Secrets

Secrets are a flavor of Configs focusing on sensitive data, with specific constraint for this usage.

Services can only access secrets when explicitly granted by a secrets attribute within the services top-level element.

The top-level secrets declaration defines or references sensitive data that is granted to the services in your Compose application. The source of the secret is either file or environment.

• file: The secret is created with the contents of the file at the specified path.
• environment: The secret is created with the value of an environment variable on the host. This is only supported by Docker Compose. It is not supported when deploying with docker stack deploy.

Example 1

server-certificate secret is created as <project_name>_server-certificate when the application is deployed, by registering content of the server.cert as a platform secret.

secrets:
  server-certificate:
    file: ./server.cert

Example 2

token secret is created as <project_name>_token when the application is deployed, by registering the content of the OAUTH_TOKEN environment variable as a platform secret.

secrets:
  token:
    environment: "OAUTH_TOKEN"

Note

environment secrets are not supported when deploying with docker stack deploy. Use file or external as the secret source instead.

Additional resources

For more information, see How to use secrets in Compose.