hugo/tpl/resources/resources.go
Bjørn Erik Pedersen ce524d0b5e Add a page template func
Fixes #9339
2023-02-25 19:53:18 +01:00

436 lines
12 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 resources provides template functions for working with resources.
package resources
import (
"context"
"fmt"
"sync"
"errors"
"github.com/gohugoio/hugo/common/maps"
"github.com/gohugoio/hugo/tpl/internal/resourcehelpers"
"github.com/gohugoio/hugo/helpers"
"github.com/gohugoio/hugo/resources/postpub"
"github.com/gohugoio/hugo/deps"
"github.com/gohugoio/hugo/resources"
"github.com/gohugoio/hugo/resources/resource"
"github.com/gohugoio/hugo/resources/resource_factories/bundler"
"github.com/gohugoio/hugo/resources/resource_factories/create"
"github.com/gohugoio/hugo/resources/resource_transformers/babel"
"github.com/gohugoio/hugo/resources/resource_transformers/integrity"
"github.com/gohugoio/hugo/resources/resource_transformers/minifier"
"github.com/gohugoio/hugo/resources/resource_transformers/postcss"
"github.com/gohugoio/hugo/resources/resource_transformers/templates"
"github.com/gohugoio/hugo/resources/resource_transformers/tocss/dartsass"
"github.com/gohugoio/hugo/resources/resource_transformers/tocss/scss"
"github.com/spf13/cast"
)
// New returns a new instance of the resources-namespaced template functions.
func New(deps *deps.Deps) (*Namespace, error) {
if deps.ResourceSpec == nil {
return &Namespace{}, nil
}
scssClient, err := scss.New(deps.BaseFs.Assets, deps.ResourceSpec)
if err != nil {
return nil, err
}
minifyClient, err := minifier.New(deps.ResourceSpec)
if err != nil {
return nil, err
}
return &Namespace{
deps: deps,
scssClientLibSass: scssClient,
createClient: create.New(deps.ResourceSpec),
bundlerClient: bundler.New(deps.ResourceSpec),
integrityClient: integrity.New(deps.ResourceSpec),
minifyClient: minifyClient,
postcssClient: postcss.New(deps.ResourceSpec),
templatesClient: templates.New(deps.ResourceSpec, deps),
babelClient: babel.New(deps.ResourceSpec),
}, nil
}
var _ resource.ResourceFinder = (*Namespace)(nil)
// Namespace provides template functions for the "resources" namespace.
type Namespace struct {
deps *deps.Deps
createClient *create.Client
bundlerClient *bundler.Client
scssClientLibSass *scss.Client
integrityClient *integrity.Client
minifyClient *minifier.Client
postcssClient *postcss.Client
babelClient *babel.Client
templatesClient *templates.Client
// The Dart Client requires a os/exec process, so only
// create it if we really need it.
// This is mostly to avoid creating one per site build test.
scssClientDartSassInit sync.Once
scssClientDartSass *dartsass.Client
}
func (ns *Namespace) getscssClientDartSass() (*dartsass.Client, error) {
var err error
ns.scssClientDartSassInit.Do(func() {
ns.scssClientDartSass, err = dartsass.New(ns.deps.BaseFs.Assets, ns.deps.ResourceSpec)
if err != nil {
return
}
ns.deps.BuildClosers.Add(ns.scssClientDartSass)
})
return ns.scssClientDartSass, err
}
// Copy copies r to the new targetPath in s.
func (ns *Namespace) Copy(s any, r resource.Resource) (resource.Resource, error) {
targetPath, err := cast.ToStringE(s)
if err != nil {
panic(err)
}
return ns.createClient.Copy(r, targetPath)
}
// Get locates the filename given in Hugo's assets filesystem
// and creates a Resource object that can be used for further transformations.
func (ns *Namespace) Get(filename any) resource.Resource {
filenamestr, err := cast.ToStringE(filename)
if err != nil {
panic(err)
}
if filenamestr == "" {
return nil
}
r, err := ns.createClient.Get(filenamestr)
if err != nil {
panic(err)
}
return r
}
// GetRemote gets the URL (via HTTP(s)) in the first argument in args and creates Resource object that can be used for
// further transformations.
