githaven/modules/markup/markdown/meta.go
John Olheiser b2bda11595
Fix markdown meta parsing (#12817)
* Fix meta parsing and add minimal test

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Add license

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Require first separator and add more tests

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Make fmt

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Go lets this work gracefully 🙏

Signed-off-by: jolheiser <john.olheiser@gmail.com>

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
2020-09-12 21:48:47 -04:00

52 lines
1.2 KiB
Go

// Copyright 2020 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 (
"errors"
"strings"
"gopkg.in/yaml.v2"
)
func isYAMLSeparator(line string) bool {
line = strings.TrimSpace(line)
for i := 0; i < len(line); i++ {
if line[i] != '-' {
return false
}
}
return len(line) > 2
}
// ExtractMetadata consumes a markdown file, parses YAML frontmatter,
// and returns the frontmatter metadata separated from the markdown content
func ExtractMetadata(contents string, out interface{}) (string, error) {
var front, body []string
lines := strings.Split(contents, "\n")
for idx, line := range lines {
if idx == 0 {
// First line has to be a separator
if !isYAMLSeparator(line) {
return "", errors.New("frontmatter must start with a separator line")
}
continue
}
if isYAMLSeparator(line) {
front, body = lines[1:idx], lines[idx+1:]
break
}
}
if len(front) == 0 {
return "", errors.New("could not determine metadata")
}
if err := yaml.Unmarshal([]byte(strings.Join(front, "\n")), out); err != nil {
return "", err
}
return strings.Join(body, "\n"), nil
}