1 files changed, 76 insertions, 0 deletions
diff --git a/routers/web/repo/render.go b/routers/web/repo/render.go
new file mode 100644
index 0000000..e64db03
--- /dev/null
+++ b/routers/web/repo/render.go
@@ -0,0 +1,76 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package repo
+
+import (
+	"bytes"
+	"io"
+	"net/http"
+	"path"
+
+	"code.gitea.io/gitea/modules/charset"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/markup"
+	"code.gitea.io/gitea/modules/typesniffer"
+	"code.gitea.io/gitea/modules/util"
+	"code.gitea.io/gitea/services/context"
+)
+
+// RenderFile renders a file by repos path
+func RenderFile(ctx *context.Context) {
+	blob, err := ctx.Repo.Commit.GetBlobByPath(ctx.Repo.TreePath)
+	if err != nil {
+		if git.IsErrNotExist(err) {
+			ctx.NotFound("GetBlobByPath", err)
+		} else {
+			ctx.ServerError("GetBlobByPath", err)
+		}
+		return
+	}
+
+	dataRc, err := blob.DataAsync()
+	if err != nil {
+		ctx.ServerError("DataAsync", err)
+		return
+	}
+	defer dataRc.Close()
+
+	buf := make([]byte, 1024)
+	n, _ := util.ReadAtMost(dataRc, buf)
+	buf = buf[:n]
+
+	st := typesniffer.DetectContentType(buf)
+	isTextFile := st.IsText()
+
+	rd := charset.ToUTF8WithFallbackReader(io.MultiReader(bytes.NewReader(buf), dataRc), charset.ConvertOpts{})
+	ctx.Resp.Header().Add("Content-Security-Policy", "frame-src 'self'; sandbox allow-scripts")
+
+	if markupType := markup.Type(blob.Name()); markupType == "" {
+		if isTextFile {
+			_, _ = io.Copy(ctx.Resp, rd)
+		} else {
+			http.Error(ctx.Resp, "Unsupported file type render", http.StatusInternalServerError)
+		}
+		return
+	}
+
+	err = markup.Render(&markup.RenderContext{
+		Ctx:          ctx,
+		RelativePath: ctx.Repo.TreePath,
+		Links: markup.Links{
+			Base:       ctx.Repo.RepoLink,
+			BranchPath: ctx.Repo.BranchNameSubURL(),
+			TreePath:   path.Dir(ctx.Repo.TreePath),
+		},
+		Metas:            ctx.Repo.Repository.ComposeDocumentMetas(ctx),
+		GitRepo:          ctx.Repo.GitRepo,
+		InStandalonePage: true,
+	}, rd, ctx.Resp)
+	if err != nil {
+		log.Error("Failed to render file %q: %v", ctx.Repo.TreePath, err)
+		http.Error(ctx.Resp, "Failed to render file", http.StatusInternalServerError)
+		return
+	}
+}