hugo/output/layout.go
Bjørn Erik Pedersen 9f5a92078a
Add Hugo Modules
This commit implements Hugo Modules.

This is a broad subject, but some keywords include:

* A new `module` configuration section where you can import almost anything. You can configure both your own file mounts nd the file mounts of the modules you import. This is the new recommended way of configuring what you earlier put in `configDir`, `staticDir` etc. And it also allows you to mount folders in non-Hugo-projects, e.g. the `SCSS` folder in the Bootstrap GitHub project.
* A module consists of a set of mounts to the standard 7 component types in Hugo: `static`, `content`, `layouts`, `data`, `assets`, `i18n`, and `archetypes`. Yes, Theme Components can now include content, which should be very useful, especially in bigger multilingual projects.
* Modules not in your local file cache will be downloaded automatically and even "hot replaced" while the server is running.
* Hugo Modules supports and encourages semver versioned modules, and uses the minimal version selection algorithm to resolve versions.
* A new set of CLI commands are provided to manage all of this: `hugo mod init`,  `hugo mod get`,  `hugo mod graph`,  `hugo mod tidy`, and  `hugo mod vendor`.

All of the above is backed by Go Modules.

Fixes #5973
Fixes #5996
Fixes #6010
Fixes #5911
Fixes #5940
Fixes #6074
Fixes #6082
Fixes #6092
2019-07-24 09:35:53 +02:00

272 lines
6 KiB
Go

// Copyright 2017-present 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 output
import (
"fmt"
"strings"
"sync"
"github.com/gohugoio/hugo/helpers"
)
// These may be used as content sections with potential conflicts. Avoid that.
var reservedSections = map[string]bool{
"shortcodes": true,
"partials": true,
}
// LayoutDescriptor describes how a layout should be chosen. This is
// typically built from a Page.
type LayoutDescriptor struct {
Type string
Section string
Kind string
Lang string
Layout string
// LayoutOverride indicates what we should only look for the above layout.
LayoutOverride bool
}
// LayoutHandler calculates the layout template to use to render a given output type.
type LayoutHandler struct {
mu sync.RWMutex
cache map[layoutCacheKey][]string
}
type layoutCacheKey struct {
d LayoutDescriptor
f string
}
// NewLayoutHandler creates a new LayoutHandler.
func NewLayoutHandler() *LayoutHandler {
return &LayoutHandler{cache: make(map[layoutCacheKey][]string)}
}
// For returns a layout for the given LayoutDescriptor and options.
// Layouts are rendered and cached internally.
func (l *LayoutHandler) For(d LayoutDescriptor, f Format) ([]string, error) {
// We will get lots of requests for the same layouts, so avoid recalculations.
key := layoutCacheKey{d, f.Name}
l.mu.RLock()
if cacheVal, found := l.cache[key]; found {
l.mu.RUnlock()
return cacheVal, nil
}
l.mu.RUnlock()
layouts := resolvePageTemplate(d, f)
layouts = prependTextPrefixIfNeeded(f, layouts...)
layouts = helpers.UniqueStringsReuse(layouts)
l.mu.Lock()
l.cache[key] = layouts
l.mu.Unlock()
return layouts, nil
}
type layoutBuilder struct {
layoutVariations []string
typeVariations []string
d LayoutDescriptor
f Format
}
func (l *layoutBuilder) addLayoutVariations(vars ...string) {
for _, layoutVar := range vars {
if l.d.LayoutOverride && layoutVar != l.d.Layout {
continue
}
l.layoutVariations = append(l.layoutVariations, layoutVar)
}
}
func (l *layoutBuilder) addTypeVariations(vars ...string) {
for _, typeVar := range vars {
if !reservedSections[typeVar] {
l.typeVariations = append(l.typeVariations, typeVar)
}
}
}
func (l *layoutBuilder) addSectionType() {
if l.d.Section != "" {
l.addTypeVariations(l.d.Section)
}
}
func (l *layoutBuilder) addKind() {
l.addLayoutVariations(l.d.Kind)
l.addTypeVariations(l.d.Kind)
}
func resolvePageTemplate(d LayoutDescriptor, f Format) []string {
b := &layoutBuilder{d: d, f: f}
if d.Layout != "" {
b.addLayoutVariations(d.Layout)
}
if d.Type != "" {
b.addTypeVariations(d.Type)
}
switch d.Kind {
case "page":
b.addLayoutVariations("single")
b.addSectionType()
case "home":
b.addLayoutVariations("index", "home")
// Also look in the root
b.addTypeVariations("")
case "section":
if d.Section != "" {
b.addLayoutVariations(d.Section)
}
b.addSectionType()
b.addKind()
case "taxonomy":
if d.Section != "" {
b.addLayoutVariations(d.Section)
}
b.addKind()
b.addSectionType()
case "taxonomyTerm":
if d.Section != "" {
b.addLayoutVariations(d.Section + ".terms")
}
b.addTypeVariations("taxonomy")
b.addSectionType()
b.addLayoutVariations("terms")
}
isRSS := f.Name == RSSFormat.Name
if isRSS {
// The historic and common rss.xml case
b.addLayoutVariations("")
}
// All have _default in their lookup path
b.addTypeVariations("_default")
if d.Kind != "page" {
// Add the common list type
b.addLayoutVariations("list")
}
layouts := b.resolveVariations()
if isRSS {
layouts = append(layouts, "_internal/_default/rss.xml")
}
return layouts
}
func (l *layoutBuilder) resolveVariations() []string {
var layouts []string
var variations []string
name := strings.ToLower(l.f.Name)
if l.d.Lang != "" {
// We prefer the most specific type before language.
variations = append(variations, []string{fmt.Sprintf("%s.%s", l.d.Lang, name), name, l.d.Lang}...)
} else {
variations = append(variations, name)
}
variations = append(variations, "")
for _, typeVar := range l.typeVariations {
for _, variation := range variations {
for _, layoutVar := range l.layoutVariations {
if variation == "" && layoutVar == "" {
continue
}
template := layoutTemplate(typeVar, layoutVar)
layouts = append(layouts, replaceKeyValues(template,
"TYPE", typeVar,
"LAYOUT", layoutVar,
"VARIATIONS", variation,
"EXTENSION", l.f.MediaType.Suffix(),
))
}
}
}
return filterDotLess(layouts)
}
func layoutTemplate(typeVar, layoutVar string) string {
var l string
if typeVar != "" {
l = "TYPE/"
}
if layoutVar != "" {
l += "LAYOUT.VARIATIONS.EXTENSION"
} else {
l += "VARIATIONS.EXTENSION"
}
return l
}
func filterDotLess(layouts []string) []string {
var filteredLayouts []string
for _, l := range layouts {
l = strings.Replace(l, "..", ".", -1)
l = strings.Trim(l, ".")
// If media type has no suffix, we have "index" type of layouts in this list, which
// doesn't make much sense.
if strings.Contains(l, ".") {
filteredLayouts = append(filteredLayouts, l)
}
}
return filteredLayouts
}
func prependTextPrefixIfNeeded(f Format, layouts ...string) []string {
if !f.IsPlainText {
return layouts
}
newLayouts := make([]string, len(layouts))
for i, l := range layouts {
newLayouts[i] = "_text/" + l
}
return newLayouts
}
func replaceKeyValues(s string, oldNew ...string) string {
replacer := strings.NewReplacer(oldNew...)
return replacer.Replace(s)
}