Understanding the power of Shell Scripting in DevOps
Shell scripting is like a magic wand for DevOps professionals.
It allows you to execute a series of commands effortlessly, automating tasks and streamlining workflows. Imagine having a script, say "my_file.sh," that runs multiple commands in one go. Here's a simple example:
#!/bin/bash
touch devops.txt
echo "I'm learning DevOps and on day04 of my 90DaysOfDevOps journey" > devops.txt
cat devops.txt
Running this script will create a file, write a message, and display it—all in one swift motion.
The Shebang Mystery: #!/bin/bash vs. #!/bin/sh
The shebang (#!) at the start of a script tells the system which shell to use. Use #!/bin/bash
for scripts that require advanced Bash features, like arrays. Opt for #!/bin/sh
for basic, more portable scripts. Choose wisely based on your script's needs!
Challenge Accepted: A Simple Shell Script
Create a script named "devOps_challenge.sh" with the following content:
#!/bin/bash
echo "I will complete #90DaysOfDevOps challenge"
Save and run it to see your commitment in action!
Interactive Scripting: User Input and Arguments
Here's how to create a script that takes user input and command-line arguments:
#!/bin/bash
read -p "Enter your name: " user_name
arg1=$1
arg2=$2
echo "User input: $user_name"
echo "Argument 1: $arg1"
echo "Argument 2: $arg2"
Decision Making: If-Else in Shell Scripting
Compare two numbers using an if-else statement:
#!/bin/bash
read -p "Enter the first number: " num1
read -p "Enter the second number: " num2
if [ $num1 -gt $num2 ]; then
echo "$num1 is greater than $num2"
elif [ $num1 -lt $num2 ]; then
echo "$num1 is less than $num2"
else
echo "$num1 is equal to $num2"
fi
Shell scripting is a powerful tool in the DevOps toolkit, enabling automation and efficiency. Embrace it to enhance your DevOps journey!