References and env

dpl config values can contain references.

runtime:
  env:
    DATABASE_URL: ${app-db:url}
    API_TOKEN: ${secret:api-token}

dpl resolves these values during deploy. Broken references fail dpl check and dpl deploy.

Reference syntax

${secret:<secret-name>}
${<unit-name>:<key>}

Use $$ when you need a literal dollar sign:

PRICE_TEXT: "cost: $$5"

Secret references

env:
  API_TOKEN: ${secret:api-token}
  DB_PASSWORD: ${secret:db/prod-password}

Secret names can be grouped with /. Each segment must use lowercase letters, digits, and single dashes, the same rules as unit names.

Unit references

app exports:

Key	Meaning
url	http://dpl--<unit>:<port>
socket	dpl--<unit>:<port>
export	Static export path inside the nginx container.

db exports:

Key	Meaning
name	Database name.
user	Login user.
password	Decrypted login password.
host	Scoped db-server container name.
port	Database engine port.
url	Full database URL.

db-server, http-server, and domain do not export values.

Environment variable names

Environment variable names must use letters, digits, and underscores. They cannot start with a digit.

Valid:

env:
  NODE_ENV: production
  DB_PORT: 5432
  _PRIVATE_FLAG: true

Invalid:

env:
  1TOKEN: bad
  DB-PORT: bad

Numbers and booleans are accepted in YAML and converted to strings.