plan/plan.go
// Copyright © 2016 Asteris, LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package plan
import (
"errors"
"fmt"
"github.com/asteris-llc/converge/graph"
"github.com/asteris-llc/converge/graph/node"
"github.com/asteris-llc/converge/render"
"golang.org/x/net/context"
)
// ErrTreeContainsErrors is a signal value to indicate errors in the graph
var ErrTreeContainsErrors = errors.New("plan has errors, check graph")
// Plan the execution of a Graph of resource.Tasks
func Plan(ctx context.Context, in *graph.Graph) (*graph.Graph, error) {
return WithNotify(ctx, in, nil)
}
// WithNotify is plan, but with a notification feature
func WithNotify(ctx context.Context, in *graph.Graph, notify *graph.Notifier) (*graph.Graph, error) {
var hasErrors error
out, err := in.Transform(ctx,
notify.Transform(func(meta *node.Node, out *graph.Graph) error {
renderingPlant, err := render.NewFactory(ctx, in)
if err != nil {
return err
}
renderingPlant.Graph = out
pipeline := Pipeline(ctx, out, meta.ID, renderingPlant)
val, pipelineErr := pipeline.Exec(ctx, meta.Value())
if pipelineErr != nil {
return pipelineErr
}
asResult, ok := val.(*Result)
if !ok {
return fmt.Errorf("expected asResult but got %T", val)
}
if nil != asResult.Error() {
hasErrors = ErrTreeContainsErrors
}
out.Add(meta.WithValue(asResult))
return nil
}),
)
if err != nil {
return out, err
}
return out, hasErrors
}