hugo/hugolib/shortcode.go
Bjørn Erik Pedersen 8adba648cc all: Remove unused code
Using x/tools/cmd/deadcode
2023-12-18 19:51:26 +01:00

738 lines
20 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 (
"bytes"
"context"
"errors"
"fmt"
"html/template"
"path"
"reflect"
"regexp"
"sort"
"strconv"
"strings"
"sync"
"github.com/gohugoio/hugo/common/herrors"
"github.com/gohugoio/hugo/parser/pageparser"
"github.com/gohugoio/hugo/resources/page"
"github.com/gohugoio/hugo/common/maps"
"github.com/gohugoio/hugo/common/text"
"github.com/gohugoio/hugo/common/urls"
"github.com/gohugoio/hugo/output"
bp "github.com/gohugoio/hugo/bufferpool"
"github.com/gohugoio/hugo/tpl"
)
var (
_ urls.RefLinker = (*ShortcodeWithPage)(nil)
_ pageWrapper = (*ShortcodeWithPage)(nil)
_ text.Positioner = (*ShortcodeWithPage)(nil)
)
// ShortcodeWithPage is the "." context in a shortcode template.
type ShortcodeWithPage struct {
Params any
Inner template.HTML
Page page.Page
Parent *ShortcodeWithPage
Name string
IsNamedParams bool
// Zero-based ordinal in relation to its parent. If the parent is the page itself,
// this ordinal will represent the position of this shortcode in the page content.
Ordinal int
// Indentation before the opening shortcode in the source.
indentation string
innerDeindentInit sync.Once
innerDeindent template.HTML
// pos is the position in bytes in the source file. Used for error logging.
posInit sync.Once
posOffset int
pos text.Position
scratch *maps.Scratch
}
// InnerDeindent returns the (potentially de-indented) inner content of the shortcode.
func (scp *ShortcodeWithPage) InnerDeindent() template.HTML {
if scp.indentation == "" {
return scp.Inner
}
scp.innerDeindentInit.Do(func() {
b := bp.GetBuffer()
text.VisitLinesAfter(string(scp.Inner), func(s string) {
if strings.HasPrefix(s, scp.indentation) {
b.WriteString(strings.TrimPrefix(s, scp.indentation))
} else {
b.WriteString(s)
}
})
scp.innerDeindent = template.HTML(b.String())
bp.PutBuffer(b)
})
return scp.innerDeindent
}
// Position returns this shortcode's detailed position. Note that this information
// may be expensive to calculate, so only use this in error situations.
func (scp *ShortcodeWithPage) Position() text.Position {
scp.posInit.Do(func() {
if p, ok := mustUnwrapPage(scp.Page).(pageContext); ok {
scp.pos = p.posOffset(scp.posOffset)
}
})
return scp.pos
}
// Site returns information about the current site.
func (scp *ShortcodeWithPage) Site() page.Site {
return scp.Page.Site()
}
// Ref is a shortcut to the Ref method on Page. It passes itself as a context
// to get better error messages.
func (scp *ShortcodeWithPage) Ref(args map[string]any) (string, error) {
return scp.Page.RefFrom(args, scp)
}
// RelRef is a shortcut to the RelRef method on Page. It passes itself as a context
// to get better error messages.
func (scp *ShortcodeWithPage) RelRef(args map[string]any) (string, error) {
return scp.Page.RelRefFrom(args, scp)
}
// Scratch returns a scratch-pad scoped for this shortcode. This can be used
// as a temporary storage for variables, counters etc.
func (scp *ShortcodeWithPage) Scratch() *maps.Scratch {
if scp.scratch == nil {
scp.scratch = maps.NewScratch()
}
return scp.scratch
}
// Get is a convenience method to look up shortcode parameters by its key.
func (scp *ShortcodeWithPage) Get(key any) any {
if scp.Params == nil {
return nil
}
if reflect.ValueOf(scp.Params).Len() == 0 {
return nil
}
var x reflect.Value
switch key.(type) {
case int64, int32, int16, int8, int:
if reflect.TypeOf(scp.Params).Kind() == reflect.Map {
// We treat this as a non error, so people can do similar to
// {{ $myParam := .Get "myParam" | default .Get 0 }}
// Without having to do additional checks.
