create-ec2.sh

#!/bin/bash
# this is called shibang

#if handle the errors then it shows beautifully
set -euo pipefail

check_awscli(){
  if ! command -v aws &> /dev/null; then
	echo "AWS CLI is not installed. Please install it first." >&2
        return 1
  fi

}

install_awscli(){
  echo "Installing AWS CLI v2 on Linux..."

  # Download and install AWS CLI v2
  curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"
  sudo apt-get install -y unzip &> /dev/null
  unzip -q awscliv2.zip
  sudo ./aws/install

  # Verify installation
  aws --version

  # Clean up
  rm -rf awscliv2.zip ./aws


}

wait_for_instance() {
  local instance_id="$1"
  echo "Waiting for instance $instance_id to be in running state..."

  while true; do
    state=$(aws ec2 describe-instances --instance-ids "$instance_id" --query 'Reservations[0].Instances[0].State.Name' --output text)

    if [[ "$state" == "running" ]]; then  # Fixed spacing and condition syntax
      echo "Instance $instance_id is now running."
      break
    fi  # Fixed incorrect "if" closing

    sleep 10  # Moved outside the if condition to avoid logic errors
  done
}


create_ec2_instance(){
   local ami_id="$1"
   local instance_type="$2"
   local key_name="$3"
   local subnet_id="$4"
   local security_group_ids="$5"
   local instance_name="$6"
   
   # Run AWS CLI command to create EC2 instance
   instance_id=$(aws ec2 run-instances \
       --image-id "$ami_id" \
       --instance-type "$instance_type" \
       --key-name "$key_name" \
       --subnet-id "$subnet_id" \
       --security-group-ids "$security_group_ids" \
       --tag-specifications "ResourceType=instance, Tags=[{Key=Name, Value=$instance_name}]" \
       --query 'Instances[0].InstanceId' \
       --output text
   )
   
  if [[ -z "$instance_id" ]]; then
    echo "Failed to create EC2 instance." >&2
    exit 1
  
  if

   echo "Instance $instance_id created successfully."

   #Wait for the instance to be in running state
   wait_for_instance "instance_id"   
}

main(){
   
	if ! check_awscli; then
	cd install_awscli || exit 1
	  fi


   echo "Creating EC2 instance..."

   # Specify the parameters for creating the EC2 instance
   AMT_ID=""
   INSTANCE_TYPE="t2.micro"
   KEY_NAME=""
   SUBNET_ID=""
   SECCURITY_GROUP_IDS="" # Add your security group IDs separated by space
   INSTANCE_NAME="Shell-Script-EC2-Demo"

   #Call the function to create the EC2 instance
   create_ec2_instance "$AMT_ID" "$INSTANCE_TYPE" "$KEY_NAME" "$SUBNET_ID" "$SECURITY_GROUP_IDS" "$INSTANCE_NAME"

   echo "EC2 instance creation completed."


}

main "@"