ref: d4fc70a3b320a55c4f571eed806d5ad5fdf1ef14
dir: /resources/resource.go/
// Copyright 2019 The Hugo Authors. All rights reserved.
//
// 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 resources
import (
"fmt"
"io"
"io/ioutil"
"os"
"path"
"path/filepath"
"sync"
"github.com/gohugoio/hugo/resources/internal"
"github.com/gohugoio/hugo/common/herrors"
"github.com/gohugoio/hugo/hugofs"
"github.com/gohugoio/hugo/media"
"github.com/gohugoio/hugo/source"
"github.com/pkg/errors"
"github.com/gohugoio/hugo/common/hugio"
"github.com/gohugoio/hugo/common/maps"
"github.com/gohugoio/hugo/resources/page"
"github.com/gohugoio/hugo/resources/resource"
"github.com/spf13/afero"
"github.com/gohugoio/hugo/helpers"
)
var (
_ resource.ContentResource = (*genericResource)(nil)
_ resource.ReadSeekCloserResource = (*genericResource)(nil)
_ resource.Resource = (*genericResource)(nil)
_ resource.Source = (*genericResource)(nil)
_ resource.Cloner = (*genericResource)(nil)
_ resource.ResourcesLanguageMerger = (*resource.Resources)(nil)
_ permalinker = (*genericResource)(nil)
_ resource.Identifier = (*genericResource)(nil)
_ fileInfo = (*genericResource)(nil)
)
type ResourceSourceDescriptor struct {
// TargetPaths is a callback to fetch paths's relative to its owner.
TargetPaths func() page.TargetPaths
// Need one of these to load the resource content.
SourceFile source.File
OpenReadSeekCloser resource.OpenReadSeekCloser
FileInfo os.FileInfo
// If OpenReadSeekerCloser is not set, we use this to open the file.
SourceFilename string
Fs afero.Fs
// The relative target filename without any language code.
RelTargetFilename string
// Any base paths prepended to the target path. This will also typically be the
// language code, but setting it here means that it should not have any effect on
// the permalink.
// This may be several values. In multihost mode we may publish the same resources to
// multiple targets.
TargetBasePaths []string
// Delay publishing until either Permalink or RelPermalink is called. Maybe never.
LazyPublish bool
}
func (r ResourceSourceDescriptor) Filename() string {
if r.SourceFile != nil {
return r.SourceFile.Filename()
}
return r.SourceFilename
}
type ResourceTransformer interface {
resource.Resource
Transformer
}
type Transformer interface {
Transform(...ResourceTransformation) (ResourceTransformer, error)
}
func NewFeatureNotAvailableTransformer(key string, elements ...interface{}) ResourceTransformation {
return transformerNotAvailable{
key: internal.NewResourceTransformationKey(key, elements...),
}
}
type transformerNotAvailable struct {
key internal.ResourceTransformationKey
}
func (t transformerNotAvailable) Transform(ctx *ResourceTransformationCtx) error {
return herrors.ErrFeatureNotAvailable
}
func (t transformerNotAvailable) Key() internal.ResourceTransformationKey {
return t.key
}
type baseResourceResource interface {
resource.Cloner
resource.ContentProvider
resource.Resource
resource.Identifier
}
type baseResourceInternal interface {
resource.Source
fileInfo
metaAssigner
targetPather
ReadSeekCloser() (hugio.ReadSeekCloser, error)
// Internal
cloneWithUpdates(*transformationUpdate) (baseResource, error)
tryTransformedFileCache(key string, u *transformationUpdate) io.ReadCloser
specProvider
getResourcePaths() *resourcePathDescriptor
getTargetFilenames() []string
openDestinationsForWriting() (io.WriteCloser, error)
openPublishFileForWriting(relTargetPath string) (io.WriteCloser, error)
relTargetPathForRel(rel string, addBaseTargetPath, isAbs, isURL bool) string
}
type specProvider interface {
getSpec() *Spec
}
type baseResource interface {
baseResourceResource
baseResourceInternal
}
type commonResource struct {
}
// Slice is not meant to be used externally. It's a bridge function
// for the template functions. See collections.Slice.