return nil
} else if reflect.TypeOf(scp.Params).Kind() == reflect.Slice {
idx := int(reflect.ValueOf(key).Int())
ln := reflect.ValueOf(scp.Params).Len()
if idx > ln-1 {
return ""
}
x = reflect.ValueOf(scp.Params).Index(idx)
}
case string:
if reflect.TypeOf(scp.Params).Kind() == reflect.Map {
x = reflect.ValueOf(scp.Params).MapIndex(reflect.ValueOf(key))
if !x.IsValid() {
return ""
}
} else if reflect.TypeOf(scp.Params).Kind() == reflect.Slice {
// We treat this as a non error, so people can do similar to
// {{ $myParam := .Get "myParam" | default .Get 0 }}
// Without having to do additional checks.
return nil
}
}
return x.Interface()
}
func (scp *ShortcodeWithPage) page() page.Page {
return scp.Page
}
// Note - this value must not contain any markup syntax
const shortcodePlaceholderPrefix = "HAHAHUGOSHORTCODE"
func createShortcodePlaceholder(sid string, id, ordinal int) string {
return shortcodePlaceholderPrefix + strconv.Itoa(id) + sid + strconv.Itoa(ordinal) + "HBHB"
}
type shortcode struct {
name string
isInline bool // inline shortcode. Any inner will be a Go template.
isClosing bool // whether a closing tag was provided
inner []any // string or nested shortcode
params any // map or array
ordinal int
err error
indentation string // indentation from source.
info tpl.Info // One of the output formats (arbitrary)
templs []tpl.Template // All output formats
// If set, the rendered shortcode is sent as part of the surrounding content
// to Goldmark and similar.
// Before Hug0 0.55 we didn't send any shortcode output to the markup
// renderer, and this flag told Hugo to process the {{ .Inner }} content
// separately.
// The old behaviour can be had by starting your shortcode template with:
// {{ $_hugo_config := `{ "version": 1 }`}}
doMarkup bool
// the placeholder in the source when passed to Goldmark etc.
// This also identifies the rendered shortcode.
placeholder string
pos int // the position in bytes in the source file
length int // the length in bytes in the source file
}
func (s shortcode) insertPlaceholder() bool {
return !s.doMarkup || s.configVersion() == 1
}
func (s shortcode) needsInner() bool {
return s.info != nil && s.info.ParseInfo().IsInner
}
func (s shortcode) configVersion() int {
if s.info == nil {
// Not set for inline shortcodes.
return 2
}
return s.info.ParseInfo().Config.Version
}
func (s shortcode) innerString() string {
var sb strings.Builder
for _, inner := range s.inner {
sb.WriteString(inner.(string))
}
return sb.String()
}
func (sc shortcode) String() string {
// for testing (mostly), so any change here will break tests!
var params any
switch v := sc.params.(type) {
case map[string]any:
// sort the keys so test assertions won't fail
var keys []string
for k := range v {
keys = append(keys, k)
}
sort.Strings(keys)
tmp := make(map[string]any)
for _, k := range keys {
tmp[k] = v[k]
}
params = tmp
default:
// use it as is
params = sc.params
}
return fmt.Sprintf("%s(%q, %t){%s}", sc.name, params, sc.doMarkup, sc.inner)
}
type shortcodeHandler struct {
p *pageState
s *Site
// Ordered list of shortcodes for a page.
shortcodes []*shortcode
// All the shortcode names in this set.
nameSet map[string]bool
nameSetMu sync.RWMutex
// Configuration
enableInlineShortcodes bool
}
func newShortcodeHandler(p *pageState, s *Site) *shortcodeHandler {
sh := &shortcodeHandler{
p: p,
s: s,
enableInlineShortcodes: s.ExecHelper.Sec().EnableInlineShortcodes,
shortcodes: make([]*shortcode, 0, 4),
nameSet: make(map[string]bool),
}
return sh
}
const (
innerNewlineRegexp = "\n"
innerCleanupRegexp = `\A<p>(.*)</p>\n\z`
innerCleanupExpand = "$1"
)
func prepareShortcode(
ctx context.Context,
level int,
s *Site,
tplVariants tpl.TemplateVariants,
sc *shortcode,
parent *ShortcodeWithPage,
p *pageState,
) (shortcodeRenderer, error) {
toParseErr := func(err error) error {
return p.parseError(fmt.Errorf("failed to render shortcode %q: %w", sc.name, err), p.source.parsed.Input(), sc.pos)
}
// Allow the caller to delay the rendering of the shortcode if needed.
