pulumi/pkg/resource/plugin/provider.go
2017-06-26 14:46:34 -07:00

51 lines
2.9 KiB
Go

// Copyright 2016-2017, Pulumi Corporation. All rights reserved.
package plugin
import (
"io"
"github.com/pulumi/lumi/pkg/resource"
"github.com/pulumi/lumi/pkg/tokens"
)
// Provider presents a simple interface for orchestrating resource create, reead, update, and delete operations. Each
// provider understands how to handle all of the resource types within a single package.
//
// This interface hides some of the messiness of the underlying machinery, since providers are behind an RPC boundary.
//
// It is important to note that provider operations are not transactional. (Some providers might decide to offer
// transactional semantics, but such a provider is a rare treat.) As a result, failures in the operations below can
// range from benign to catastrophic (possibly leaving behind a corrupt resource). It is up to the provider to make a
// best effort to ensure catastrophes do not occur. The errors returned from mutating operations indicate both the
// underlying error condition in addition to a bit indicating whether the operation was successfully rolled back.
type Provider interface {
// Closer closes any underlying OS resources associated with this provider (like processes, RPC channels, etc).
io.Closer
// Pkg fetches this provider's package.
Pkg() tokens.Package
// Check validates that the given property bag is valid for a resource of the given type.
Check(t tokens.Type, props resource.PropertyMap) ([]CheckFailure, error)
// Name names a given resource. Sometimes this will be assigned by a developer, and so the provider
// simply fetches it from the property bag; other times, the provider will assign this based on its own algorithm.
// In any case, resources with the same name must be safe to use interchangeably with one another.
Name(t tokens.Type, props resource.PropertyMap) (tokens.QName, error)
// Create allocates a new instance of the provided resource and returns its unique resource.ID.
Create(t tokens.Type, props resource.PropertyMap) (resource.ID, resource.Status, error)
// Get reads the instance state identified by res and returns it.
Get(t tokens.Type, id resource.ID) (resource.PropertyMap, error)
// InspectChange checks what impacts a hypothetical update will have on the resource's properties.
InspectChange(t tokens.Type, id resource.ID,
olds resource.PropertyMap, news resource.PropertyMap) ([]resource.PropertyKey, resource.PropertyMap, error)
// Update updates an existing resource with new values.
Update(t tokens.Type, id resource.ID,
olds resource.PropertyMap, news resource.PropertyMap) (resource.Status, error)
// Delete tears down an existing resource.
Delete(t tokens.Type, id resource.ID) (resource.Status, error)
}
// CheckFailure indicates that a call to check failed; it contains the property and reason for the failure.
type CheckFailure struct {
Property resource.PropertyKey // the property that failed checking.
Reason string // the reason the property failed to check.
}