Render embedded code preview by permlink in markdown

modules/indexer/code/search.go

@@ -22,7 +22,7 @@ type Result struct {
  UpdatedUnix timeutil.TimeStamp
  Language string
  Color string
- Lines []ResultLine
+ Lines []*ResultLine
 }
 
 type ResultLine struct {
@@ -70,16 +70,18 @@ func writeStrings(buf *bytes.Buffer, strs ...string) error {
  return nil
 }
 
-func HighlightSearchResultCode(filename string, lineNums []int, code string) []ResultLine {
+func HighlightSearchResultCode(filename, language string, lineNums []int, code string) []*ResultLine {
  // we should highlight the whole code block first, otherwise it doesn't work well with multiple line highlighting
- hl, _ := highlight.Code(filename, "", code)
+ hl, _ := highlight.Code(filename, language, code)
  highlightedLines := strings.Split(string(hl), "\n")
 
  // The lineNums outputted by highlight.Code might not match the original lineNums, because "highlight" removes the last `\n`
- lines := make([]ResultLine, min(len(highlightedLines), len(lineNums)))
+ lines := make([]*ResultLine, min(len(highlightedLines), len(lineNums)))
  for i := 0; i < len(lines); i++ {
- lines[i].Num = lineNums[i]
- lines[i].FormattedContent = template.HTML(highlightedLines[i])
+ lines[i] = &ResultLine{
+ Num: lineNums[i],
+ FormattedContent: template.HTML(highlightedLines[i]),
+ }
  }
  return lines
 }
@@ -122,7 +124,7 @@ func searchResult(result *internal.SearchResult, startIndex, endIndex int) (*Res
  UpdatedUnix: result.UpdatedUnix,
  Language: result.Language,
  Color: result.Color,
- Lines: HighlightSearchResultCode(result.Filename, lineNums, formattedLinesBuffer.String()),
+ Lines: HighlightSearchResultCode(result.Filename, result.Language, lineNums, formattedLinesBuffer.String()),
  }, nil
 }
 

modules/markup/html.go

@@ -171,6 +171,7 @@ type processor func(ctx *RenderContext, node *html.Node)
 var defaultProcessors = []processor{
  fullIssuePatternProcessor,
  comparePatternProcessor,
+ codePreviewPatternProcessor,
  fullHashPatternProcessor,
  shortLinkProcessor,
  linkProcessor,

