hugo/hugolib/alias.go
Bjørn Erik Pedersen a03c631c42
Rework template handling for function and map lookups
This is a big commit, but it deletes lots of code and simplifies a lot.

* Resolving the template funcs at execution time means we don't have to create template clones per site
* Having a custom map resolver means that we can remove the AST lower case transformation for the special lower case Params map

Not only is the above easier to reason about, it's also faster, especially if you have more than one language, as in the benchmark below:

```
name                          old time/op    new time/op    delta
SiteNew/Deep_content_tree-16    53.7ms ± 0%    48.1ms ± 2%  -10.38%  (p=0.029 n=4+4)

name                          old alloc/op   new alloc/op   delta
SiteNew/Deep_content_tree-16    41.0MB ± 0%    36.8MB ± 0%  -10.26%  (p=0.029 n=4+4)

name                          old allocs/op  new allocs/op  delta
SiteNew/Deep_content_tree-16      481k ± 0%      410k ± 0%  -14.66%  (p=0.029 n=4+4)
```

This should be even better if you also have lots of templates.

Closes #6594
2019-12-12 10:04:35 +01:00

174 lines
4.8 KiB
Go

// Copyright 2019 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 hugolib
import (
"bytes"
"errors"
"fmt"
"html/template"
"io"
"path"
"path/filepath"
"runtime"
"strings"
"github.com/gohugoio/hugo/common/loggers"
"github.com/gohugoio/hugo/output"
"github.com/gohugoio/hugo/publisher"
"github.com/gohugoio/hugo/resources/page"
"github.com/gohugoio/hugo/tpl"
)
var defaultAliasTemplates *template.Template
type aliasHandler struct {
t tpl.TemplateHandler
log *loggers.Logger
allowRoot bool
}
func newAliasHandler(t tpl.TemplateHandler, l *loggers.Logger, allowRoot bool) aliasHandler {
return aliasHandler{t, l, allowRoot}
}
type aliasPage struct {
Permalink string
page.Page
}
func (a aliasHandler) renderAlias(permalink string, p page.Page) (io.Reader, error) {
var templ tpl.Template
var found bool
templ, found = a.t.Lookup("alias.html")
if !found {
// TODO(bep) consolidate
templ, found = a.t.Lookup("_internal/alias.html")
if !found {
return nil, errors.New("no alias template found")
}
}
data := aliasPage{
permalink,
p,
}
buffer := new(bytes.Buffer)
err := a.t.Execute(templ, buffer, data)
if err != nil {
return nil, err
}
return buffer, nil
}
func (s *Site) writeDestAlias(path, permalink string, outputFormat output.Format, p page.Page) (err error) {
return s.publishDestAlias(false, path, permalink, outputFormat, p)
}
func (s *Site) publishDestAlias(allowRoot bool, path, permalink string, outputFormat output.Format, p page.Page) (err error) {
handler := newAliasHandler(s.Tmpl, s.Log, allowRoot)
s.Log.DEBUG.Println("creating alias:", path, "redirecting to", permalink)
targetPath, err := handler.targetPathAlias(path)
if err != nil {
return err
}
aliasContent, err := handler.renderAlias(permalink, p)
if err != nil {
return err
}
pd := publisher.Descriptor{
Src: aliasContent,
TargetPath: targetPath,
StatCounter: &s.PathSpec.ProcessingStats.Aliases,
OutputFormat: outputFormat,
}
return s.publisher.Publish(pd)
}
func (a aliasHandler) targetPathAlias(src string) (string, error) {
originalAlias := src
if len(src) <= 0 {
return "", fmt.Errorf("alias \"\" is an empty string")
}
alias := path.Clean(filepath.ToSlash(src))
if !a.allowRoot && alias == "/" {
return "", fmt.Errorf("alias \"%s\" resolves to website root directory", originalAlias)
}
components := strings.Split(alias, "/")
// Validate against directory traversal
if components[0] == ".." {
return "", fmt.Errorf("alias \"%s\" traverses outside the website root directory", originalAlias)
}
// Handle Windows file and directory naming restrictions
// See "Naming Files, Paths, and Namespaces" on MSDN
// https://msdn.microsoft.com/en-us/library/aa365247%28v=VS.85%29.aspx?f=255&MSPPError=-2147217396
msgs := []string{}
reservedNames := []string{"CON", "PRN", "AUX", "NUL", "COM0", "COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8", "COM9", "LPT0", "LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9"}
if strings.ContainsAny(alias, ":*?\"<>|") {
msgs = append(msgs, fmt.Sprintf("Alias \"%s\" contains invalid characters on Windows: : * ? \" < > |", originalAlias))
}
for _, ch := range alias {
if ch < ' ' {
msgs = append(msgs, fmt.Sprintf("Alias \"%s\" contains ASCII control code (0x00 to 0x1F), invalid on Windows: : * ? \" < > |", originalAlias))
continue
}
}
for _, comp := range components {
if strings.HasSuffix(comp, " ") || strings.HasSuffix(comp, ".") {
msgs = append(msgs, fmt.Sprintf("Alias \"%s\" contains component with a trailing space or period, problematic on Windows", originalAlias))
}
for _, r := range reservedNames {
if comp == r {
msgs = append(msgs, fmt.Sprintf("Alias \"%s\" contains component with reserved name \"%s\" on Windows", originalAlias, r))
}
}
}
if len(msgs) > 0 {
if runtime.GOOS == "windows" {
for _, m := range msgs {
a.log.ERROR.Println(m)
}
return "", fmt.Errorf("cannot create \"%s\": Windows filename restriction", originalAlias)
}
for _, m := range msgs {
a.log.INFO.Println(m)
}
}
// Add the final touch
alias = strings.TrimPrefix(alias, "/")
if strings.HasSuffix(alias, "/") {
alias = alias + "index.html"
} else if !strings.HasSuffix(alias, ".html") {
alias = alias + "/" + "index.html"
}
return filepath.FromSlash(alias), nil
}