codeocean/docs/environment_variables.md

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
SENTRY_JAVASCRIPT_DSN		Specifies the Sentry error reporting endpoint for the frontend used by browsers
SENTRY_CURRENT_ENV		Specifies the Sentry environment used for error reporting
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 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 Vagrant VM 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)