Environment Variables

Environment variables are composed of key-value pairs set externally from your source code. They can influence the behavior of the web application, providing a way to adjust its configuration without changing the codebase. Each value can be modified based on the specific Atlas environment.

Modifications to environment variables do not retroactively affect past builds. They are effective only for subsequent builds.

Managing environment variables

To add new variables visit the Atlas Environment Details page and click the Go to variables link of the Variables card.

On first entry to this page you will see an empty Environment Variables table in the non-edit mode. To add a row select the Add environment variable button.

Enter a key and value for each of your variable rows. To add further rows, while in edit mode, press Add Variable and input additional key-value pairs. Then click Save changes to confirm.

Upon saving the table your changes are persisted but not yet in use, so you will be prompted to redeploy the Atlas Environment with the latest variables. This is optional but if you redeploy you will be taken to the Environment Details page & a redeploy will commence.

Once the first variable row(s) has been added and saved, with or without redeploy, you will see the variable(s) in the non-edit mode version of the table. To modify this table again simply select the Add environment variable button again . Each time you save you will have to choose whether to redeploy, as before.

You can download your existing environment variables list when not in edit mode. This is done via the download icon, below the Add environment Variable button.

This presents you with a popup modal with 2 options for download format: CSV & .env.

You can modify existing variables by entering edit mode, accessible through the edit icon of the table, below the Add environment variable button. When in edit mode each row can be deleted or modified & there is a quick Add variable button, which works as the previously-mentioned Add environment variable one.

You can remove a variable by clicking on the trash icon while in edit mode.

Limitations

Reserved variables and namespaces

Atlas reserves some environment variables and prefixes. You cannot use these for your own variables:

• PORT
• WPE_ prefix
• ATLAS_METADATA prefix

If you try to use these reserved keys, Atlas will display a warning and won’t save the variable.

Allowed format of keys

Environment variables’ keys on Atlas must match the following regex:

[a-zA-Z_]{1,}[a-zA-Z0-9_]*.

Special environment variables

The table below lists the environment variables for customizing operations in Atlas:

Environment Variable	Description	Example
ATLAS_NO_PURGE_CDN	Omit purging the CDN cache after deployments. Note: this may impact your site’s content freshness.	true

System environment variables

Atlas automatically generates a collection of environment variables to provide users with metadata about their environments. This includes variables such as the Build ID or a flag that signifies whether the environment in question is a preview or production environment. You can find the complete list of system environment variables in the table below:

Environment Variable	Description	Example
ATLAS_METADATA_SOURCE	Source control provider	github
ATLAS_METADATA_REPOSITORY	Git repository name and owner	some-user/repo-name
ATLAS_METADATA_APP_NAME	Name of the Atlas application	my-app
ATLAS_METADATA_ENV_NAME	Name of the Atlas environment	main-env
ATLAS_METADATA_COMMIT_SHA	Commit identifier for the current build	4e6f58b
ATLAS_METADATA_ENV_BRANCH	Git branch used for the current build	main
ATLAS_METADATA_PREVIEW_ENV	Flag that indicates if the environment is a ‘preview’ type	true
ATLAS_METADATA_ENV_ID	Unique identifier for the Atlas environment	026bbe63-8043-1c3e-00e5-d95c5a12aa32
ATLAS_METADATA_BUILD_ID	Identifier for the latest build	5f42ce7c-b894-887d-1b9e-69d2429acbdd
ATLAS_METADATA_CLEAN_BUILD	Indicates if the build is a ‘clean’ build	false