Initial commit (code only without large binaries)

EdgeUser/internal/web/actions/default/docs/docutils/cache.go

@@ -0,0 +1,114 @@
+// Copyright 2023 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .
+
+package docutils
+
+import (
+	"bytes"
+	chromahtml "github.com/alecthomas/chroma/v2/formatters/html"
+	"github.com/yuin/goldmark"
+	highlighting "github.com/yuin/goldmark-highlighting/v2"
+	"github.com/yuin/goldmark/extension"
+	"github.com/yuin/goldmark/parser"
+	"github.com/yuin/goldmark/renderer/html"
+	"os"
+	"path/filepath"
+	"regexp"
+	"sync"
+)
+
+type cacheItem struct {
+	ModifiedAt int64
+	Data       []byte
+}
+
+var cacheMap = map[string]*cacheItem{} // path => *cacheItem
+var cacheLocker = &sync.RWMutex{}
+
+func ReadMarkdownFile(path string, productName string, rootURL string) ([]byte, error) {
+	stat, err := os.Stat(path)
+	if err != nil {
+		return nil, err
+	}
+
+	if stat.IsDir() {
+		return nil, os.ErrNotExist
+	}
+	var modifiedAt = stat.ModTime().Unix()
+
+	cacheLocker.RLock()
+	item, ok := cacheMap[path]
+	if ok && item.ModifiedAt == modifiedAt {
+		cacheLocker.RUnlock()
+		return item.Data, nil
+	}
+	cacheLocker.RUnlock()
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return nil, err
+	}
+
+	// keywords
+	data = bytes.ReplaceAll(data, []byte("GoEdge"), []byte(productName))
+	data = bytes.ReplaceAll(data, []byte("GOEDGE"), []byte(productName))
+	data = bytes.ReplaceAll(data, []byte("http://goedge.cn"), []byte("http://example.com"))
+	data = bytes.ReplaceAll(data, []byte("https://goedge.cn"), []byte("https://example.com"))
+
+	var markdown = goldmark.New(
+		goldmark.WithParserOptions(
+			parser.WithAutoHeadingID(), // read note
+		),
+		goldmark.WithExtensions(extension.Table,
+			extension.Strikethrough,
+			highlighting.NewHighlighting(highlighting.WithStyle("github"), highlighting.WithFormatOptions(chromahtml.TabWidth(4))),
+		),
+		goldmark.WithRendererOptions(html.WithHardWraps()),
+	)
+
+	var buf = &bytes.Buffer{}
+	err = markdown.Convert(data, buf)
+	if err != nil {
+		return nil, err
+	}
+	data = buf.Bytes()
+
+	// convert links
+	{
+		var reg = regexp.MustCompile(`(?U)<a href="(.+\.md)">`)
+		data = reg.ReplaceAllFunc(data, func(link []byte) []byte {
+			var pieces = reg.FindSubmatch(link)
+			if len(pieces) > 1 {
+				var newLink = append([]byte(rootURL), bytes.TrimSuffix(pieces[1], []byte(".md"))...)
+				newLink = append(newLink, []byte(".html")...)
+				newLink = []byte(filepath.Clean(string(newLink)))
+				return bytes.ReplaceAll(link, pieces[1], newLink)
+			}
+			return link
+		})
+	}
+
+	// convert images
+	{
+		var reg = regexp.MustCompile(`(?U)<img src="(.+)"[^>]*>`)
+		data = reg.ReplaceAllFunc(data, func(link []byte) []byte {
+			var pieces = reg.FindSubmatch(link)
+			if len(pieces) > 1 {
+				var newLink = append([]byte(rootURL), pieces[1]...)
+				newLink = []byte(filepath.Clean(string(newLink)))
+				return []byte("<a href=\"" + string(newLink) + "\" target=\"_blank\">" + string(bytes.ReplaceAll(link, pieces[1], newLink)) + "</a>")
+			}
+			return link
+		})
+	}
+
+	// put into cache
+	item = &cacheItem{
+		ModifiedAt: modifiedAt,
+		Data:       data,
+	}
+	cacheLocker.Lock()
+	cacheMap[path] = item
+	cacheLocker.Unlock()
+
+	return data, nil
+}