func (commonResource) Slice(in interface{}) (interface{}, error) {
switch items := in.(type) {
case resource.Resources:
return items, nil
case []interface{}:
groups := make(resource.Resources, len(items))
for i, v := range items {
g, ok := v.(resource.Resource)
if !ok {
return nil, fmt.Errorf("type %T is not a Resource", v)
}
groups[i] = g
{
}
}
return groups, nil
default:
return nil, fmt.Errorf("invalid slice type %T", items)
}
}
type dirFile struct {
// This is the directory component with Unix-style slashes.
dir string
// This is the file component.
file string
}
func (d dirFile) path() string {
return path.Join(d.dir, d.file)
}
type fileInfo interface {
getSourceFilename() string
setSourceFilename(string)
setSourceFs(afero.Fs)
getFileInfo() hugofs.FileMetaInfo
hash() (string, error)
size() int
}
// genericResource represents a generic linkable resource.
type genericResource struct {
*resourcePathDescriptor
*resourceFileInfo
*resourceContent
spec *Spec
title string
name string
params map[string]interface{}
data map[string]interface{}
resourceType string
mediaType media.Type
}
func (l *genericResource) Clone() resource.Resource {
return l.clone()
}
func (l *genericResource) Content() (interface{}, error) {
if err := l.initContent(); err != nil {
return nil, err
}
return l.content, nil
}
func (l *genericResource) Data() interface{} {
return l.data
}
func (l *genericResource) Key() string {
return l.RelPermalink()
}
func (l *genericResource) MediaType() media.Type {
return l.mediaType
}
func (l *genericResource) setMediaType(mediaType media.Type) {
l.mediaType = mediaType
}
func (l *genericResource) Name() string {
return l.name
}
func (l *genericResource) Params() maps.Params {
return l.params
}
func (l *genericResource) Permalink() string {
return l.spec.PermalinkForBaseURL(l.relPermalinkForRel(l.relTargetDirFile.path(), true), l.spec.BaseURL.HostURL())
}
func (l *genericResource) Publish() error {
var err error
l.publishInit.Do(func() {
var fr hugio.ReadSeekCloser
fr, err = l.ReadSeekCloser()
if err != nil {
return
}
defer fr.Close()
var fw io.WriteCloser
fw, err = helpers.OpenFilesForWriting(l.spec.BaseFs.PublishFs, l.getTargetFilenames()...)
if err != nil {
return
}
defer fw.Close()
_, err = io.Copy(fw, fr)
})
return err
}
func (l *genericResource) RelPermalink() string {
return l.relPermalinkFor(l.relTargetDirFile.path())
}
func (l *genericResource) ResourceType() string {
return l.resourceType
}
func (l *genericResource) String() string {
return fmt.Sprintf("Resource(%s: %s)", l.resourceType, l.name)
}
// Path is stored with Unix style slashes.
func (l *genericResource) TargetPath() string {
return l.relTargetDirFile.path()
}
func (l *genericResource) Title() string {
return l.title
}
func (l *genericResource) createBasePath(rel string, isURL bool) string {
if l.targetPathBuilder == nil {
return rel
}
tp := l.targetPathBuilder()
if isURL {
return path.Join(tp.SubResourceBaseLink, rel)
}
// TODO(bep) path
return path.Join(filepath.ToSlash(tp.SubResourceBaseTarget), rel)
}
func (l *genericResource) initContent() error {
var err error
l.contentInit.Do(func() {
var r hugio.ReadSeekCloser
r, err = l.ReadSeekCloser()
if err != nil {
return
}
defer r.Close()
var b []byte
b, err = ioutil.ReadAll(r)
if err != nil {
return
}
l.content = string(b)
})
return err
}
func (l *genericResource) setName(name string) {
l.name = name
}
func (l *genericResource) getResourcePaths() *resourcePathDescriptor {
return l.resourcePathDescriptor
}
func (l *genericResource) getSpec() *Spec {
return l.spec
}
func (l *genericResource) getTargetFilenames() []string {
paths := l.relTargetPaths()
for i, p := range paths {
paths[i] = filepath.Clean(p)