modules/markup/html_codepreview.go

@@ -0,0 +1,86 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package markup
+
+import (
+ "html/template"
+ "net/url"
+ "regexp"
+ "strconv"
+ "strings"
+
+ "code.gitea.io/gitea/modules/httplib"
+ "code.gitea.io/gitea/modules/log"
+
+ "golang.org/x/net/html"
+)
+
+// codePreviewPattern matches "http://domain/.../{owner}/{repo}/src/commit/{commit}/{filepath}#L10-L20"
+var codePreviewPattern = regexp.MustCompile(`https?://\S+/([^\s/]+)/([^\s/]+)/src/commit/([0-9a-f]{7,64})(/\S+)#(L\d+(-L\d+)?)`)
+
+type RenderCodePreviewOptions struct {
+ FullURL string
+ OwnerName string
+ RepoName string
+ CommitID string
+ FilePath string
+
+ LineStart, LineStop int
+}
+
+func renderCodeBlock(ctx *RenderContext, node *html.Node) (urlPosStart, urlPosStop int, htm template.HTML, err error) {
+ m := codePreviewPattern.FindStringSubmatchIndex(node.Data)
+ if m == nil {
+ return 0, 0, "", nil
+ }
+
+ opts := RenderCodePreviewOptions{
+ FullURL: node.Data[m[0]:m[1]],
+ OwnerName: node.Data[m[2]:m[3]],
+ RepoName: node.Data[m[4]:m[5]],
+ CommitID: node.Data[m[6]:m[7]],
+ FilePath: node.Data[m[8]:m[9]],
+ }
+ if !httplib.IsCurrentGiteaSiteURL(opts.FullURL) {
+ return 0, 0, "", nil
+ }
+ u, err := url.Parse(opts.FilePath)
+ if err != nil {
+ return 0, 0, "", err
+ }
+ opts.FilePath = strings.TrimPrefix(u.Path, "/")
+
+ lineStartStr, lineStopStr, _ := strings.Cut(node.Data[m[10]:m[11]], "-")
+ lineStart, _ := strconv.Atoi(strings.TrimPrefix(lineStartStr, "L"))
+ lineStop, _ := strconv.Atoi(strings.TrimPrefix(lineStopStr, "L"))
+ opts.LineStart, opts.LineStop = lineStart, lineStop
+ h, err := DefaultProcessorHelper.RenderRepoFileCodePreview(ctx.Ctx, opts)
+ return m[0], m[1], h, err
+}
+
+func codePreviewPatternProcessor(ctx *RenderContext, node *html.Node) {
+ for node != nil {
+ if node.Type != html.TextNode {
+ node = node.NextSibling
+ continue
+ }
+ urlPosStart, urlPosEnd, h, err := renderCodeBlock(ctx, node)
+ if err != nil || h == "" {
+ if err != nil {
+ log.Error("Unable to render code preview: %v", err)
+ }
+ node = node.NextSibling
+ continue
+ }
+ next := node.NextSibling
+ textBefore := node.Data[:urlPosStart]
+ textAfter := node.Data[urlPosEnd:]
+ node.Data = textBefore
+ node.Parent.InsertBefore(&html.Node{Type: html.RawNode, Data: string(h)}, next)
+ if textAfter != "" {
+ node.Parent.InsertBefore(&html.Node{Type: html.TextNode, Data: textAfter}, next)
+ }
+ node = next
+ }
+}

modules/markup/html_codepreview_test.go

@@ -0,0 +1,34 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package markup_test
+
+import (
+ "context"
+ "html/template"
+ "strings"
+ "testing"
+
+ "code.gitea.io/gitea/modules/git"
+ "code.gitea.io/gitea/modules/markup"
+
+ "github.com/stretchr/testify/assert"
+)
+
+func TestRenderCodePreview(t *testing.T) {
+ markup.Init(&markup.ProcessorHelper{
+ RenderRepoFileCodePreview: func(ctx context.Context, opts markup.RenderCodePreviewOptions) (template.HTML, error) {
+ return "<div>code preview</div>", nil
+ },
+ })
+ test := func(input, expected string) {
+ buffer, err := markup.RenderString(&markup.RenderContext{
+ Ctx: git.DefaultContext,
+ Type: "markdown",
+ }, input)
+ assert.NoError(t, err)
+ assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(buffer))
+ }
+ test("http://localhost:3000/owner/repo/src/commit/0123456789/foo/bar.md#L10-L20", "<p><div>code preview</div></p>")
+ test("http://other/owner/repo/src/commit/0123456789/foo/bar.md#L10-L20", `<p><a href="http://other/owner/repo/src/commit/0123456789/foo/bar.md#L10-L20" rel="nofollow">http://other/owner/repo/src/commit/0123456789/foo/bar.md#L10-L20</a></p>`)
+}

modules/markup/renderer.go

@@ -8,6 +8,7 @@ import (
  "context"
  "errors"
  "fmt"
+ "html/template"
  "io"
  "net/url"
  "path/filepath"
@@ -33,6 +34,8 @@ type ProcessorHelper struct {
  IsUsernameMentionable func(ctx context.Context, username string) bool
 
