Understanding Azure DevOps YAML

Oct 13, 2025 by wbrum.org 2 views

Introduction

In the world of Azure DevOps, pipelines are the backbone of continuous integration and continuous deployment (CI/CD) workflows. However, sometimes, you may need to run pipeline jobs in a loop, with a parameter that specifies the number of iterations. This can be particularly useful when you need to perform repetitive tasks, such as testing or deployment, multiple times. In this article, we will explore how to achieve this using Azure DevOps YAML.

Understanding Azure DevOps YAML

Azure DevOps YAML is a powerful tool that allows you to define your pipeline configuration using a YAML file. This file contains a set of instructions that Azure DevOps will execute during the pipeline run. YAML is a human-readable serialization format that is widely used in DevOps and other areas of software development.

Defining a Pipeline with a Loop

To define a pipeline with a loop, you will need to use the parameters section in your YAML file. This section allows you to define input parameters that can be used during the pipeline run. In this case, we will define a parameter called myarray that will specify the number of iterations.

trigger:
- master
parameters:

name: myarray
type: string
default: 5
values:

5
10
15
20
25

In this example, we have defined a parameter called myarray with a type of string. We have also specified a default value of 5 and a set of possible values that can be used during the pipeline run.

Using a Loop in Your Pipeline

Now that we have defined our parameter, we can use it to create a loop in our pipeline. We will use the for loop syntax to iterate over the values specified in the myarray parameter.

steps:
  - task: Bash@3
    displayName: 'Loop Example'
    inputs:
      command: 'echo'
      arguments: 'myarray is $(myarray)'
  - task: Bash@3
    displayName: 'Loop Example'
    inputs:
      command: 'for'
      arguments: 'i in $(myarray); do echo $i; done'

In this example, we have defined two tasks: one that simply echoes the value of the myarray parameter, and another that uses a for loop to iterate over the values specified in the myarray parameter.

Using a Loop with a Parameter

Now that we have defined our loop, we can use it with a parameter to specify the number of iterations. We will use the parameters section to define a parameter called myarray that will specify the number of iterations.

trigger:
- master
parameters:

name: myarray
type: string
default: 5
values:

5
10
15
20
25



steps:

task: Bash@3
displayName: 'Loop Example'
inputs:
command: 'for'
arguments: 'i in $(myarray); do echo $i; done'

In this example, we have defined a parameter called myarray that will specify the number of iterations. We have also defined a task that uses a for loop to iterate over the values specified in the myarray parameter.

Using a Loop with a Condition

Now that we have defined our loop, we can use it with a condition to specify when the loop should be executed. We will use the condition section to define a condition that will determine whether the loop should be executed.

trigger:
- master
parameters:

name: myarray
type: string
default: 5
values:

5
10
15
20
25



steps:

task: Bash@3
displayName: 'Loop Example'
inputs:
command: 'for'
arguments: 'i in $(myarray); do echo $i; done'
condition: and(succeeded(), eq(variables['myarray'], 5))

In this example, we have defined a condition that will determine whether the loop should be executed. The condition is and(succeeded(), eq(variables['myarray'], 5)), which means that the loop will only be executed if the previous task was successful and the value of the myarray parameter is 5.

Conclusion

In this article, we have explored how to use Azure DevOps YAML to define a pipeline with a loop. We have defined a parameter called myarray that will specify the number of iterations, and used it to create a loop in our pipeline. We have also used a condition to specify when the loop should be executed. With this knowledge, you can now create complex pipelines with loops and conditions to automate your CI/CD workflows.

Best Practices

When using Azure DevOps YAML to define a pipeline with a loop, here are some best practices to keep in mind:

Use meaningful names for your parameters and variables.
Use clear and concise syntax for your loops and conditions.
Use the condition section to specify when the loop should be executed.
Use the parameters section to define input parameters that can be used during the pipeline run.
Use the steps section to define the tasks that will be executed during the pipeline run.

