Metadata

Encore tries to provide a cloud-agnostic environment, but sometimes it's useful to know more about where your code is running. Encore.rs exposes metadata about the application, its environment, build, and deployment through encore::env::app_meta(), also available as encore::app_meta().

Application metadata

app_meta() returns a &'static AppMeta. It's computed once, when the runtime is initialized, so repeated calls are free.

let md = encore::app_meta();
println!("running {} in {}", md.app_id, md.environment.name);

AppMeta has these fields:

Environment

md.environment is an EnvironmentMeta with:

• name: the environment's name. For encore run it's local, and for encore test it's test.
• r#type: an EnvironmentType, one of Production, Development, Ephemeral (such as preview environments), or Test. encore run reports Development.
• cloud: a CloudProvider, one of AWS, GCP, Azure, Encore, or Local. Locally it's Local.

These enums don't implement PartialEq, so compare them with matches! or a match:

use encore::env::EnvironmentType;

let is_prod = matches!(encore::app_meta().environment.r#type, EnvironmentType::Production);

Gateways

An app can have several gateways, so there's no single base URL. Look up the one you mean by name; each GatewayMeta has a name and a base_url:

if let Some(gw) = encore::app_meta().gateway("api") {
    println!("api is served at {}", gw.base_url);
}

A process that no gateway serves, such as a worker, has an empty gateways map.

Example use cases

Using cloud-specific services

Encore doesn't natively support every service each cloud offers. Using the environment's cloud provider, you can choose an implementation per cloud. For example, to write audit logs to a data warehouse:

use encore::env::CloudProvider;

async fn audit(action: &str, user_id: &str) -> Result<(), AuditError> {
    match encore::app_meta().environment.cloud {
        CloudProvider::AWS => write_to_redshift(action, user_id).await,
        CloudProvider::GCP => write_to_bigquery(action, user_id).await,
        CloudProvider::Local => write_to_file(action, user_id).await,
        CloudProvider::Azure | CloudProvider::Encore => Err(AuditError::Unsupported),
    }
}

Checking the environment type

When building a signup flow, you may want to skip email verification during development and in tests:

use encore::env::EnvironmentType;

async fn finish_signup(user_id: &str) -> Result<(), SignupError> {
    match encore::app_meta().environment.r#type {
        EnvironmentType::Development | EnvironmentType::Test => {
            mark_email_verified(user_id).await
        }
        _ => send_verification_email(user_id).await,
    }
}

For values that differ per environment, consider configuration instead: overlay files per environment type or environment name keep the differences out of your code.