hugo/output/layout.go
Bjørn Erik Pedersen c6d650c8c8
tpl/tplimpl: Rework template management to get rid of concurrency issues
This more or less completes the simplification of the template handling code in Hugo started in v0.62.

The main motivation was to fix a long lasting issue about a crash in HTML content files  without front matter.

But this commit also comes with a big functional improvement.

As we now have moved the base template evaluation to the build stage we now use the same lookup rules for `baseof` as for `list` etc. type of templates.

This means that in this simple example you can have a `baseof` template for the `blog` section without having to duplicate the others:

```
layouts
├── _default
│   ├── baseof.html
│   ├── list.html
│   └── single.html
└── blog
    └── baseof.html
```

Also, when simplifying code, you often get rid of some double work, as shown in the "site building" benchmarks below.

These benchmarks looks suspiciously good, but I have repeated the below with ca. the same result. Compared to master:

```
name                              old time/op    new time/op    delta
SiteNew/Bundle_with_image-16        13.1ms ± 1%    10.5ms ± 1%  -19.34%  (p=0.029 n=4+4)
SiteNew/Bundle_with_JSON_file-16    13.0ms ± 0%    10.7ms ± 1%  -18.05%  (p=0.029 n=4+4)
SiteNew/Tags_and_categories-16      46.4ms ± 2%    43.1ms ± 1%   -7.15%  (p=0.029 n=4+4)
SiteNew/Canonify_URLs-16            52.2ms ± 2%    47.8ms ± 1%   -8.30%  (p=0.029 n=4+4)
SiteNew/Deep_content_tree-16        77.9ms ± 1%    70.9ms ± 1%   -9.01%  (p=0.029 n=4+4)
SiteNew/Many_HTML_templates-16      43.0ms ± 0%    37.2ms ± 1%  -13.54%  (p=0.029 n=4+4)
SiteNew/Page_collections-16         58.2ms ± 1%    52.4ms ± 1%   -9.95%  (p=0.029 n=4+4)

name                              old alloc/op   new alloc/op   delta
SiteNew/Bundle_with_image-16        3.81MB ± 0%    2.22MB ± 0%  -41.70%  (p=0.029 n=4+4)
SiteNew/Bundle_with_JSON_file-16    3.60MB ± 0%    2.01MB ± 0%  -44.20%  (p=0.029 n=4+4)
SiteNew/Tags_and_categories-16      19.3MB ± 1%    14.1MB ± 0%  -26.91%  (p=0.029 n=4+4)
SiteNew/Canonify_URLs-16            70.7MB ± 0%    69.0MB ± 0%   -2.40%  (p=0.029 n=4+4)
SiteNew/Deep_content_tree-16        37.1MB ± 0%    31.2MB ± 0%  -15.94%  (p=0.029 n=4+4)
SiteNew/Many_HTML_templates-16      17.6MB ± 0%    10.6MB ± 0%  -39.92%  (p=0.029 n=4+4)
SiteNew/Page_collections-16         25.9MB ± 0%    21.2MB ± 0%  -17.99%  (p=0.029 n=4+4)

name                              old allocs/op  new allocs/op  delta
SiteNew/Bundle_with_image-16         52.3k ± 0%     26.1k ± 0%  -50.18%  (p=0.029 n=4+4)
SiteNew/Bundle_with_JSON_file-16     52.3k ± 0%     26.1k ± 0%  -50.16%  (p=0.029 n=4+4)
SiteNew/Tags_and_categories-16        336k ± 1%      269k ± 0%  -19.90%  (p=0.029 n=4+4)
SiteNew/Canonify_URLs-16              422k ± 0%      395k ± 0%   -6.43%  (p=0.029 n=4+4)
SiteNew/Deep_content_tree-16          401k ± 0%      313k ± 0%  -21.79%  (p=0.029 n=4+4)
SiteNew/Many_HTML_templates-16        247k ± 0%      143k ± 0%  -42.17%  (p=0.029 n=4+4)
SiteNew/Page_collections-16           282k ± 0%      207k ± 0%  -26.55%  (p=0.029 n=4+4)
```

Fixes #6716
Fixes #6760
Fixes #6768
Fixes #6778
2020-01-22 09:39:49 +01:00

280 lines
6.3 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
RenderingHook bool
Baseof bool
}
func (d LayoutDescriptor) isList() bool {
return !d.RenderingHook && d.Kind != "page"
}
// 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 = 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.Baseof && layoutVar != "baseof" {
l.layoutVariations = append(l.layoutVariations, layoutVar+"-baseof")
continue
}
if !l.d.RenderingHook && !l.d.Baseof && 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] {
if l.d.RenderingHook {
typeVar = typeVar + renderingHookRoot
}
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)
}
const renderingHookRoot = "/_markup"
func resolvePageTemplate(d LayoutDescriptor, f Format) []string {
b := &layoutBuilder{d: d, f: f}
if d.RenderingHook {
b.addLayoutVariations(d.Kind)
} else {
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 !d.RenderingHook && !d.Baseof && isRSS {
// The historic and common rss.xml case
b.addLayoutVariations("")
}
// All have _default in their lookup path
b.addTypeVariations("_default")
if d.isList() {
// Add the common list type
b.addLayoutVariations("list")
}
if d.Baseof {
b.addLayoutVariations("baseof")
}
layouts := b.resolveVariations()
if !d.RenderingHook && !d.Baseof && 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 replaceKeyValues(s string, oldNew ...string) string {
replacer := strings.NewReplacer(oldNew...)
return replacer.Replace(s)
}