Scripting with variables and loops in Azure - Mini Project: Build & Apply

Scripting with variables and loops

📖 Scenario: You are managing a small Azure environment. You want to automate the creation of multiple storage accounts with similar settings using a script. This will save time and reduce manual errors.

🎯 Goal: Create an Azure CLI script that uses variables and a loop to create three storage accounts with specific names and locations.

📋 What You'll Learn

Use a variable to store the base name for storage accounts

Use a variable to store the location for all storage accounts

Use a loop to create three storage accounts with names based on the base name and an index

Use the Azure CLI az storage account create command with the correct parameters

💡 Why This Matters

🌍 Real World

Automating repetitive cloud resource creation saves time and reduces mistakes in managing Azure environments.

💼 Career

Cloud engineers and DevOps professionals often write scripts like this to deploy and manage resources efficiently.

1

Set up base variables

Create two variables: baseName set to mystorage and location set to eastus.

Azure

# Your code here

Hint

Use simple variable assignment in bash style: variable=value.

2

Add a loop counter

Create a variable called count and set it to 3 to represent how many storage accounts to create.

Azure

baseName=mystorage
location=eastus
# Your code here

Hint

Use the same variable assignment style as before.

3

Write the loop to create storage accounts

Write a for loop using i from 1 to $count. Inside the loop, use az storage account create with --name set to ${baseName}${i} and --location set to $location. Use --resource-group myResourceGroup and --sku Standard_LRS as fixed parameters.

Azure

baseName=mystorage
location=eastus
count=3
# Your code here

Hint

Use $(seq 1 $count) to generate numbers from 1 to count.

4

Add a final echo statement

Add a line after the loop that echoes "Storage accounts created successfully." to confirm completion.

Azure

baseName=mystorage
location=eastus
count=3
for i in $(seq 1 $count)
do
  az storage account create --name ${baseName}${i} --resource-group myResourceGroup --location $location --sku Standard_LRS
 done
# Your code here

Hint

Use the echo command to print the message.

Practice

1. What is the main purpose of using variables in Azure scripting?

easy

A. To store values that can be reused throughout the script

B. To create loops that repeat commands

C. To delete resources automatically

D. To connect to the internet

Solution

1. Step 1: Understand what variables do

   Variables hold information like names or numbers that you want to use again without typing them multiple times.

2. Step 2: Identify the correct purpose in scripting

   Variables help scripts remember values so you can use them repeatedly and easily change them if needed.

3. Final Answer:

   To store values that can be reused throughout the script -> Option A

4. Quick Check:

   Variables = reusable values [OK]

Hint: Variables hold values to reuse in scripts [OK]

Common Mistakes:

• Confusing variables with loops
• Thinking variables delete resources
• Believing variables connect to internet

2. Which of the following is the correct way to declare a variable named count with value 5 in an Azure CLI script?

easy

A. var count = 5

B. let count = 5

C. set count=5

D. count=5

Solution

1. Step 1: Recall Azure CLI variable syntax

   In Azure CLI scripts (bash style), variables are assigned without keywords using name=value format.

2. Step 2: Match the correct syntax

   count=5 uses count=5, which is the correct bash style assignment.

3. Final Answer:

   count=5 -> Option D

4. Quick Check:

   Azure CLI variable = name=value [OK]

Hint: Use name=value to assign variables in Azure CLI [OK]

Common Mistakes:

• Using 'var' or 'let' which are not bash syntax
• Using 'set' which is Windows CMD syntax
• Adding spaces around '=' which breaks assignment

3. What will be the output of this Azure CLI script snippet?

for i in 1 2 3; do
  echo $((i * 2))
done

medium

A. 2 4 6

B. 0 1 2

C. 1 2 3

D. Syntax error

Solution

1. Step 1: Understand the loop iterations

   The loop runs with i values 1, then 2, then 3.

2. Step 2: Calculate the expression inside echo

   Each iteration prints i multiplied by 2: 1*2=2, 2*2=4, 3*2=6.

3. Final Answer:

   2 4 6 -> Option A

4. Quick Check:

   Loop * 2 = 2 4 6 [OK]

Hint: Multiply loop variable inside $(( )) for math [OK]

Common Mistakes:

• Confusing echo $i with echo $((i * 2))
• Expecting space-separated output on one line
• Thinking syntax error due to missing semicolons

4. Identify the error in this Azure CLI script snippet:

for i in 1 2 3 do
  echo $i
done

medium

A. echo command is incorrect

B. Variable $i is not defined

C. Missing semicolon or newline after for statement

D. done keyword is missing

Solution

1. Step 1: Check for correct for loop syntax

   In bash scripts, the for loop header must end with a semicolon or a newline before the do keyword.

2. Step 2: Identify the missing semicolon or newline

   The snippet has no semicolon or newline after for i in 1 2 3, causing syntax error.

3. Final Answer:

   Missing semicolon or newline after for statement -> Option C

4. Quick Check:

   For loop header needs semicolon/newline before do [OK]

Hint: Add semicolon or newline before do in for loops [OK]

Common Mistakes:

• Forgetting semicolon after for statement
• Assuming $i is undefined
• Thinking echo syntax is wrong

5. You want to create 3 Azure resource groups named rg1, rg2, and rg3 using a script with a loop and a variable prefix rg. Which script snippet correctly achieves this?

hard

A. prefix=rg
for i in 1 2 3; do
az group create --name $prefix + $i --location eastus
done

B. prefix=rg
for i in 1 2 3; do
az group create --name "$prefix$i" --location eastus
done

C. prefix=rg
for i in 1 2 3; do
az group create --name prefix$i --location eastus
done

D. for i in 1 2 3; do
az group create --name "rg" + i --location eastus
done

Solution

1. Step 1: Understand variable concatenation in bash

   To combine a variable and a number, use double quotes and place variables side by side like "$prefix$i".

2. Step 2: Check each option for correct syntax

   prefix=rg for i in 1 2 3; do az group create --name "$prefix$i" --location eastus done correctly uses "$prefix$i" to form names rg1, rg2, rg3. Others use invalid concatenation or miss quotes.

3. Final Answer:

   prefix=rg for i in 1 2 3; do az group create --name "$prefix$i" --location eastus done -> Option B

4. Quick Check:

   Use "$prefix$i" to join strings in bash [OK]

Hint: Use "$prefix$i" to join variable and number in bash [OK]

Common Mistakes:

• Using + for string concat in bash
• Not quoting variable expansions
• Writing variable names without $ sign