Metadata

While Encore tries to provide a cloud-agnostic environment, sometimes it's helpful to know more about the environment your application is running in. For this reason Encore provides an API for accessing metadata about the application and the environment it's running in as part of the encore.dev package.

Application Metadata

Calling appMeta() from the encore.dev package returns an object that contains information about the application, including:

• appID - the application name.
• apiBaseURL - the URL the application API can be publicly accessed on.
• environment - the environment the application is currently running in.
• build - the revision information of the build from the version control system.
• deploy - the deployment ID and when this version of the app was deployed.

Example Use Cases

Using Cloud Specific Services

All the clouds contain a large number of services, not all of which Encore natively supports.

By using information about the environment, you can define the implementation of these and use different services for each environment's provider.

For instance if you are pushing audit logs into a data warehouse, when running on GCP you could use BigQuery, but when running on AWS you could use Redshift, when running locally you could simply write them to a file.

import { appMeta } from "encore.dev";

// Emit an audit event.
async function audit(userID: string, event: Record<string, any>) {
  const cloud = appMeta().environment.cloud;
  switch (cloud) {
    case "aws":
      return writeIntoRedshift(userID, event);
    case "gcp":
      return writeIntoBigQuery(userID, event);
    case "local":
      return writeIntoFile(userID, event);
    default:
      throw new Error(`unknown cloud: ${cloud}`);
  }
}

Checking Environment type

When implementing a signup system, you may want to skip email verification on user signups when developing the application. Using the appMeta API, we can check the environment and decide whether to send an email or simply mark the user as verified upon signup.

import { appMeta } from "encore.dev";

export const signup = api(
  { expose: true },
  async (params: SignupParams): Promise<SignupResponse> => {
    // more code...

    // If this is a testing environment, skip sending the verification email.
    switch (appMeta().environment.type) {
      case ("test", "development"):
        await markEmailVerified(userID);
        break;
      default:
        await sendVerificationEmail(userID);
        break;
    }

    // more code...
  },
);