  ElementDir string // the direction of the elements, eg: "ltr", "rtl", "auto", default to no direction attribute
+
+ RenderRepoFileCodePreview func(ctx context.Context, options RenderCodePreviewOptions) (template.HTML, error)
 }
 
 var DefaultProcessorHelper ProcessorHelper

modules/markup/sanitizer.go

@@ -60,6 +60,21 @@ func createDefaultPolicy() *bluemonday.Policy {
  // For JS code copy and Mermaid loading state
  policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-block( is-loading)?$`)).OnElements("pre")
 
+ // For code preview
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-preview-[-\w]+( file-content)?$`)).Globally()
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-num$`)).OnElements("td")
+ policy.AllowAttrs("data-line-number").OnElements("span")
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-code chroma$`)).OnElements("td")
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-inner$`)).OnElements("code")
+
+ // For code preview (unicode escape)
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^file-view( unicode-escaped)?$`)).OnElements("table")
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-escape$`)).OnElements("td")
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^toggle-escape-button btn interact-bg$`)).OnElements("a") // don't use button, button might submit a form
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^(ambiguous-code-point|escaped-code-point|broken-code-point)$`)).OnElements("span")
+ policy.AllowAttrs("class").Matching(regexp.MustCompile(`^char$`)).OnElements("span")
+ policy.AllowAttrs("data-tooltip-content", "data-escaped").OnElements("span")
+
  // For color preview
  policy.AllowAttrs("class").Matching(regexp.MustCompile(`^color-preview$`)).OnElements("span")
 

routers/web/repo/search.go

@@ -81,7 +81,7 @@ func Search(ctx *context.Context) {
  // UpdatedUnix: not supported yet
  // Language: not supported yet
  // Color: not supported yet
- Lines: code_indexer.HighlightSearchResultCode(r.Filename, r.LineNumbers, strings.Join(r.LineCodes, "\n")),
+ Lines: code_indexer.HighlightSearchResultCode(r.Filename, "", r.LineNumbers, strings.Join(r.LineCodes, "\n")),
  })
  }
  }

services/contexttest/context_tests.go

@@ -63,6 +63,7 @@ func MockContext(t *testing.T, reqPath string, opts ...MockContextOption) (*cont
  base.Locale = &translation.MockLocale{}
 
  ctx := context.NewWebContext(base, opt.Render, nil)
+ ctx.AppendContextValue(context.WebContextKey, ctx)
  ctx.PageData = map[string]any{}
  ctx.Data["PageStartTime"] = time.Now()
  chiCtx := chi.NewRouteContext()

services/markup/main_test.go

@@ -11,6 +11,6 @@ import (
 
 func TestMain(m *testing.M) {
  unittest.MainTest(m, &unittest.TestOptions{
- FixtureFiles: []string{"user.yml"},
+ FixtureFiles: []string{"user.yml", "repository.yml", "access.yml", "repo_unit.yml"},
  })
 }

services/markup/processorhelper.go

@@ -14,6 +14,8 @@ import (
 func ProcessorHelper() *markup.ProcessorHelper {
  return &markup.ProcessorHelper{
  ElementDir: "auto", // set dir="auto" for necessary (eg: <p>, <h?>, etc) tags
+
+ RenderRepoFileCodePreview: renderRepoFileCodePreview,
  IsUsernameMentionable: func(ctx context.Context, username string) bool {
  mentionedUser, err := user.GetUserByName(ctx, username)
  if err != nil {