var fn shortcodeRenderFunc = func(ctx context.Context) ([]byte, bool, error) {
r, err := doRenderShortcode(ctx, level, s, tplVariants, sc, parent, p)
if err != nil {
return nil, false, toParseErr(err)
}
b, hasVariants, err := r.renderShortcode(ctx)
if err != nil {
return nil, false, toParseErr(err)
}
return b, hasVariants, nil
}
return fn, nil
}
func doRenderShortcode(
ctx context.Context,
level int,
s *Site,
tplVariants tpl.TemplateVariants,
sc *shortcode,
parent *ShortcodeWithPage,
p *pageState,
) (shortcodeRenderer, error) {
var tmpl tpl.Template
// Tracks whether this shortcode or any of its children has template variations
// in other languages or output formats. We are currently only interested in
// the output formats, so we may get some false positives -- we
// should improve on that.
var hasVariants bool
if sc.isInline {
if !p.s.ExecHelper.Sec().EnableInlineShortcodes {
return zeroShortcode, nil
}
templName := path.Join("_inline_shortcode", p.File().Path(), sc.name)
if sc.isClosing {
templStr := sc.innerString()
var err error
tmpl, err = s.TextTmpl().Parse(templName, templStr)
if err != nil {
fe := herrors.NewFileErrorFromName(err, p.File().Filename())
pos := fe.Position()
pos.LineNumber += p.posOffset(sc.pos).LineNumber
fe = fe.UpdatePosition(pos)
return zeroShortcode, p.wrapError(fe)
}
} else {
// Re-use of shortcode defined earlier in the same page.
var found bool
tmpl, found = s.TextTmpl().Lookup(templName)
if !found {
return zeroShortcode, fmt.Errorf("no earlier definition of shortcode %q found", sc.name)
}
}
} else {
var found, more bool
tmpl, found, more = s.Tmpl().LookupVariant(sc.name, tplVariants)
if !found {
s.Log.Errorf("Unable to locate template for shortcode %q in page %q", sc.name, p.File().Path())
return zeroShortcode, nil
}
hasVariants = hasVariants || more
}
data := &ShortcodeWithPage{Ordinal: sc.ordinal, posOffset: sc.pos, indentation: sc.indentation, Params: sc.params, Page: newPageForShortcode(p), Parent: parent, Name: sc.name}
if sc.params != nil {
data.IsNamedParams = reflect.TypeOf(sc.params).Kind() == reflect.Map
}
if len(sc.inner) > 0 {
var inner string
for _, innerData := range sc.inner {
switch innerData := innerData.(type) {
case string:
inner += innerData
case *shortcode:
s, err := prepareShortcode(ctx, level+1, s, tplVariants, innerData, data, p)
if err != nil {
return zeroShortcode, err
}
ss, more, err := s.renderShortcodeString(ctx)
hasVariants = hasVariants || more
if err != nil {
return zeroShortcode, err
}
inner += ss
default:
s.Log.Errorf("Illegal state on shortcode rendering of %q in page %q. Illegal type in inner data: %s ",
sc.name, p.File().Path(), reflect.TypeOf(innerData))
return zeroShortcode, nil
}
}
// Pre Hugo 0.55 this was the behaviour even for the outer-most
// shortcode.
if sc.doMarkup && (level > 0 || sc.configVersion() == 1) {
var err error
b, err := p.pageOutput.contentRenderer.ParseAndRenderContent(ctx, []byte(inner), false)
if err != nil {
return zeroShortcode, err
}
newInner := b.Bytes()
// If the type is “” (unknown) or “markdown”, we assume the markdown
// generation has been performed. Given the input: `a line`, markdown
// specifies the HTML `<p>a line</p>\n`. When dealing with documents as a
// whole, this is OK. When dealing with an `{{ .Inner }}` block in Hugo,
// this is not so good. This code does two things:
//
// 1. Check to see if inner has a newline in it. If so, the Inner data is
// unchanged.
