hugo/tpl/images/images.go
2024-01-28 23:14:09 +01:00

119 lines
2.8 KiB
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 images provides template functions for manipulating images.
package images
import (
"errors"
"image"
"sync"
"github.com/bep/overlayfs"
"github.com/gohugoio/hugo/resources/images"
// Importing image codecs for image.DecodeConfig
_ "image/gif"
_ "image/jpeg"
_ "image/png"
// Import webp codec
_ "golang.org/x/image/webp"
"github.com/gohugoio/hugo/deps"
"github.com/spf13/afero"
"github.com/spf13/cast"
)
// New returns a new instance of the images-namespaced template functions.
func New(d *deps.Deps) *Namespace {
var readFileFs afero.Fs
// The docshelper script does not have or need all the dependencies set up.
if d.PathSpec != nil {
readFileFs = overlayfs.New(overlayfs.Options{
Fss: []afero.Fs{
d.PathSpec.BaseFs.Work,
d.PathSpec.BaseFs.Content.Fs,
},
})
}
return &Namespace{
readFileFs: readFileFs,
Filters: &images.Filters{},
cache: map[string]image.Config{},
deps: d,
}
}
// Namespace provides template functions for the "images" namespace.
type Namespace struct {
*images.Filters
readFileFs afero.Fs
cacheMu sync.RWMutex
cache map[string]image.Config
deps *deps.Deps
}
// Config returns the image.Config for the specified path relative to the
// working directory.
func (ns *Namespace) Config(path any) (image.Config, error) {
filename, err := cast.ToStringE(path)
if err != nil {
return image.Config{}, err
}
if filename == "" {
return image.Config{}, errors.New("config needs a filename")
}
// Check cache for image config.
ns.cacheMu.RLock()
config, ok := ns.cache[filename]
ns.cacheMu.RUnlock()
if ok {
return config, nil
}
f, err := ns.readFileFs.Open(filename)
if err != nil {
return image.Config{}, err
}
defer f.Close()
config, _, err = image.DecodeConfig(f)
if err != nil {
return config, err
}
ns.cacheMu.Lock()
ns.cache[filename] = config
ns.cacheMu.Unlock()
return config, nil
}
// Filter applies the given filters to the image given as the last element in args.
func (ns *Namespace) Filter(args ...any) (images.ImageResource, error) {
if len(args) < 2 {
return nil, errors.New("must provide an image and one or more filters")
}
img := args[len(args)-1].(images.ImageResource)
filtersv := args[:len(args)-1]
return img.Filter(filtersv...)
}