_NAME="mydbsg-${RANDOM_ID}"

# Track created resources
CREATED_SECURITY_GROUP="false"
CREATED_SUBNET_GROUP="false"

# Array to store created resources for display
declare -a CREATED_RESOURCES

echo "Step 1: Checking for default VPC..."
VPC_OUTPUT=$(aws ec2 describe-vpcs --filters "Name=isDefault,Values=true")
check_error "$VPC_OUTPUT" "aws ec2 describe-vpcs"

# Extract VPC ID
VPC_ID=$(echo "$VPC_OUTPUT" | grep -o '"VpcId": "[^"]*' | cut -d'"' -f4)

if [ -z "$VPC_ID" ]; then
    echo "No default VPC found. Please create a VPC before running this script."
    exit 1
fi

echo "Using VPC: $VPC_ID"

echo "Step 2: Getting subnets from the VPC..."
SUBNET_OUTPUT=$(aws ec2 describe-subnets --filters "Name=vpc-id,Values=$VPC_ID")
check_error "$SUBNET_OUTPUT" "aws ec2 describe-subnets"

# Extract subnet IDs (we need at least 2 in different AZs)
SUBNET_IDS=($(echo "$SUBNET_OUTPUT" | grep -o '"SubnetId": "[^"]*' | cut -d'"' -f4))

if [ ${#SUBNET_IDS[@]} -lt 2 ]; then
    echo "Error: Need at least 2 subnets in different AZs. Found ${#SUBNET_IDS[@]} subnets."
    exit 1
fi

echo "Found ${#SUBNET_IDS[@]} subnets: ${SUBNET_IDS[*]}"

echo "Step 3: Creating security group for RDS..."
SG_OUTPUT=$(aws ec2 create-security-group \
    --group-name "$SECURITY_GROUP_NAME" \
    --description "Security group for RDS database access" \
    --vpc-id "$VPC_ID")
check_error "$SG_OUTPUT" "aws ec2 create-security-group"

SECURITY_GROUP_ID=$(echo "$SG_OUTPUT" | grep -o '"GroupId": "[^"]*' | cut -d'"' -f4)
CREATED_SECURITY_GROUP="true"
CREATED_RESOURCES+=("Security Group: $SECURITY_GROUP_ID ($SECURITY_GROUP_NAME)")

echo "Created security group: $SECURITY_GROUP_ID"

echo "Step 4: Adding inbound rule to security group..."
# Note: In a production environment, you should restrict this to specific IP ranges
# We're using the local machine's IP address for this example
MY_IP=$(curl -s https://checkip.amazonaws.com)
check_error "$MY_IP" "curl -s https://checkip.amazonaws.com"

INGRESS_OUTPUT=$(aws ec2 authorize-security-group-ingress \
    --group-id "$SECURITY_GROUP_ID" \
    --protocol tcp \
    --port 3306 \
    --cidr "${MY_IP}/32")
check_error "$INGRESS_OUTPUT" "aws ec2 authorize-security-group-ingress"

echo "Added inbound rule to allow MySQL connections from ${MY_IP}/32"

echo "Step 5: Creating DB subnet group..."
# Select the first two subnets for the DB subnet group
SUBNET1=${SUBNET_IDS[0]}
SUBNET2=${SUBNET_IDS[1]}

SUBNET_GROUP_OUTPUT=$(aws rds create-db-subnet-group \
    --db-subnet-group-name "$DB_SUBNET_GROUP_NAME" \
    --db-subnet-group-description "Subnet group for RDS tutorial" \
    --subnet-ids "$SUBNET1" "$SUBNET2")
check_error "$SUBNET_GROUP_OUTPUT" "aws rds create-db-subnet-group"

CREATED_SUBNET_GROUP="true"
CREATED_RESOURCES+=("DB Subnet Group: $DB_SUBNET_GROUP_NAME")

echo "Created DB subnet group: $DB_SUBNET_GROUP_NAME"

echo "Step 6: Creating a secure password in AWS Secrets Manager..."
SECRET_NAME="rds-db-credentials-${RANDOM_ID}"
SECRET_OUTPUT=$(aws secretsmanager create-secret \
    --name "$SECRET_NAME" \
    --description "RDS DB credentials for $DB_INSTANCE_ID" \
    --secret-string '{"username":"adminuser","password":"'"$(openssl rand -base64 16)"'"}')
check_error "$SECRET_OUTPUT" "aws secretsmanager create-secret"

SECRET_ARN=$(echo "$SECRET_OUTPUT" | grep -o '"ARN": "[^"]*' | cut -d'"' -f4)
CREATED_RESOURCES+=("Secret: $SECRET_ARN ($SECRET_NAME)")

echo "Created secret: $SECRET_NAME"

echo "Step 7: Retrieving the username and password from the secret..."
SECRET_VALUE_OUTPUT=$(aws secretsmanager get-secret-value --secret-id "$SECRET_NAME" --query 'SecretString' --output text)
check_error "$SECRET_VALUE_OUTPUT" "aws secretsmanager get-secret-value"

