gitea/modules/markup/csv/csv.go
Henrique Pimentel f7125ab61a
Add MAX_ROWS option for CSV rendering (#30268)
This solution implements a new config variable MAX_ROWS, which
corresponds to the “Maximum allowed rows to render CSV files. (0 for no
limit)” and rewrites the Render function for CSV files in markup module.
Now the render function only reads the file once, having MAX_FILE_SIZE+1
as a reader limit and MAX_ROWS as a row limit. When the file is larger
than MAX_FILE_SIZE or has more rows than MAX_ROWS, it only renders until
the limit, and displays a user-friendly warning informing that the
rendered data is not complete, in the user's language.

---

Previously, when a CSV file was larger than the limit, the render
function lost its function to render the code. There were also multiple
reads to the file, in order to determine its size and render or
pre-render.

The warning: ![image](https://s3.amazonaws.com/i.snag.gy/vcKh90.jpg)
2024-06-06 16:06:59 +08:00

158 lines
3.8 KiB
Go

// Copyright 2018 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package markup
import (
"bufio"
"html"
"io"
"regexp"
"strconv"
"code.gitea.io/gitea/modules/csv"
"code.gitea.io/gitea/modules/markup"
"code.gitea.io/gitea/modules/setting"
"code.gitea.io/gitea/modules/translation"
"code.gitea.io/gitea/modules/util"
)
func init() {
markup.RegisterRenderer(Renderer{})
}
// Renderer implements markup.Renderer for csv files
type Renderer struct{}
// Name implements markup.Renderer
func (Renderer) Name() string {
return "csv"
}
// Extensions implements markup.Renderer
func (Renderer) Extensions() []string {
return []string{".csv", ".tsv"}
}
// SanitizerRules implements markup.Renderer
func (Renderer) SanitizerRules() []setting.MarkupSanitizerRule {
return []setting.MarkupSanitizerRule{
{Element: "table", AllowAttr: "class", Regexp: regexp.MustCompile(`data-table`)},
{Element: "th", AllowAttr: "class", Regexp: regexp.MustCompile(`line-num`)},
{Element: "td", AllowAttr: "class", Regexp: regexp.MustCompile(`line-num`)},
}
}
func writeField(w io.Writer, element, class, field string) error {
if _, err := io.WriteString(w, "<"); err != nil {
return err
}
if _, err := io.WriteString(w, element); err != nil {
return err
}
if len(class) > 0 {
if _, err := io.WriteString(w, " class=\""); err != nil {
return err
}
if _, err := io.WriteString(w, class); err != nil {
return err
}
if _, err := io.WriteString(w, "\""); err != nil {
return err
}
}
if _, err := io.WriteString(w, ">"); err != nil {
return err
}
if _, err := io.WriteString(w, html.EscapeString(field)); err != nil {
return err
}
if _, err := io.WriteString(w, "</"); err != nil {
return err
}
if _, err := io.WriteString(w, element); err != nil {
return err
}
_, err := io.WriteString(w, ">")
return err
}
// Render implements markup.Renderer
func (r Renderer) Render(ctx *markup.RenderContext, input io.Reader, output io.Writer) error {
tmpBlock := bufio.NewWriter(output)
maxSize := setting.UI.CSV.MaxFileSize
maxRows := setting.UI.CSV.MaxRows
if maxSize != 0 {
input = io.LimitReader(input, maxSize+1)
}
rd, err := csv.CreateReaderAndDetermineDelimiter(ctx, input)
if err != nil {
return err
}
if _, err := tmpBlock.WriteString(`<table class="data-table">`); err != nil {
return err
}
row := 0
for {
fields, err := rd.Read()
if err == io.EOF || (row >= maxRows && maxRows != 0) {
break
}
if err != nil {
continue
}
if _, err := tmpBlock.WriteString("<tr>"); err != nil {
return err
}
element := "td"
if row == 0 {
element = "th"
}
if err := writeField(tmpBlock, element, "line-num", strconv.Itoa(row+1)); err != nil {
return err
}
for _, field := range fields {
if err := writeField(tmpBlock, element, "", field); err != nil {
return err
}
}
if _, err := tmpBlock.WriteString("</tr>"); err != nil {
return err
}
row++
}
if _, err = tmpBlock.WriteString("</table>"); err != nil {
return err
}
// Check if maxRows or maxSize is reached, and if true, warn.
if (row >= maxRows && maxRows != 0) || (rd.InputOffset() >= maxSize && maxSize != 0) {
warn := `<table class="data-table"><tr><td>`
rawLink := ` <a href="` + ctx.Links.RawLink() + `/` + util.PathEscapeSegments(ctx.RelativePath) + `">`
// Try to get the user translation
if locale, ok := ctx.Ctx.Value(translation.ContextKey).(translation.Locale); ok {
warn += locale.TrString("repo.file_too_large")
rawLink += locale.TrString("repo.file_view_raw")
} else {
warn += "The file is too large to be shown."
rawLink += "View Raw"
}
warn += rawLink + `</a></td></tr></table>`
// Write the HTML string to the output
if _, err := tmpBlock.WriteString(warn); err != nil {
return err
}
}
return tmpBlock.Flush()
}