// 2 If inner does not have a newline, strip the wrapping <p> block and
// the newline.
switch p.m.markup {
case "", "markdown":
if match, _ := regexp.MatchString(innerNewlineRegexp, inner); !match {
cleaner, err := regexp.Compile(innerCleanupRegexp)
if err == nil {
newInner = cleaner.ReplaceAll(newInner, []byte(innerCleanupExpand))
}
}
}
// TODO(bep) we may have plain text inner templates.
data.Inner = template.HTML(newInner)
} else {
data.Inner = template.HTML(inner)
}
}
result, err := renderShortcodeWithPage(ctx, s.Tmpl(), tmpl, data)
if err != nil && sc.isInline {
fe := herrors.NewFileErrorFromName(err, p.File().Filename())
pos := fe.Position()
pos.LineNumber += p.posOffset(sc.pos).LineNumber
fe = fe.UpdatePosition(pos)
return zeroShortcode, fe
}
if len(sc.inner) == 0 && len(sc.indentation) > 0 {
b := bp.GetBuffer()
i := 0
text.VisitLinesAfter(result, func(line string) {
// The first line is correctly indented.
if i > 0 {
b.WriteString(sc.indentation)
}
i++
b.WriteString(line)
})
result = b.String()
bp.PutBuffer(b)
}
return prerenderedShortcode{s: result, hasVariants: hasVariants}, err
}
func (s *shortcodeHandler) addName(name string) {
s.nameSetMu.Lock()
defer s.nameSetMu.Unlock()
s.nameSet[name] = true
}
func (s *shortcodeHandler) transferNames(in *shortcodeHandler) {
s.nameSetMu.Lock()
defer s.nameSetMu.Unlock()
for k := range in.nameSet {
s.nameSet[k] = true
}
}
func (s *shortcodeHandler) hasName(name string) bool {
s.nameSetMu.RLock()
defer s.nameSetMu.RUnlock()
_, ok := s.nameSet[name]
return ok
}
func (s *shortcodeHandler) prepareShortcodesForPage(ctx context.Context, p *pageState, f output.Format) (map[string]shortcodeRenderer, error) {
rendered := make(map[string]shortcodeRenderer)
tplVariants := tpl.TemplateVariants{
Language: p.Language().Lang,
OutputFormat: f,
}
for _, v := range s.shortcodes {
s, err := prepareShortcode(ctx, 0, s.s, tplVariants, v, nil, p)
if err != nil {
return nil, err
}
rendered[v.placeholder] = s
}
return rendered, nil
}
// pageTokens state:
// - before: positioned just before the shortcode start
// - after: shortcode(s) consumed (plural when they are nested)
func (s *shortcodeHandler) extractShortcode(ordinal, level int, source []byte, pt *pageparser.Iterator) (*shortcode, error) {
if s == nil {
panic("handler nil")
}
sc := &shortcode{ordinal: ordinal}
// Back up one to identify any indentation.
if pt.Pos() > 0 {
pt.Backup()
item := pt.Next()
if item.IsIndentation() {
sc.indentation = item.ValStr(source)
}
}
cnt := 0
nestedOrdinal := 0
nextLevel := level + 1
closed := false
const errorPrefix = "failed to extract shortcode"
Loop:
for {
currItem := pt.Next()
switch {
case currItem.IsLeftShortcodeDelim():
next := pt.Peek()
if next.IsRightShortcodeDelim() {
// no name: {{< >}} or {{% %}}
return sc, errors.New("shortcode has no name")
}
if next.IsShortcodeClose() {
continue
}
if cnt > 0 {
// nested shortcode; append it to inner content
pt.Backup()
nested, err := s.extractShortcode(nestedOrdinal, nextLevel, source, pt)
nestedOrdinal++
if nested != nil && nested.name != "" {
s.addName(nested.name)
}
if err == nil {
sc.inner = append(sc.inner, nested)
} else {
return sc, err
}
} else {
sc.doMarkup = currItem.IsShortcodeMarkupDelimiter()
}
cnt++
case currItem.IsRightShortcodeDelim():
// we trust the template on this:
// if there's no inner, we're done
if !sc.isInline {
if !sc.info.ParseInfo().IsInner {
return sc, nil
}
}
case currItem.IsShortcodeClose():
closed = true
next := pt.Peek()
if !sc.isInline {
if !sc.needsInner() {
if next.IsError() {
// return that error, more specific
continue
}
return nil, fmt.Errorf("%s: shortcode %q does not evaluate .Inner or .InnerDeindent, yet a closing tag was provided", errorPrefix, next.ValStr(source))
}
}
if next.IsRightShortcodeDelim() {
// self-closing
pt.Consume(1)
} else {
sc.isClosing = true
pt.Consume(2)
}
return sc, nil
case currItem.IsText():
sc.inner = append(sc.inner, currItem.ValStr(source))
case currItem.IsShortcodeName():
sc.name = currItem.ValStr(source)
// Used to check if the template expects inner content.
