Naming, aliases, and push-to-env

Naming convention

• Class name prefix: portion before Settings, uppercased (e.g., MongoSettings → MONGO).
• Field name: camelCase transformed to UPPER_SNAKE_CASE (e.g., connectionString → CONNECTION_STRING).
• Environment variable: <PREFIX>_<FIELD>.

export class MongoSettings extends BaseSettings {
  @setting.string()
  connectionString = 'mongodb://localhost:27017'
}
// → MONGO_CONNECTION_STRING

Aliases

Use @alias('ENV_VAR_NAME') to map a field to a specific env var. Aliases take precedence when present.

export class PubsubSettings extends BaseSettings {
  @setting.string()
  @alias('GOOGLE_CLOUD_PROJECT')
  projectId = 'my-project'
}

push-to-env

Use @pushToEnv() to always write a field’s value into process.env during load (overwriting if present). This helps integrate with tools that expect those variables.

export class SmtpSettings extends BaseSettings {
  @setting.string()
  @pushToEnv()
  host = 'localhost'
}

Notes

• Use sparingly; it’s a convenience to help local tooling.
• If combined with @alias, the alias name is used for the env var.
• Values are overwritten if the variable already exists in process.env.