Running Pipelines for Changes to non-IaC file dependencies
Pipelines runs plan/applies based on changes to your units in your IaC repository. Intuitively, if you make a change to path/to/my/unit/terragrunt.hcl then Pipelines will run plan/apply in /path/to/my/unit. Pipelines also supports running run-all when consolidation is enabled.
However, there are some cases where you may want to run Pipelines for changes to files that are not part of your IaC. For example, you may have a terragrunt.hcl file that imports data from a tags.yaml file. If you make a change to the tags.yaml file, you may want to run Pipelines to plan/apply the changes to the associated terragrunt.hcl file. This page documents how to configure pipelines to automatically run plan/apply when only these data files are changed.
Configuration
This feature is available when using Pipelines with Terragrunt version 0.68.13 and later.
Pipelines will automatically detect, based on git commit history, when data files have changed and emit a FileChanged change. This will create a new execution in your CI flow that will invoke Terragrunt with the queue-include-units-reading option set to the files that have changed. Terragrunt will then scan your code for units that depend on the changed files and add them to the plan/apply.
Note that Terragrunt will only be able to determine which units read the data file if that file is read using a built-in function such as read_terragrunt_config or is in a include, dependency, or dependencies block. You may want to use the mark_as_read function to explicitly ensure that Terragrunt knows to include your unit when a particular data file is changed.