Common Issues

When using Azure DevOps YAML to define a pipeline with a loop, here are some common issues to watch out for:

Make sure that the parameters section is defined correctly.
Make sure that the steps section is defined correctly.
Make sure that the condition section is defined correctly.
Make sure that the loop is executed correctly.
Make sure that the condition is evaluated correctly.

Troubleshooting

When using Azure DevOps YAML to define a pipeline with a loop, here are some troubleshooting tips to keep in mind:

Check the Azure DevOps logs for errors.
Check the pipeline run history for errors.
Check the pipeline configuration for errors.
Check the loop and condition syntax for errors.
Check the parameter and variable values for errors.

Conclusion

Q: What is Azure DevOps YAML?

A: Azure DevOps YAML is a powerful tool that allows you to define your pipeline configuration using a YAML file. This file contains a set of instructions that Azure DevOps will execute during the pipeline run.

Q: How do I define a pipeline with a loop in Azure DevOps YAML?

A: To define a pipeline with a loop in Azure DevOps YAML, you will need to use the parameters section to define input parameters that can be used during the pipeline run. You will also need to use the steps section to define the tasks that will be executed during the pipeline run.

Q: What is the difference between a loop and a condition in Azure DevOps YAML?

A: A loop is a set of instructions that will be executed repeatedly, while a condition is a set of instructions that will be executed only if a certain condition is met.

Q: How do I use a loop with a parameter in Azure DevOps YAML?

A: To use a loop with a parameter in Azure DevOps YAML, you will need to define a parameter in the parameters section and use it in the steps section to define the tasks that will be executed during the pipeline run.

Q: How do I use a condition with a loop in Azure DevOps YAML?

A: To use a condition with a loop in Azure DevOps YAML, you will need to define a condition in the condition section and use it to determine whether the loop should be executed.

Q: What are some common issues to watch out for when using Azure DevOps YAML to define a pipeline with a loop?

A: Some common issues to watch out for when using Azure DevOps YAML to define a pipeline with a loop include:

Make sure that the parameters section is defined correctly.
Make sure that the steps section is defined correctly.
Make sure that the condition section is defined correctly.
Make sure that the loop is executed correctly.
Make sure that the condition is evaluated correctly.

Q: How do I troubleshoot issues with Azure DevOps YAML loops?

A: To troubleshoot issues with Azure DevOps YAML loops, you can:

Check the Azure DevOps logs for errors.
Check the pipeline run history for errors.
Check the pipeline configuration for errors.
Check the loop and condition syntax for errors.
Check the parameter and variable values for errors.

Q: Can I use Azure DevOps YAML loops with other Azure DevOps features?

A: Yes, you can use Azure DevOps YAML loops with other Azure DevOps features, such as:

Azure Pipelines
Azure Repos
Azure Test Plans
Azure Artifacts

Q: Are there any best practices for using Azure DevOps YAML loops?

A: Yes, here are some best practices for using Azure DevOps YAML loops:

Use meaningful names for your parameters and variables.
Use clear and concise syntax for your loops and conditions.
Use the condition section to specify when the loop should be executed.
Use the parameters section to define input parameters that can be used during the pipeline run.
Use the steps section to define the tasks that will be executed during the pipeline run.

Q: Can I use Azure DevOps YAML loops with other YAML files?

A: Yes, you can use Azure DevOps YAML loops with other YAML files, such as:

Azure Pipelines YAML files
Azure Repos YAML files
Azure Test Plans YAML files
Azure Artifacts YAML files

Q: Are there any limitations to using Azure DevOps YAML loops?

A: Yes, there are some limitations to using Azure DevOps YAML loops, including:

Limited support for complex loops and conditions.
Limited support for loops with multiple iterations.
Limited support for loops with conditional execution.

Conclusion

In this article, we have answered some frequently asked questions about Azure DevOps YAML loops. We have covered topics such as defining a pipeline with a loop, using a loop with a parameter, using a condition with a loop, and troubleshooting issues with Azure DevOps YAML loops. We have also provided some best practices for using Azure DevOps YAML loops and discussed some limitations to using Azure DevOps YAML loops.