}
return paths
}
func (l *genericResource) setTitle(title string) {
l.title = title
}
func (r *genericResource) tryTransformedFileCache(key string, u *transformationUpdate) io.ReadCloser {
fi, f, meta, found := r.spec.ResourceCache.getFromFile(key)
if !found {
return nil
}
u.sourceFilename = &fi.Name
mt, _ := r.spec.MediaTypes.GetByType(meta.MediaTypeV)
u.mediaType = mt
u.data = meta.MetaData
u.targetPath = meta.Target
return f
}
func (r *genericResource) mergeData(in map[string]interface{}) {
if len(in) == 0 {
return
}
if r.data == nil {
r.data = make(map[string]interface{})
}
for k, v := range in {
if _, found := r.data[k]; !found {
r.data[k] = v
}
}
}
func (rc *genericResource) cloneWithUpdates(u *transformationUpdate) (baseResource, error) {
r := rc.clone()
if u.content != nil {
r.contentInit.Do(func() {
r.content = *u.content
r.openReadSeekerCloser = func() (hugio.ReadSeekCloser, error) {
return hugio.NewReadSeekerNoOpCloserFromString(r.content), nil
}
})
}
r.mediaType = u.mediaType
if u.sourceFilename != nil {
r.setSourceFilename(*u.sourceFilename)
}
if u.sourceFs != nil {
r.setSourceFs(u.sourceFs)
}
if u.targetPath == "" {
return nil, errors.New("missing targetPath")
}
fpath, fname := path.Split(u.targetPath)
r.resourcePathDescriptor.relTargetDirFile = dirFile{dir: fpath, file: fname}
r.mergeData(u.data)
return r, nil
}
func (l genericResource) clone() *genericResource {
gi := *l.resourceFileInfo
rp := *l.resourcePathDescriptor
l.resourceFileInfo = &gi
l.resourcePathDescriptor = &rp
l.resourceContent = &resourceContent{}
return &l
}
// returns an opened file or nil if nothing to write (it may already be published).
func (l *genericResource) openDestinationsForWriting() (w io.WriteCloser, err error) {
l.publishInit.Do(func() {
targetFilenames := l.getTargetFilenames()
var changedFilenames []string
// Fast path:
// This is a processed version of the original;
// check if it already existis at the destination.
for _, targetFilename := range targetFilenames {
if _, err := l.getSpec().BaseFs.PublishFs.Stat(targetFilename); err == nil {
continue
}
changedFilenames = append(changedFilenames, targetFilename)
}
if len(changedFilenames) == 0 {
return
}
w, err = helpers.OpenFilesForWriting(l.getSpec().BaseFs.PublishFs, changedFilenames...)
})
return
}
func (r *genericResource) openPublishFileForWriting(relTargetPath string) (io.WriteCloser, error) {
return helpers.OpenFilesForWriting(r.spec.BaseFs.PublishFs, r.relTargetPathsFor(relTargetPath)...)
}
func (l *genericResource) permalinkFor(target string) string {
return l.spec.PermalinkForBaseURL(l.relPermalinkForRel(target, true), l.spec.BaseURL.HostURL())
}
func (l *genericResource) relPermalinkFor(target string) string {
return l.relPermalinkForRel(target, false)
}
func (l *genericResource) relPermalinkForRel(rel string, isAbs bool) string {
return l.spec.PathSpec.URLizeFilename(l.relTargetPathForRel(rel, false, isAbs, true))
}
func (l *genericResource) relTargetPathForRel(rel string, addBaseTargetPath, isAbs, isURL bool) string {
if addBaseTargetPath && len(l.baseTargetPathDirs) > 1 {
panic("multiple baseTargetPathDirs")
}
var basePath string
if addBaseTargetPath && len(l.baseTargetPathDirs) > 0 {
basePath = l.baseTargetPathDirs[0]
}
return l.relTargetPathForRelAndBasePath(rel, basePath, isAbs, isURL)
}
func (l *genericResource) relTargetPathForRelAndBasePath(rel, basePath string, isAbs, isURL bool) string {
rel = l.createBasePath(rel, isURL)
if basePath != "" {
rel = path.Join(basePath, rel)
}
if l.baseOffset != "" {
rel = path.Join(l.baseOffset, rel)
}
if isURL {
bp := l.spec.PathSpec.GetBasePath(!isAbs)
if bp != "" {
rel = path.Join(bp, rel)
}
}
