hugo/tpl/template.go
Bjørn Erik Pedersen c6d650c8c8
tpl/tplimpl: Rework template management to get rid of concurrency issues
This more or less completes the simplification of the template handling code in Hugo started in v0.62.

The main motivation was to fix a long lasting issue about a crash in HTML content files  without front matter.

But this commit also comes with a big functional improvement.

As we now have moved the base template evaluation to the build stage we now use the same lookup rules for `baseof` as for `list` etc. type of templates.

This means that in this simple example you can have a `baseof` template for the `blog` section without having to duplicate the others:

```
layouts
├── _default
│   ├── baseof.html
│   ├── list.html
│   └── single.html
└── blog
    └── baseof.html
```

Also, when simplifying code, you often get rid of some double work, as shown in the "site building" benchmarks below.

These benchmarks looks suspiciously good, but I have repeated the below with ca. the same result. Compared to master:

```
name                              old time/op    new time/op    delta
SiteNew/Bundle_with_image-16        13.1ms ± 1%    10.5ms ± 1%  -19.34%  (p=0.029 n=4+4)
SiteNew/Bundle_with_JSON_file-16    13.0ms ± 0%    10.7ms ± 1%  -18.05%  (p=0.029 n=4+4)
SiteNew/Tags_and_categories-16      46.4ms ± 2%    43.1ms ± 1%   -7.15%  (p=0.029 n=4+4)
SiteNew/Canonify_URLs-16            52.2ms ± 2%    47.8ms ± 1%   -8.30%  (p=0.029 n=4+4)
SiteNew/Deep_content_tree-16        77.9ms ± 1%    70.9ms ± 1%   -9.01%  (p=0.029 n=4+4)
SiteNew/Many_HTML_templates-16      43.0ms ± 0%    37.2ms ± 1%  -13.54%  (p=0.029 n=4+4)
SiteNew/Page_collections-16         58.2ms ± 1%    52.4ms ± 1%   -9.95%  (p=0.029 n=4+4)

name                              old alloc/op   new alloc/op   delta
SiteNew/Bundle_with_image-16        3.81MB ± 0%    2.22MB ± 0%  -41.70%  (p=0.029 n=4+4)
SiteNew/Bundle_with_JSON_file-16    3.60MB ± 0%    2.01MB ± 0%  -44.20%  (p=0.029 n=4+4)
SiteNew/Tags_and_categories-16      19.3MB ± 1%    14.1MB ± 0%  -26.91%  (p=0.029 n=4+4)
SiteNew/Canonify_URLs-16            70.7MB ± 0%    69.0MB ± 0%   -2.40%  (p=0.029 n=4+4)
SiteNew/Deep_content_tree-16        37.1MB ± 0%    31.2MB ± 0%  -15.94%  (p=0.029 n=4+4)
SiteNew/Many_HTML_templates-16      17.6MB ± 0%    10.6MB ± 0%  -39.92%  (p=0.029 n=4+4)
SiteNew/Page_collections-16         25.9MB ± 0%    21.2MB ± 0%  -17.99%  (p=0.029 n=4+4)

name                              old allocs/op  new allocs/op  delta
SiteNew/Bundle_with_image-16         52.3k ± 0%     26.1k ± 0%  -50.18%  (p=0.029 n=4+4)
SiteNew/Bundle_with_JSON_file-16     52.3k ± 0%     26.1k ± 0%  -50.16%  (p=0.029 n=4+4)
SiteNew/Tags_and_categories-16        336k ± 1%      269k ± 0%  -19.90%  (p=0.029 n=4+4)
SiteNew/Canonify_URLs-16              422k ± 0%      395k ± 0%   -6.43%  (p=0.029 n=4+4)
SiteNew/Deep_content_tree-16          401k ± 0%      313k ± 0%  -21.79%  (p=0.029 n=4+4)
SiteNew/Many_HTML_templates-16        247k ± 0%      143k ± 0%  -42.17%  (p=0.029 n=4+4)
SiteNew/Page_collections-16           282k ± 0%      207k ± 0%  -26.55%  (p=0.029 n=4+4)
```

Fixes #6716
Fixes #6760
Fixes #6768
Fixes #6778
2020-01-22 09:39:49 +01:00

142 lines
3.7 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 tpl
import (
"reflect"
"io"
"regexp"
"github.com/gohugoio/hugo/output"
texttemplate "github.com/gohugoio/hugo/tpl/internal/go_templates/texttemplate"
)
// TemplateManager manages the collection of templates.
type TemplateManager interface {
TemplateHandler
TemplateFuncGetter
AddTemplate(name, tpl string) error
AddLateTemplate(name, tpl string) error
MarkReady() error
}
// TemplateVariants describes the possible variants of a template.
// All of these may be empty.
type TemplateVariants struct {
Language string
OutputFormat output.Format
}
// TemplateFinder finds templates.
type TemplateFinder interface {
TemplateLookup
TemplateLookupVariant
}
// TemplateHandler finds and executes templates.
type TemplateHandler interface {
TemplateFinder
Execute(t Template, wr io.Writer, data interface{}) error
LookupLayout(d output.LayoutDescriptor, f output.Format) (Template, bool, error)
HasTemplate(name string) bool
}
type TemplateLookup interface {
Lookup(name string) (Template, bool)
}
type TemplateLookupVariant interface {
// TODO(bep) this currently only works for shortcodes.
// We may unify and expand this variant pattern to the
// other templates, but we need this now for the shortcodes to
// quickly determine if a shortcode has a template for a given
// output format.
// It returns the template, if it was found or not and if there are
// alternative representations (output format, language).
// We are currently only interested in output formats, so we should improve
// this for speed.
LookupVariant(name string, variants TemplateVariants) (Template, bool, bool)
}
// Template is the common interface between text/template and html/template.
type Template interface {
Name() string
Prepare() (*texttemplate.Template, error)
}
// TemplateParser is used to parse ad-hoc templates, e.g. in the Resource chain.
type TemplateParser interface {
Parse(name, tpl string) (Template, error)
}
// TemplateParseFinder provides both parsing and finding.
type TemplateParseFinder interface {
TemplateParser
TemplateFinder
}
// TemplateDebugger prints some debug info to stdoud.
type TemplateDebugger interface {
Debug()
}
// templateInfo wraps a Template with some additional information.
type templateInfo struct {
Template
Info
}
// templateInfo wraps a Template with some additional information.
type templateInfoManager struct {
Template
InfoManager
}
// TemplatesProvider as implemented by deps.Deps.
type TemplatesProvider interface {
Tmpl() TemplateHandler
TextTmpl() TemplateParseFinder
}
// WithInfo wraps the info in a template.
func WithInfo(templ Template, info Info) Template {
if manager, ok := info.(InfoManager); ok {
return &templateInfoManager{
Template: templ,
InfoManager: manager,
}
}
return &templateInfo{
Template: templ,
Info: info,
}
}
var baseOfRe = regexp.MustCompile("template: (.*?):")
func extractBaseOf(err string) string {
m := baseOfRe.FindStringSubmatch(err)
if len(m) == 2 {
return m[1]
}
return ""
}
// TemplateFuncGetter allows to find a template func by name.
type TemplateFuncGetter interface {
GetFunc(name string) (reflect.Value, bool)
}