hugo/markup/goldmark/render_link.go
Bjørn Erik Pedersen e625088ef5
Add render template hooks for links and images
This commit also

* revises the change detection for templates used by content files in server mode.
* Adds a Page.RenderString method

Fixes #6545
Fixes #4663
Closes #6043
2019-12-18 11:44:40 +01:00

208 lines
5.1 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 goldmark
import (
"github.com/gohugoio/hugo/markup/converter/hooks"
"github.com/yuin/goldmark"
"github.com/yuin/goldmark/ast"
"github.com/yuin/goldmark/renderer"
"github.com/yuin/goldmark/renderer/html"
"github.com/yuin/goldmark/util"
)
var _ renderer.SetOptioner = (*linkRenderer)(nil)
func newLinkRenderer() renderer.NodeRenderer {
r := &linkRenderer{
Config: html.Config{
Writer: html.DefaultWriter,
},
}
return r
}
func newLinks() goldmark.Extender {
return &links{}
}
type linkContext struct {
page interface{}
destination string
title string
text string
}
func (ctx linkContext) Destination() string {
return ctx.destination
}
func (ctx linkContext) Resolved() bool {
return false
}
func (ctx linkContext) Page() interface{} {
return ctx.page
}
func (ctx linkContext) Text() string {
return ctx.text
}
func (ctx linkContext) Title() string {
return ctx.title
}
type linkRenderer struct {
html.Config
}
func (r *linkRenderer) SetOption(name renderer.OptionName, value interface{}) {
r.Config.SetOption(name, value)
}
// RegisterFuncs implements NodeRenderer.RegisterFuncs.
func (r *linkRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) {
reg.Register(ast.KindLink, r.renderLink)
reg.Register(ast.KindImage, r.renderImage)
}
// Fall back to the default Goldmark render funcs. Method below borrowed from:
// https://github.com/yuin/goldmark/blob/b611cd333a492416b56aa8d94b04a67bf0096ab2/renderer/html/html.go#L404
func (r *linkRenderer) renderDefaultImage(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
if !entering {
return ast.WalkContinue, nil
}
n := node.(*ast.Image)
_, _ = w.WriteString("<img src=\"")
if r.Unsafe || !html.IsDangerousURL(n.Destination) {
_, _ = w.Write(util.EscapeHTML(util.URLEscape(n.Destination, true)))
}
_, _ = w.WriteString(`" alt="`)
_, _ = w.Write(n.Text(source))
_ = w.WriteByte('"')
if n.Title != nil {
_, _ = w.WriteString(` title="`)
r.Writer.Write(w, n.Title)
_ = w.WriteByte('"')
}
if r.XHTML {
_, _ = w.WriteString(" />")
} else {
_, _ = w.WriteString(">")
}
return ast.WalkSkipChildren, nil
}
// Fall back to the default Goldmark render funcs. Method below borrowed from:
// https://github.com/yuin/goldmark/blob/b611cd333a492416b56aa8d94b04a67bf0096ab2/renderer/html/html.go#L404
func (r *linkRenderer) renderDefaultLink(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
n := node.(*ast.Link)
if entering {
_, _ = w.WriteString("<a href=\"")
if r.Unsafe || !html.IsDangerousURL(n.Destination) {
_, _ = w.Write(util.EscapeHTML(util.URLEscape(n.Destination, true)))
}
_ = w.WriteByte('"')
if n.Title != nil {
_, _ = w.WriteString(` title="`)
r.Writer.Write(w, n.Title)
_ = w.WriteByte('"')
}
_ = w.WriteByte('>')
} else {
_, _ = w.WriteString("</a>")
}
return ast.WalkContinue, nil
}
func (r *linkRenderer) renderImage(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
n := node.(*ast.Image)
var h *hooks.Render
ctx, ok := w.(renderContextData)
if ok {
h = ctx.RenderContext().RenderHooks
ok = h != nil && h.ImageRenderer != nil
}
if !ok {
return r.renderDefaultImage(w, source, node, entering)
}
if !entering {
return ast.WalkContinue, nil
}
err := h.ImageRenderer.Render(
w,
linkContext{
page: ctx.DocumentContext().Document,
destination: string(n.Destination),
title: string(n.Title),
text: string(n.Text(source)),
},
)
ctx.AddIdentity(h.ImageRenderer.GetIdentity())
return ast.WalkSkipChildren, err
}
func (r *linkRenderer) renderLink(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
n := node.(*ast.Link)
var h *hooks.Render
ctx, ok := w.(renderContextData)
if ok {
h = ctx.RenderContext().RenderHooks
ok = h != nil && h.LinkRenderer != nil
}
if !ok {
return r.renderDefaultLink(w, source, node, entering)
}
if !entering {
return ast.WalkContinue, nil
}
err := h.LinkRenderer.Render(
w,
linkContext{
page: ctx.DocumentContext().Document,
destination: string(n.Destination),
title: string(n.Title),
text: string(n.Text(source)),
},
)
ctx.AddIdentity(h.LinkRenderer.GetIdentity())
// Do not render the inner text.
return ast.WalkSkipChildren, err
}
type links struct {
}
// Extend implements goldmark.Extender.
func (e *links) Extend(m goldmark.Markdown) {
m.Renderer().AddOptions(renderer.WithNodeRenderers(
util.Prioritized(newLinkRenderer(), 100),
))
}