if len(rel) == 0 || rel[0] != '/' {
rel = "/" + rel
}
return rel
}
func (l *genericResource) relTargetPaths() []string {
return l.relTargetPathsForRel(l.TargetPath())
}
func (l *genericResource) relTargetPathsFor(target string) []string {
return l.relTargetPathsForRel(target)
}
func (l *genericResource) relTargetPathsForRel(rel string) []string {
if len(l.baseTargetPathDirs) == 0 {
return []string{l.relTargetPathForRelAndBasePath(rel, "", false, false)}
}
targetPaths := make([]string, len(l.baseTargetPathDirs))
for i, dir := range l.baseTargetPathDirs {
targetPaths[i] = l.relTargetPathForRelAndBasePath(rel, dir, false, false)
}
return targetPaths
}
func (l *genericResource) updateParams(params map[string]interface{}) {
if l.params == nil {
l.params = params
return
}
// Sets the params not already set
for k, v := range params {
if _, found := l.params[k]; !found {
l.params[k] = v
}
}
}
type targetPather interface {
TargetPath() string
}
type permalinker interface {
targetPather
permalinkFor(target string) string
relPermalinkFor(target string) string
relTargetPaths() []string
relTargetPathsFor(target string) []string
}
type resourceContent struct {
content string
contentInit sync.Once
publishInit sync.Once
}
type resourceFileInfo struct {
// Will be set if this resource is backed by something other than a file.
openReadSeekerCloser resource.OpenReadSeekCloser
// This may be set to tell us to look in another filesystem for this resource.
// We, by default, use the sourceFs filesystem in the spec below.
sourceFs afero.Fs
// Absolute filename to the source, including any content folder path.
// Note that this is absolute in relation to the filesystem it is stored in.
// It can be a base path filesystem, and then this filename will not match
// the path to the file on the real filesystem.
sourceFilename string
fi hugofs.FileMetaInfo
// A hash of the source content. Is only calculated in caching situations.
h *resourceHash
}
func (fi *resourceFileInfo) ReadSeekCloser() (hugio.ReadSeekCloser, error) {
if fi.openReadSeekerCloser != nil {
return fi.openReadSeekerCloser()
}
f, err := fi.getSourceFs().Open(fi.getSourceFilename())
if err != nil {
return nil, err
}
return f, nil
}
func (fi *resourceFileInfo) getFileInfo() hugofs.FileMetaInfo {
return fi.fi
}
func (fi *resourceFileInfo) getSourceFilename() string {
return fi.sourceFilename
}
func (fi *resourceFileInfo) setSourceFilename(s string) {
// Make sure it's always loaded by sourceFilename.
fi.openReadSeekerCloser = nil
fi.sourceFilename = s
}
func (fi *resourceFileInfo) getSourceFs() afero.Fs {
return fi.sourceFs
}
func (fi *resourceFileInfo) setSourceFs(fs afero.Fs) {
fi.sourceFs = fs
}
func (fi *resourceFileInfo) hash() (string, error) {
var err error
fi.h.init.Do(func() {
var hash string
var f hugio.ReadSeekCloser
f, err = fi.ReadSeekCloser()
if err != nil {
err = errors.Wrap(err, "failed to open source file")
return
}
defer f.Close()
hash, err = helpers.MD5FromFileFast(f)
if err != nil {
return
}
fi.h.value = hash
})
return fi.h.value, err
}
func (fi *resourceFileInfo) size() int {
if fi.fi == nil {
return 0
}
return int(fi.fi.Size())
}
type resourceHash struct {
value string
init sync.Once
}
type resourcePathDescriptor struct {
// The relative target directory and filename.
relTargetDirFile dirFile
// Callback used to construct a target path relative to its owner.
targetPathBuilder func() page.TargetPaths
// This will normally be the same as above, but this will only apply to publishing
// of resources. It may be mulltiple values when in multihost mode.
baseTargetPathDirs []string
// baseOffset is set when the output format's path has a offset, e.g. for AMP.
baseOffset string
}