Files
rkt/pkg/aci/render.go

78 lines
2.6 KiB
Go

// Copyright 2015 The rkt Authors
//
// 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 aci
import (
"fmt"
ptar "github.com/coreos/rkt/pkg/tar"
"github.com/coreos/rkt/Godeps/_workspace/src/github.com/appc/spec/pkg/acirenderer"
"github.com/coreos/rkt/Godeps/_workspace/src/github.com/appc/spec/schema/types"
)
// Given an imageID, start with the matching image available in the store,
// build its dependency list and render it inside dir
func RenderACIWithImageID(imageID types.Hash, dir string, ap acirenderer.ACIRegistry) error {
renderedACI, err := acirenderer.GetRenderedACIWithImageID(imageID, ap)
if err != nil {
return err
}
return renderImage(renderedACI, dir, ap)
}
// Given an image app name and optional labels, get the best matching image
// available in the store, build its dependency list and render it inside dir
func RenderACI(name types.ACName, labels types.Labels, dir string, ap acirenderer.ACIRegistry) error {
renderedACI, err := acirenderer.GetRenderedACI(name, labels, ap)
if err != nil {
return err
}
return renderImage(renderedACI, dir, ap)
}
// Given an already populated dependency list, it will extract, under the provided
// directory, the rendered ACI
func RenderACIFromList(imgs acirenderer.Images, dir string, ap acirenderer.ACIProvider) error {
renderedACI, err := acirenderer.GetRenderedACIFromList(imgs, ap)
if err != nil {
return err
}
return renderImage(renderedACI, dir, ap)
}
// Given a RenderedACI, it will extract, under the provided directory, the
// needed files from the right source ACI.
// The manifest will be extracted from the upper ACI.
// No file overwriting is done as it should usually be called
// providing an empty directory.
func renderImage(renderedACI acirenderer.RenderedACI, dir string, ap acirenderer.ACIProvider) error {
for _, ra := range renderedACI {
rs, err := ap.ReadStream(ra.Key)
if err != nil {
return err
}
// Overwrite is not needed. If a file needs to be overwritten then the renderedACI builder has a bug
if err := ptar.ExtractTar(rs, dir, false, ra.FileMap); err != nil {
rs.Close()
return fmt.Errorf("error extracting ACI: %v", err)
}
rs.Close()
}
return nil
}