forgejo/modules/markup/markdown/markdown.go
zeripath 2a03e96bce
Allow markdown files to read from the LFS ()
This PR makes it possible for the markdown renderer to render images and media straight from the LFS.

Fix 

Signed-off-by: Andrew Thornton [art27@cantab.net](mailto:art27@cantab.net)
2019-02-12 15:09:43 +00:00

202 lines
6 KiB
Go

// Copyright 2014 The Gogs Authors. All rights reserved.
// Copyright 2018 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package markdown
import (
"bytes"
"strings"
"code.gitea.io/gitea/modules/markup"
"code.gitea.io/gitea/modules/setting"
"code.gitea.io/gitea/modules/util"
"github.com/russross/blackfriday"
)
// Renderer is a extended version of underlying render object.
type Renderer struct {
blackfriday.Renderer
URLPrefix string
IsWiki bool
}
var byteMailto = []byte("mailto:")
// Link defines how formal links should be processed to produce corresponding HTML elements.
func (r *Renderer) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
// special case: this is not a link, a hash link or a mailto:, so it's a
// relative URL
if len(link) > 0 && !markup.IsLink(link) &&
link[0] != '#' && !bytes.HasPrefix(link, byteMailto) {
lnk := string(link)
if r.IsWiki {
lnk = util.URLJoin("wiki", lnk)
}
mLink := util.URLJoin(r.URLPrefix, lnk)
link = []byte(mLink)
}
if len(content) > 10 && string(content[0:9]) == "<a href=\"" && bytes.Contains(content[9:], []byte("<img")) {
// Image with link case: markdown `[![]()]()`
// If the content is an image, then we change the original href around it
// which points to itself to a new address "link"
rightQuote := bytes.Index(content[9:], []byte("\""))
content = bytes.Replace(content, content[9:9+rightQuote], link, 1)
out.Write(content)
} else {
r.Renderer.Link(out, link, title, content)
}
}
// List renders markdown bullet or digit lists to HTML
func (r *Renderer) List(out *bytes.Buffer, text func() bool, flags int) {
marker := out.Len()
if out.Len() > 0 {
out.WriteByte('\n')
}
if flags&blackfriday.LIST_TYPE_DEFINITION != 0 {
out.WriteString("<dl>")
} else if flags&blackfriday.LIST_TYPE_ORDERED != 0 {
out.WriteString("<ol class='ui list'>")
} else {
out.WriteString("<ul class='ui list'>")
}
if !text() {
out.Truncate(marker)
return
}
if flags&blackfriday.LIST_TYPE_DEFINITION != 0 {
out.WriteString("</dl>\n")
} else if flags&blackfriday.LIST_TYPE_ORDERED != 0 {
out.WriteString("</ol>\n")
} else {
out.WriteString("</ul>\n")
}
}
// ListItem defines how list items should be processed to produce corresponding HTML elements.
func (r *Renderer) ListItem(out *bytes.Buffer, text []byte, flags int) {
// Detect procedures to draw checkboxes.
prefix := ""
if bytes.HasPrefix(text, []byte("<p>")) {
prefix = "<p>"
}
switch {
case bytes.HasPrefix(text, []byte(prefix+"[ ] ")):
text = append([]byte(`<span class="ui fitted disabled checkbox"><input type="checkbox" disabled="disabled" /><label /></span>`), text[3+len(prefix):]...)
if prefix != "" {
text = bytes.Replace(text, []byte(prefix), []byte{}, 1)
}
case bytes.HasPrefix(text, []byte(prefix+"[x] ")):
text = append([]byte(`<span class="ui checked fitted disabled checkbox"><input type="checkbox" checked="" disabled="disabled" /><label /></span>`), text[3+len(prefix):]...)
if prefix != "" {
text = bytes.Replace(text, []byte(prefix), []byte{}, 1)
}
}
r.Renderer.ListItem(out, text, flags)
}
// Image defines how images should be processed to produce corresponding HTML elements.
func (r *Renderer) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
prefix := r.URLPrefix
if r.IsWiki {
prefix = util.URLJoin(prefix, "wiki", "raw")
}
prefix = strings.Replace(prefix, "/src/", "/media/", 1)
if len(link) > 0 && !markup.IsLink(link) {
lnk := string(link)
lnk = util.URLJoin(prefix, lnk)
lnk = strings.Replace(lnk, " ", "+", -1)
link = []byte(lnk)
}
// Put a link around it pointing to itself by default
out.WriteString(`<a href="`)
out.Write(link)
out.WriteString(`">`)
r.Renderer.Image(out, link, title, alt)
out.WriteString("</a>")
}
const (
blackfridayExtensions = 0 |
blackfriday.EXTENSION_NO_INTRA_EMPHASIS |
blackfriday.EXTENSION_TABLES |
blackfriday.EXTENSION_FENCED_CODE |
blackfriday.EXTENSION_STRIKETHROUGH |
blackfriday.EXTENSION_NO_EMPTY_LINE_BEFORE_BLOCK
blackfridayHTMLFlags = 0 |
blackfriday.HTML_SKIP_STYLE |
blackfriday.HTML_OMIT_CONTENTS |
blackfriday.HTML_USE_SMARTYPANTS
)
// RenderRaw renders Markdown to HTML without handling special links.
func RenderRaw(body []byte, urlPrefix string, wikiMarkdown bool) []byte {
renderer := &Renderer{
Renderer: blackfriday.HtmlRenderer(blackfridayHTMLFlags, "", ""),
URLPrefix: urlPrefix,
IsWiki: wikiMarkdown,
}
exts := blackfridayExtensions
if setting.Markdown.EnableHardLineBreak {
exts |= blackfriday.EXTENSION_HARD_LINE_BREAK
}
body = blackfriday.Markdown(body, renderer, exts)
return body
}
var (
// MarkupName describes markup's name
MarkupName = "markdown"
)
func init() {
markup.RegisterParser(Parser{})
}
// Parser implements markup.Parser
type Parser struct {
}
// Name implements markup.Parser
func (Parser) Name() string {
return MarkupName
}
// Extensions implements markup.Parser
func (Parser) Extensions() []string {
return setting.Markdown.FileExtensions
}
// Render implements markup.Parser
func (Parser) Render(rawBytes []byte, urlPrefix string, metas map[string]string, isWiki bool) []byte {
return RenderRaw(rawBytes, urlPrefix, isWiki)
}
// Render renders Markdown to HTML with all specific handling stuff.
func Render(rawBytes []byte, urlPrefix string, metas map[string]string) []byte {
return markup.Render("a.md", rawBytes, urlPrefix, metas)
}
// RenderString renders Markdown to HTML with special links and returns string type.
func RenderString(raw, urlPrefix string, metas map[string]string) string {
return markup.RenderString("a.md", raw, urlPrefix, metas)
}
// RenderWiki renders markdown wiki page to HTML and return HTML string
func RenderWiki(rawBytes []byte, urlPrefix string, metas map[string]string) string {
return markup.RenderWiki("a.md", rawBytes, urlPrefix, metas)
}
// IsMarkdownFile reports whether name looks like a Markdown file
// based on its extension.
func IsMarkdownFile(name string) bool {
return markup.IsMarkupFile(name, MarkupName)
}