DB_USERNAME=$(echo "$SECRET_VALUE_OUTPUT" | grep -o '"username":"[^"]*' | cut -d'"' -f4)
DB_PASSWORD=$(echo "$SECRET_VALUE_OUTPUT" | grep -o '"password":"[^"]*' | cut -d'"' -f4)

echo "Retrieved database credentials"

echo "Step 8: Creating RDS DB instance..."
echo "This may take several minutes..."

DB_OUTPUT=$(aws rds create-db-instance \
    --db-instance-identifier "$DB_INSTANCE_ID" \
    --db-instance-class db.t3.micro \
    --engine mysql \
    --master-username "$DB_USERNAME" \
    --master-user-password "$DB_PASSWORD" \
    --allocated-storage 20 \
    --vpc-security-group-ids "$SECURITY_GROUP_ID" \
    --db-subnet-group-name "$DB_SUBNET_GROUP_NAME" \
    --backup-retention-period 7 \
    --no-publicly-accessible \
    --no-multi-az)
check_error "$DB_OUTPUT" "aws rds create-db-instance"

CREATED_RESOURCES+=("DB Instance: $DB_INSTANCE_ID")

echo "DB instance creation initiated: $DB_INSTANCE_ID"
echo "Waiting for DB instance to become available..."
echo "This may take 5-10 minutes..."

aws rds wait db-instance-available --db-instance-identifier "$DB_INSTANCE_ID"
DB_STATUS=$?

if [ $DB_STATUS -ne 0 ]; then
    echo "Error waiting for DB instance to become available"
    cleanup_on_error
    exit 1
fi

echo "DB instance is now available!"

echo "Step 9: Getting connection information..."
ENDPOINT_INFO=$(aws rds describe-db-instances \
    --db-instance-identifier "$DB_INSTANCE_ID" \
    --query 'DBInstances[0].[Endpoint.Address,Endpoint.Port,MasterUsername]' \
    --output text)
check_error "$ENDPOINT_INFO" "aws rds describe-db-instances"

DB_ENDPOINT=$(echo "$ENDPOINT_INFO" | awk '{print $1}')
DB_PORT=$(echo "$ENDPOINT_INFO" | awk '{print $2}')
DB_USER=$(echo "$ENDPOINT_INFO" | awk '{print $3}')

echo "=============================================="
echo "DB Instance successfully created!"
echo "=============================================="
echo "Connection Information:"
echo "  Endpoint: $DB_ENDPOINT"
echo "  Port: $DB_PORT"
echo "  Username: $DB_USER"
echo "  Password: [Stored in AWS Secrets Manager - $SECRET_NAME]"
echo ""
echo "To connect using the mysql client:"
echo "mysql -h $DB_ENDPOINT -P $DB_PORT -u $DB_USER -p"
echo "=============================================="

echo ""
echo "Resources created:"
for resource in "${CREATED_RESOURCES[@]}"; do
    echo "  - $resource"
done
echo ""

# Ask user if they want to clean up resources
echo ""
echo "==========================================="
echo "CLEANUP CONFIRMATION"
echo "==========================================="
echo "Do you want to clean up all created resources? (y/n): "
read -r CLEANUP_CHOICE

if [[ $CLEANUP_CHOICE =~ ^[Yy] ]]; then
    echo "Starting cleanup process..."
    
    echo "Step 1: Deleting DB instance $DB_INSTANCE_ID..."
    aws rds delete-db-instance --db-instance-identifier "$DB_INSTANCE_ID" --skip-final-snapshot
    echo "Waiting for DB instance to be deleted..."
    aws rds wait db-instance-deleted --db-instance-identifier "$DB_INSTANCE_ID"
    
    echo "Step 2: Deleting secret $SECRET_NAME..."
    aws secretsmanager delete-secret --secret-id "$SECRET_NAME" --force-delete-without-recovery
    
    echo "Step 3: Deleting DB subnet group $DB_SUBNET_GROUP_NAME..."
    aws rds delete-db-subnet-group --db-subnet-group-name "$DB_SUBNET_GROUP_NAME"
    
    echo "Step 4: Deleting security group $SECURITY_GROUP_ID..."
    aws ec2 delete-security-group --group-id "$SECURITY_GROUP_ID"
    
    echo "Cleanup completed successfully!"
else
    echo "Skipping cleanup. Resources will remain in your AWS account."
    echo "To clean up later, you'll need to delete these resources manually."
fi

echo "Script completed successfully!"