//
// A second argument may be provided with an option map.
//
// Note: This method does not return any error as a second argument,
// for any error situations the error can be checked in .Err.
func (ns *Namespace) GetRemote(args ...any) resource.Resource {
get := func(args ...any) (resource.Resource, error) {
if len(args) < 1 {
return nil, errors.New("must provide an URL")
}
urlstr, err := cast.ToStringE(args[0])
if err != nil {
return nil, err
}
var options map[string]any
if len(args) > 1 {
options, err = maps.ToStringMapE(args[1])
if err != nil {
return nil, err
}
}
return ns.createClient.FromRemote(urlstr, options)
}
r, err := get(args...)
if err != nil {
switch v := err.(type) {
case *create.HTTPError:
return resources.NewErrorResource(resource.NewResourceError(v, v.Data))
default:
return resources.NewErrorResource(resource.NewResourceError(fmt.Errorf("error calling resources.GetRemote: %w", err), make(map[string]any)))
}
}
return r
}
// GetMatch finds the first Resource matching the given pattern, or nil if none found.
//
// It looks for files in the assets file system.
//
// See Match for a more complete explanation about the rules used.
func (ns *Namespace) GetMatch(pattern any) resource.Resource {
patternStr, err := cast.ToStringE(pattern)
if err != nil {
panic(err)
}
r, err := ns.createClient.GetMatch(patternStr)
if err != nil {
panic(err)
}
return r
}
// ByType returns resources of a given resource type (e.g. "image").
func (ns *Namespace) ByType(typ any) resource.Resources {
return ns.createClient.ByType(cast.ToString(typ))
}
// Match gets all resources matching the given base path prefix, e.g
// "*.png" will match all png files. The "*" does not match path delimiters (/),
// so if you organize your resources in sub-folders, you need to be explicit about it, e.g.:
// "images/*.png". To match any PNG image anywhere in the bundle you can do "**.png", and
// to match all PNG images below the images folder, use "images/**.jpg".
//
// The matching is case insensitive.
//
// Match matches by using the files name with path relative to the file system root
// with Unix style slashes (/) and no leading slash, e.g. "images/logo.png".
//
// See https://github.com/gobwas/glob for the full rules set.
//
// It looks for files in the assets file system.
//
// See Match for a more complete explanation about the rules used.
func (ns *Namespace) Match(pattern any) resource.Resources {
patternStr, err := cast.ToStringE(pattern)
if err != nil {
panic(err)
}
r, err := ns.createClient.Match(patternStr)
if err != nil {
panic(err)
}
return r
}
// Concat concatenates a slice of Resource objects. These resources must
// (currently) be of the same Media Type.
func (ns *Namespace) Concat(targetPathIn any, r any) (resource.Resource, error) {
targetPath, err := cast.ToStringE(targetPathIn)
if err != nil {
return nil, err
}
var rr resource.Resources
switch v := r.(type) {
case resource.Resources:
rr = v
case resource.ResourcesConverter:
rr = v.ToResources()
default:
return nil, fmt.Errorf("slice %T not supported in concat", r)
}
if len(rr) == 0 {
return nil, errors.New("must provide one or more Resource objects to concat")
}
return ns.bundlerClient.Concat(targetPath, rr)
}
// FromString creates a Resource from a string published to the relative target path.
func (ns *Namespace) FromString(targetPathIn, contentIn any) (resource.Resource, error) {
targetPath, err := cast.ToStringE(targetPathIn)
if err != nil {
return nil, err
}
content, err := cast.ToStringE(contentIn)
if err != nil {
return nil, err
}
return ns.createClient.FromString(targetPath, content)
}
// ExecuteAsTemplate creates a Resource from a Go template, parsed and executed with
// the given data, and published to the relative target path.
