open-vault/logical/logical.go

83 lines
3.4 KiB
Go

package logical
import log "github.com/mgutz/logxi/v1"
// Backend interface must be implemented to be "mountable" at
// a given path. Requests flow through a router which has various mount
// points that flow to a logical backend. The logic of each backend is flexible,
// and this is what allows materialized keys to function. There can be specialized
// logical backends for various upstreams (Consul, PostgreSQL, MySQL, etc) that can
// interact with remote APIs to generate keys dynamically. This interface also
// allows for a "procfs" like interaction, as internal state can be exposed by
// acting like a logical backend and being mounted.
type Backend interface {
// HandleRequest is used to handle a request and generate a response.
// The backends must check the operation type and handle appropriately.
HandleRequest(*Request) (*Response, error)
// SpecialPaths is a list of paths that are special in some way.
// See PathType for the types of special paths. The key is the type
// of the special path, and the value is a list of paths for this type.
// This is not a regular expression but is an exact match. If the path
// ends in '*' then it is a prefix-based match. The '*' can only appear
// at the end.
SpecialPaths() *Paths
// System provides an interface to access certain system configuration
// information, such as globally configured default and max lease TTLs.
System() SystemView
// HandleExistenceCheck is used to handle a request and generate a response
// indicating whether the given path exists or not; this is used to
// understand whether the request must have a Create or Update capability
// ACL applied. The first bool indicates whether an existence check
// function was found for the backend; the second indicates whether, if an
// existence check function was found, the item exists or not.
HandleExistenceCheck(*Request) (bool, bool, error)
// Cleanup is invoked during an unmount of a backend to allow it to
// handle any cleanup like connection closing or releasing of file handles.
Cleanup()
// Initialize is invoked after a backend is created. It is the place to run
// any operations requiring storage; these should not be in the factory.
Initialize() error
// InvalidateKey may be invoked when an object is modified that belongs
// to the backend. The backend can use this to clear any caches or reset
// internal state as needed.
InvalidateKey(key string)
}
// BackendConfig is provided to the factory to initialize the backend
type BackendConfig struct {
// View should not be stored, and should only be used for initialization
StorageView Storage
// The backend should use this logger. The log should not contain any secrets.
Logger log.Logger
// System provides a view into a subset of safe system information that
// is useful for backends, such as the default/max lease TTLs
System SystemView
// Config is the opaque user configuration provided when mounting
Config map[string]string
}
// Factory is the factory function to create a logical backend.
type Factory func(*BackendConfig) (Backend, error)
// Paths is the structure of special paths that is used for SpecialPaths.
type Paths struct {
// Root are the paths that require a root token to access
Root []string
// Unauthenticated are the paths that can be accessed without any auth.
Unauthenticated []string
// LocalStorage are paths (prefixes) that are local to this instance; this
// indicates that these paths should not be replicated
LocalStorage []string
}