# Environment Variables

The following environment variables are specifically support in CodeOcean and are used to configure the application in addition to the setting files under `config/`.

| Environment Variable 	| Default 	| Description 	|
|-	|-	|-	|
| `RAILS_ENV` 	| `development` 	| Specifies the Rails environment which can be configured using the files in `config/environments` 	|
| `RAILS_RELATIVE_URL_ROOT` 	| `/` 	| Specifies the subpath of the application, used for links and assets 	|
| `SENTRY_DSN` 	| `` 	| Specifies the Sentry error reporting endpoint for the Rails server 	|
| `RAILS_LOG_TO_STDOUT` 	| `false` in `production` 	| Enables the server to print log output to the command line 	|
| `RAILS_SERVE_STATIC_FILES` 	| `true` in `development` and `test`<br>`false` in `production` and `staging` 	| Specifies whether the Rails server should be able to handle requests for non-dynamic resources (e.g., assets) 	|
| `BACKTRACE` 	| `false` 	| Enables more verbose log output from framework code during debugging 	|
| `TRUSTED_IP` 	| ` ` in `development` 	| Enables `BetterErrors` for the given IP addresses during development 	|
| `LISTEN_ADDRESS` 	| `127.0.0.1` in `development` 	| Specifies the IP address the server should attach to during development 	|
| `HEADLESS_TEST` 	| `false` 	| Enables the test environment to work without a window manager for feature tests (e.g., using Vagrant) 	|