templs := s.s.Tmpl().LookupVariants(sc.name)
if templs == nil {
return nil, fmt.Errorf("%s: template for shortcode %q not found", errorPrefix, sc.name)
}
sc.info = templs[0].(tpl.Info)
sc.templs = templs
case currItem.IsInlineShortcodeName():
sc.name = currItem.ValStr(source)
sc.isInline = true
case currItem.IsShortcodeParam():
if !pt.IsValueNext() {
continue
} else if pt.Peek().IsShortcodeParamVal() {
// named params
if sc.params == nil {
params := make(map[string]any)
params[currItem.ValStr(source)] = pt.Next().ValTyped(source)
sc.params = params
} else {
if params, ok := sc.params.(map[string]any); ok {
params[currItem.ValStr(source)] = pt.Next().ValTyped(source)
} else {
return sc, fmt.Errorf("%s: invalid state: invalid param type %T for shortcode %q, expected a map", errorPrefix, params, sc.name)
}
}
} else {
// positional params
if sc.params == nil {
var params []any
params = append(params, currItem.ValTyped(source))
sc.params = params
} else {
if params, ok := sc.params.([]any); ok {
params = append(params, currItem.ValTyped(source))
sc.params = params
} else {
return sc, fmt.Errorf("%s: invalid state: invalid param type %T for shortcode %q, expected a slice", errorPrefix, params, sc.name)
}
}
}
case currItem.IsDone():
if !currItem.IsError() {
if !closed && sc.needsInner() {
return sc, fmt.Errorf("%s: shortcode %q must be closed or self-closed", errorPrefix, sc.name)
}
}
// handled by caller
pt.Backup()
break Loop
}
}
return sc, nil
}
// Replace prefixed shortcode tokens with the real content.
// Note: This function will rewrite the input slice.
func expandShortcodeTokens(
ctx context.Context,
source []byte,
tokenHandler func(ctx context.Context, token string) ([]byte, error),
) ([]byte, error) {
start := 0
pre := []byte(shortcodePlaceholderPrefix)
post := []byte("HBHB")
pStart := []byte("<p>")
pEnd := []byte("</p>")
k := bytes.Index(source[start:], pre)
for k != -1 {
j := start + k
postIdx := bytes.Index(source[j:], post)
if postIdx < 0 {
// this should never happen, but let the caller decide to panic or not
return nil, errors.New("illegal state in content; shortcode token missing end delim")
}
end := j + postIdx + 4
key := string(source[j:end])
newVal, err := tokenHandler(ctx, key)
if err != nil {
return nil, err
}
// Issue #1148: Check for wrapping p-tags <p>
if j >= 3 && bytes.Equal(source[j-3:j], pStart) {
if (k+4) < len(source) && bytes.Equal(source[end:end+4], pEnd) {
j -= 3
end += 4
}
}
// This and other cool slice tricks: https://github.com/golang/go/wiki/SliceTricks
source = append(source[:j], append(newVal, source[end:]...)...)
start = j
k = bytes.Index(source[start:], pre)
}
return source, nil
}
func renderShortcodeWithPage(ctx context.Context, h tpl.TemplateHandler, tmpl tpl.Template, data *ShortcodeWithPage) (string, error) {
buffer := bp.GetBuffer()
defer bp.PutBuffer(buffer)
err := h.ExecuteWithContext(ctx, tmpl, buffer, data)
if err != nil {
return "", fmt.Errorf("failed to process shortcode: %w", err)
}
return buffer.String(), nil
}