func (ns *Namespace) ExecuteAsTemplate(ctx context.Context, args ...any) (resource.Resource, error) {
if len(args) != 3 {
return nil, fmt.Errorf("must provide targetPath, the template data context and a Resource object")
}
targetPath, err := cast.ToStringE(args[0])
if err != nil {
return nil, err
}
data := args[1]
r, ok := args[2].(resources.ResourceTransformer)
if !ok {
return nil, fmt.Errorf("type %T not supported in Resource transformations", args[2])
}
return ns.templatesClient.ExecuteAsTemplate(ctx, r, targetPath, data)
}
// Fingerprint transforms the given Resource with a MD5 hash of the content in
// the RelPermalink and Permalink.
func (ns *Namespace) Fingerprint(args ...any) (resource.Resource, error) {
if len(args) < 1 || len(args) > 2 {
return nil, errors.New("must provide a Resource and (optional) crypto algo")
}
var algo string
resIdx := 0
if len(args) == 2 {
resIdx = 1
var err error
algo, err = cast.ToStringE(args[0])
if err != nil {
return nil, err
}
}
r, ok := args[resIdx].(resources.ResourceTransformer)
if !ok {
return nil, fmt.Errorf("%T can not be transformed", args[resIdx])
}
return ns.integrityClient.Fingerprint(r, algo)
}
// Minify minifies the given Resource using the MediaType to pick the correct
// minifier.
func (ns *Namespace) Minify(r resources.ResourceTransformer) (resource.Resource, error) {
return ns.minifyClient.Minify(r)
}
// ToCSS converts the given Resource to CSS. You can optional provide an Options
// object or a target path (string) as first argument.
func (ns *Namespace) ToCSS(args ...any) (resource.Resource, error) {
const (
// Transpiler implementation can be controlled from the client by
// setting the 'transpiler' option.
// Default is currently 'libsass', but that may change.
transpilerDart = "dartsass"
transpilerLibSass = "libsass"
)
var (
r resources.ResourceTransformer
m map[string]any
targetPath string
err error
ok bool
transpiler = transpilerLibSass
)
r, targetPath, ok = resourcehelpers.ResolveIfFirstArgIsString(args)
if !ok {
r, m, err = resourcehelpers.ResolveArgs(args)
if err != nil {
return nil, err
}
}
if m != nil {
if t, found := maps.LookupEqualFold(m, "transpiler"); found {
switch t {
case transpilerDart, transpilerLibSass:
transpiler = cast.ToString(t)
default:
return nil, fmt.Errorf("unsupported transpiler %q; valid values are %q or %q", t, transpilerLibSass, transpilerDart)
}
}
}
if transpiler == transpilerLibSass {
var options scss.Options
if targetPath != "" {
options.TargetPath = helpers.ToSlashTrimLeading(targetPath)
} else if m != nil {
options, err = scss.DecodeOptions(m)
if err != nil {
return nil, err
}
}
return ns.scssClientLibSass.ToCSS(r, options)
}
if m == nil {
m = make(map[string]any)
}
if targetPath != "" {
m["targetPath"] = targetPath
}
client, err := ns.getscssClientDartSass()
if err != nil {
return nil, err
}
return client.ToCSS(r, m)
}
// PostCSS processes the given Resource with PostCSS
func (ns *Namespace) PostCSS(args ...any) (resource.Resource, error) {
r, m, err := resourcehelpers.ResolveArgs(args)
if err != nil {
return nil, err
}
return ns.postcssClient.Process(r, m)
}
// PostProcess processes r after the build.
func (ns *Namespace) PostProcess(r resource.Resource) (postpub.PostPublishedResource, error) {
return ns.deps.ResourceSpec.PostProcess(r)
}
// Babel processes the given Resource with Babel.
func (ns *Namespace) Babel(args ...any) (resource.Resource, error) {
r, m, err := resourcehelpers.ResolveArgs(args)
if err != nil {
return nil, err
}
var options babel.Options
if m != nil {
options, err = babel.DecodeOptions(m)
if err != nil {
return nil, err
}
}
return ns.babelClient.Process(r, options)
}