hugo/hugolib/taxonomy.go
Bjørn Erik Pedersen 7ff0a8ee9f Simplify page tree logic
This is preparation for #6041.

For historic reasons, the code for bulding the section tree and the taxonomies were very much separate.

This works, but makes it hard to extend, maintain, and possibly not so fast as it could be.

This simplification also introduces 3 slightly breaking changes, which I suspect most people will be pleased about. See referenced issues:

This commit also switches the radix tree dependency to a mutable implementation: github.com/armon/go-radix.

Fixes #6154
Fixes #6153
Fixes #6152
2019-08-08 20:13:39 +02:00

156 lines
4.3 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 hugolib
import (
"fmt"
"sort"
"github.com/gohugoio/hugo/compare"
"github.com/gohugoio/hugo/resources/page"
)
// The TaxonomyList is a list of all taxonomies and their values
// e.g. List['tags'] => TagTaxonomy (from above)
type TaxonomyList map[string]Taxonomy
func (tl TaxonomyList) String() string {
return fmt.Sprintf("TaxonomyList(%d)", len(tl))
}
// A Taxonomy is a map of keywords to a list of pages.
// For example
// TagTaxonomy['technology'] = page.WeightedPages
// TagTaxonomy['go'] = page.WeightedPages
type Taxonomy map[string]page.WeightedPages
// OrderedTaxonomy is another representation of an Taxonomy using an array rather than a map.
// Important because you can't order a map.
type OrderedTaxonomy []OrderedTaxonomyEntry
// OrderedTaxonomyEntry is similar to an element of a Taxonomy, but with the key embedded (as name)
// e.g: {Name: Technology, page.WeightedPages: TaxonomyPages}
type OrderedTaxonomyEntry struct {
Name string
page.WeightedPages
}
// Get the weighted pages for the given key.
func (i Taxonomy) Get(key string) page.WeightedPages {
return i[key]
}
// Count the weighted pages for the given key.
func (i Taxonomy) Count(key string) int { return len(i[key]) }
func (i Taxonomy) add(key string, w page.WeightedPage) {
i[key] = append(i[key], w)
}
// TaxonomyArray returns an ordered taxonomy with a non defined order.
func (i Taxonomy) TaxonomyArray() OrderedTaxonomy {
ies := make([]OrderedTaxonomyEntry, len(i))
count := 0
for k, v := range i {
ies[count] = OrderedTaxonomyEntry{Name: k, WeightedPages: v}
count++
}
return ies
}
// Alphabetical returns an ordered taxonomy sorted by key name.
func (i Taxonomy) Alphabetical() OrderedTaxonomy {
name := func(i1, i2 *OrderedTaxonomyEntry) bool {
return compare.LessStrings(i1.Name, i2.Name)
}
ia := i.TaxonomyArray()
oiBy(name).Sort(ia)
return ia
}
// ByCount returns an ordered taxonomy sorted by # of pages per key.
// If taxonomies have the same # of pages, sort them alphabetical
func (i Taxonomy) ByCount() OrderedTaxonomy {
count := func(i1, i2 *OrderedTaxonomyEntry) bool {
li1 := len(i1.WeightedPages)
li2 := len(i2.WeightedPages)
if li1 == li2 {
return compare.LessStrings(i1.Name, i2.Name)
}
return li1 > li2
}
ia := i.TaxonomyArray()
oiBy(count).Sort(ia)
return ia
}
// Pages returns the Pages for this taxonomy.
func (ie OrderedTaxonomyEntry) Pages() page.Pages {
return ie.WeightedPages.Pages()
}
// Count returns the count the pages in this taxonomy.
func (ie OrderedTaxonomyEntry) Count() int {
return len(ie.WeightedPages)
}
// Term returns the name given to this taxonomy.
func (ie OrderedTaxonomyEntry) Term() string {
return ie.Name
}
// Reverse reverses the order of the entries in this taxonomy.
func (t OrderedTaxonomy) Reverse() OrderedTaxonomy {
for i, j := 0, len(t)-1; i < j; i, j = i+1, j-1 {
t[i], t[j] = t[j], t[i]
}
return t
}
// A type to implement the sort interface for TaxonomyEntries.
type orderedTaxonomySorter struct {
taxonomy OrderedTaxonomy
by oiBy
}
// Closure used in the Sort.Less method.
type oiBy func(i1, i2 *OrderedTaxonomyEntry) bool
func (by oiBy) Sort(taxonomy OrderedTaxonomy) {
ps := &orderedTaxonomySorter{
taxonomy: taxonomy,
by: by, // The Sort method's receiver is the function (closure) that defines the sort order.
}
sort.Stable(ps)
}
// Len is part of sort.Interface.
func (s *orderedTaxonomySorter) Len() int {
return len(s.taxonomy)
}
// Swap is part of sort.Interface.
func (s *orderedTaxonomySorter) Swap(i, j int) {
s.taxonomy[i], s.taxonomy[j] = s.taxonomy[j], s.taxonomy[i]
}
// Less is part of sort.Interface. It is implemented by calling the "by" closure in the sorter.
func (s *orderedTaxonomySorter) Less(i, j int) bool {
return s.by(&s.taxonomy[i], &s.taxonomy[j])
}