hugo/transform/metainject/hugogenerator.go

56 lines
1.7 KiB
Go

// Copyright 2018 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package metainject
import (
"bytes"
"fmt"
"regexp"
"github.com/gohugoio/hugo/common/hugo"
"github.com/gohugoio/hugo/helpers"
"github.com/gohugoio/hugo/transform"
)
var (
metaTagsCheck = regexp.MustCompile(`(?i)<meta\s+name=['|"]?generator['|"]?`)
hugoGeneratorTag = fmt.Sprintf(`<meta name="generator" content="Hugo %s">`, hugo.CurrentVersion)
)
// HugoGenerator injects a meta generator tag for Hugo if none present.
func HugoGenerator(ft transform.FromTo) error {
b := ft.From().Bytes()
if metaTagsCheck.Match(b) {
if _, err := ft.To().Write(b); err != nil {
helpers.DistinctWarnLog.Println("Failed to inject Hugo generator tag:", err)
}
return nil
}
head := "<head>"
replace := []byte(fmt.Sprintf("%s\n\t%s", head, hugoGeneratorTag))
newcontent := bytes.Replace(b, []byte(head), replace, 1)
if len(newcontent) == len(b) {
head := "<HEAD>"
replace := []byte(fmt.Sprintf("%s\n\t%s", head, hugoGeneratorTag))
newcontent = bytes.Replace(b, []byte(head), replace, 1)
}
if _, err := ft.To().Write(newcontent); err != nil {
helpers.DistinctWarnLog.Println("Failed to inject Hugo generator tag:", err)
}
return nil
}