Environment Variables

The container runtime automatically sets the following variables:

• CLOUDFLARE_APPLICATION_ID - the ID of the Containers application
• CLOUDFLARE_COUNTRY_A2 - the ISO 3166-1 Alpha 2 code ↗ of a country the container is placed in
• CLOUDFLARE_LOCATION - a name of a location the container is placed in
• CLOUDFLARE_REGION - a region name
• CLOUDFLARE_DURABLE_OBJECT_ID - the ID of the Durable Object instance that the container is bound to. You can use this to identify particular container instances on the dashboard.

You can set environment variables when defining a Container in your Worker, or when starting a container instance.

For example:

class MyContainer extends Container {
	defaultPort = 4000;
	envVars = {
		MY_CUSTOM_VAR: "value",
		ANOTHER_VAR: "another_value",
	};
}

More details about defining environment variables and secrets can be found in this example.