Plugin Types

Porter is extensible and supports a couple extension points where you can alter its default behavior. Plugins implement a well-defined interface and can be switched by editing Porter’s configuration file.

Storage

Storage plugins let you persist files created by Porter to an alternative location, instead of to the local filesystem under ~/.porter. By default, credential and parameter sets are saved to the /credentials and /parameters directories under ~/.porter. Installation records of a bundle being executed, including claim receipts, action results and outputs, are saved to the /claims, /results and /outputs directories under ~/.porter.

A storage plugin can implement the plugins.StorageProtocol interface and change where those files are saved. For example, the Azure plugin saves them to Azure Blob Storage.

Secrets

Secrets plugins make it easier to securely store and share secret values and then inject them into a bundle. Currently secrets can be injected as credentials and parameters. By default, secrets are resolved against the localhost: environment variables, files, commands and hard-coded values.

During bundle execution, any parameters or bundle outputs that contains sensitive data are stored into a secret store that is configured by the user. Credentials are never persisted, either to Porter’s database or secret store, and are always retrieved just-in-time before the bundle is run.

A secrets plugin can implement the plugins.SecretsProtocol interface and resolve credentials from remote and ideally more secure locations. For example, the Azure plugin resolves secrets from Azure Key Vault.