mirror of https://github.com/hashicorp/consul
75 lines
2.4 KiB
Go
75 lines
2.4 KiB
Go
|
// Copyright (c) HashiCorp, Inc.
|
||
|
|
// SPDX-License-Identifier: BUSL-1.1
|
||
|
|
|
||
|
|
package dependency
|
||
|
|
|
||
|
|
import (
|
||
|
|
"context"
|
||
|
|
|
||
|
|
"github.com/hashicorp/consul/internal/controller"
|
||
|
|
"github.com/hashicorp/consul/proto-public/pbresource"
|
||
|
|
)
|
||
|
|
|
||
|
|
// DependencyTransform is used when the incoming resource from a watch needs to
|
||
|
|
// be transformed to a different resource or set of resources and then have
|
||
|
|
// a DependencyMapper executed on each element in that result set. This should
|
||
|
|
// only be needed for dealing with more complex dependency relationships where
|
||
|
|
// the managed type and watched type are not directly related.
|
||
|
|
type DependencyTransform func(
|
||
|
|
ctx context.Context,
|
||
|
|
rt controller.Runtime,
|
||
|
|
res *pbresource.Resource,
|
||
|
|
) ([]*pbresource.Resource, error)
|
||
|
|
|
||
|
|
// MapperWithTransform will execute the provided DependencyTransform and then execute
|
||
|
|
// the provided DependencyMapper once for each of the resources output by the transform.
|
||
|
|
// The DependencyMapper outputs will then be concatenated together to form the whole
|
||
|
|
// set of mapped Requests.
|
||
|
|
func MapperWithTransform(mapper controller.DependencyMapper, transform DependencyTransform) controller.DependencyMapper {
|
||
|
|
return func(ctx context.Context, rt controller.Runtime, res *pbresource.Resource) ([]controller.Request, error) {
|
||
|
|
transformed, err := transform(ctx, rt, res)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
var reqs []controller.Request
|
||
|
|
for _, res := range transformed {
|
||
|
|
newReqs, err := mapper(ctx, rt, res)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
reqs = append(reqs, newReqs...)
|
||
|
|
}
|
||
|
|
|
||
|
|
return reqs, nil
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// TransformChain takes a set of transformers and will execute them as a pipeline.
|
||
|
|
// The first transformer will output some resources. Those resources will then be
|
||
|
|
// used as inputs to the next transform. The chain will then continue until all
|
||
|
|
// transformers have been run.
|
||
|
|
func TransformChain(transformers ...DependencyTransform) DependencyTransform {
|
||
|
|
return func(ctx context.Context, rt controller.Runtime, res *pbresource.Resource) ([]*pbresource.Resource, error) {
|
||
|
|
toTransform := []*pbresource.Resource{res}
|
||
|
|
|
||
|
|
for _, transform := range transformers {
|
||
|
|
var nextResources []*pbresource.Resource
|
||
|
|
|
||
|
|
for _, res := range toTransform {
|
||
|
|
next, err := transform(ctx, rt, res)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
nextResources = append(nextResources, next...)
|
||
|
|
}
|
||
|
|
|
||
|
|
toTransform = nextResources
|
||
|
|
}
|
||
|
|
|
||
|
|
return toTransform, nil
|
||
|
|
}
|
||
|
|
}
|