hugo/resources/page/pages_cache.go
Bjørn Erik Pedersen 597e418cb0
Make Page an interface
The main motivation of this commit is to add a `page.Page` interface to replace the very file-oriented `hugolib.Page` struct.
This is all a preparation step for issue  #5074, "pages from other data sources".

But this also fixes a set of annoying limitations, especially related to custom output formats, and shortcodes.

Most notable changes:

* The inner content of shortcodes using the `{{%` as the outer-most delimiter will now be sent to the content renderer, e.g. Blackfriday.
  This means that any markdown will partake in the global ToC and footnote context etc.
* The Custom Output formats are now "fully virtualized". This removes many of the current limitations.
* The taxonomy list type now has a reference to the `Page` object.
  This improves the taxonomy template `.Title` situation and make common template constructs much simpler.

See #5074
Fixes #5763
Fixes #5758
Fixes #5090
Fixes #5204
Fixes #4695
Fixes #5607
Fixes #5707
Fixes #5719
Fixes #3113
Fixes #5706
Fixes #5767
Fixes #5723
Fixes #5769
Fixes #5770
Fixes #5771
Fixes #5759
Fixes #5776
Fixes #5777
Fixes #5778
2019-03-23 18:51:22 +01:00

136 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 page
import (
"sync"
)
type pageCacheEntry struct {
in []Pages
out Pages
}
func (entry pageCacheEntry) matches(pageLists []Pages) bool {
if len(entry.in) != len(pageLists) {
return false
}
for i, p := range pageLists {
if !pagesEqual(p, entry.in[i]) {
return false
}
}
return true
}
type pageCache struct {
sync.RWMutex
m map[string][]pageCacheEntry
}
func newPageCache() *pageCache {
return &pageCache{m: make(map[string][]pageCacheEntry)}
}
func (c *pageCache) clear() {
c.Lock()
defer c.Unlock()
c.m = make(map[string][]pageCacheEntry)
}
// get/getP gets a Pages slice from the cache matching the given key and
// all the provided Pages slices.
// If none found in cache, a copy of the first slice is created.
//
// If an apply func is provided, that func is applied to the newly created copy.
//
// The getP variant' apply func takes a pointer to Pages.
//
// The cache and the execution of the apply func is protected by a RWMutex.
func (c *pageCache) get(key string, apply func(p Pages), pageLists ...Pages) (Pages, bool) {
return c.getP(key, func(p *Pages) {
if apply != nil {
apply(*p)
}
}, pageLists...)
}
func (c *pageCache) getP(key string, apply func(p *Pages), pageLists ...Pages) (Pages, bool) {
c.RLock()
if cached, ok := c.m[key]; ok {
for _, entry := range cached {
if entry.matches(pageLists) {
c.RUnlock()
return entry.out, true
}
}
}
c.RUnlock()
c.Lock()
defer c.Unlock()
// double-check
if cached, ok := c.m[key]; ok {
for _, entry := range cached {
if entry.matches(pageLists) {
return entry.out, true
}
}
}
p := pageLists[0]
pagesCopy := append(Pages(nil), p...)
if apply != nil {
apply(&pagesCopy)
}
entry := pageCacheEntry{in: pageLists, out: pagesCopy}
if v, ok := c.m[key]; ok {
c.m[key] = append(v, entry)
} else {
c.m[key] = []pageCacheEntry{entry}
}
return pagesCopy, false
}
// pagesEqual returns whether p1 and p2 are equal.
func pagesEqual(p1, p2 Pages) bool {
if p1 == nil && p2 == nil {
return true
}
if p1 == nil || p2 == nil {
return false
}
if p1.Len() != p2.Len() {
return false
}
if p1.Len() == 0 {
return true
}
for i := 0; i < len(p1); i++ {
if p1[i] != p2[i] {
return false
}
}
return true
}