services/markup/processorhelper_codepreview.go

@@ -0,0 +1,117 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package markup
+
+import (
+ "bufio"
+ "context"
+ "fmt"
+ "html/template"
+ "strings"
+
+ "code.gitea.io/gitea/models/perm/access"
+ "code.gitea.io/gitea/models/repo"
+ "code.gitea.io/gitea/models/unit"
+ "code.gitea.io/gitea/modules/charset"
+ "code.gitea.io/gitea/modules/gitrepo"
+ "code.gitea.io/gitea/modules/indexer/code"
+ "code.gitea.io/gitea/modules/markup"
+ "code.gitea.io/gitea/modules/setting"
+ gitea_context "code.gitea.io/gitea/services/context"
+ "code.gitea.io/gitea/services/repository/files"
+)
+
+func renderRepoFileCodePreview(ctx context.Context, opts markup.RenderCodePreviewOptions) (template.HTML, error) {
+ opts.LineStop = max(opts.LineStop, opts.LineStart)
+ lineCount := opts.LineStop - opts.LineStart + 1
+ if lineCount <= 0 || lineCount > 140 /* GitHub at most show 140 lines */ {
+ lineCount = 10
+ opts.LineStop = opts.LineStart + lineCount
+ }
+
+ dbRepo, err := repo.GetRepositoryByOwnerAndName(ctx, opts.OwnerName, opts.RepoName)
+ if err != nil {
+ return "", err
+ }
+
+ webCtx, ok := ctx.Value(gitea_context.WebContextKey).(*gitea_context.Context)
+ if !ok {
+ return "", fmt.Errorf("context is not a web context")
+ }
+ doer := webCtx.Doer
+
+ perms, err := access.GetUserRepoPermission(ctx, dbRepo, doer)
+ if err != nil {
+ return "", err
+ }
+ if !perms.CanRead(unit.TypeCode) {
+ return "", fmt.Errorf("no permission")
+ }
+
+ gitRepo, err := gitrepo.OpenRepository(ctx, dbRepo)
+ if err != nil {
+ return "", err
+ }
+ defer gitRepo.Close()
+
+ commit, err := gitRepo.GetCommit(opts.CommitID)
+ if err != nil {
+ return "", err
+ }
+
+ language, _ := files.TryGetContentLanguage(gitRepo, opts.CommitID, opts.FilePath)
+ blob, err := commit.GetBlobByPath(opts.FilePath)
+ if err != nil {
+ return "", err
+ }
+
+ if blob.Size() > setting.UI.MaxDisplayFileSize {
+ return "", fmt.Errorf("file is too large")
+ }
+
+ dataRc, err := blob.DataAsync()
+ if err != nil {
+ return "", err
+ }
+ defer dataRc.Close()
+
+ reader := bufio.NewReader(dataRc)
+ for i := 1; i < opts.LineStart; i++ {
+ if _, err = reader.ReadBytes('\n'); err != nil {
+ return "", err
+ }
+ }
+
+ lineNums := make([]int, 0, lineCount)
+ lineCodes := make([]string, 0, lineCount)
+ for i := opts.LineStart; i <= opts.LineStop; i++ {
+ if line, err := reader.ReadString('\n'); err != nil && line == "" {
+ break
+ } else {
+ lineNums = append(lineNums, i)
+ lineCodes = append(lineCodes, line)
+ }
+ }
+ realLineStop := max(opts.LineStart, opts.LineStart+len(lineNums)-1)
+ highlightLines := code.HighlightSearchResultCode(opts.FilePath, language, lineNums, strings.Join(lineCodes, ""))
+
+ escapeStatus := &charset.EscapeStatus{}
+ lineEscapeStatus := make([]*charset.EscapeStatus, len(highlightLines))
+ for i, hl := range highlightLines {
+ lineEscapeStatus[i], hl.FormattedContent = charset.EscapeControlHTML(hl.FormattedContent, webCtx.Base.Locale, charset.RuneNBSP)
+ escapeStatus = escapeStatus.Or(lineEscapeStatus[i])
+ }
+
+ return webCtx.RenderToHTML("base/markup_codepreview", map[string]any{
+ "FullURL": opts.FullURL,
+ "FilePath": opts.FilePath,
+ "LineStart": opts.LineStart,
+ "LineStop": realLineStop,
+ "RepoLink": dbRepo.Link(),
+ "CommitID": opts.CommitID,
+ "HighlightLines": highlightLines,
+ "EscapeStatus": escapeStatus,
+ "LineEscapeStatus": lineEscapeStatus,
+ })
+}