ref: cb84d9816956c4de9353bc6d62d33723581bd3b4
dir: /resources/page/page_generate/generate_page_wrappers.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 page_generate
import (
"bytes"
"fmt"
"os"
"path/filepath"
"reflect"
"github.com/pkg/errors"
"github.com/gohugoio/hugo/common/maps"
"github.com/gohugoio/hugo/codegen"
"github.com/gohugoio/hugo/resources/page"
"github.com/gohugoio/hugo/source"
)
const header = `// 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.
// This file is autogenerated.
`
var (
fileInterfaceDeprecated = reflect.TypeOf((*source.FileWithoutOverlap)(nil)).Elem()
pageInterfaceDeprecated = reflect.TypeOf((*page.DeprecatedWarningPageMethods)(nil)).Elem()
pageInterface = reflect.TypeOf((*page.Page)(nil)).Elem()
packageDir = filepath.FromSlash("resources/page")
)
func Generate(c *codegen.Inspector) error {
if err := generateMarshalJSON(c); err != nil {
return errors.Wrap(err, "failed to generate JSON marshaler")
}
if err := generateDeprecatedWrappers(c); err != nil {
return errors.Wrap(err, "failed to generate deprecate wrappers")
}
if err := generateFileIsZeroWrappers(c); err != nil {
return errors.Wrap(err, "failed to generate file wrappers")
}
return nil
}
func generateMarshalJSON(c *codegen.Inspector) error {
filename := filepath.Join(c.ProjectRootDir, packageDir, "page_marshaljson.autogen.go")
f, err := os.Create(filename)
if err != nil {
return err
}
defer f.Close()
includes := []reflect.Type{pageInterface}
// Exclude these methods
excludes := []reflect.Type{
// We need to eveluate the deprecated vs JSON in the future,
// but leave them out for now.
pageInterfaceDeprecated,
// Leave this out for now. We need to revisit the author issue.
reflect.TypeOf((*page.AuthorProvider)(nil)).Elem(),
// navigation.PageMenus
// Prevent loops.
reflect.TypeOf((*page.SitesProvider)(nil)).Elem(),
reflect.TypeOf((*page.Positioner)(nil)).Elem(),
reflect.TypeOf((*page.ChildCareProvider)(nil)).Elem(),
reflect.TypeOf((*page.TreeProvider)(nil)).Elem(),
reflect.TypeOf((*page.InSectionPositioner)(nil)).Elem(),
reflect.TypeOf((*page.PaginatorProvider)(nil)).Elem(),
reflect.TypeOf((*maps.Scratcher)(nil)).Elem(),
}
methods := c.MethodsFromTypes(
includes,
excludes)
if len(methods) == 0 {
return errors.New("no methods found")
}
marshalJSON, pkgImports := methods.ToMarshalJSON(
"Page",
"github.com/gohugoio/hugo/resources/page",
// Exclusion regexps. Matches method names.
`\bPage\b`,
)
fmt.Fprintf(f, `%s
package page
%s
%s
`, header, importsString(pkgImports), marshalJSON)
return nil
}
func generateDeprecatedWrappers(c *codegen.Inspector) error {
filename := filepath.Join(c.ProjectRootDir, packageDir, "page_wrappers.autogen.go")
f, err := os.Create(filename)
if err != nil {
return err
}
defer f.Close()
// Generate a wrapper for deprecated page methods
reasons := map[string]string{
"IsDraft": "Use .Draft.",
"Hugo": "Use the global hugo function.",
"LanguagePrefix": "Use .Site.LanguagePrefix.",
"GetParam": "Use .Param or .Params.myParam.",
"RSSLink": `Use the Output Format's link, e.g. something like:
{{ with .OutputFormats.Get "RSS" }}{{ .RelPermalink }}{{ end }}`,
"URL": "Use .Permalink or .RelPermalink. If what you want is the front matter URL value, use .Params.url",
}
deprecated := func(name string, tp reflect.Type) string {
var alternative string
if tp == fileInterfaceDeprecated {
alternative = "Use .File." + name
} else {
var found bool
alternative, found = reasons[name]
if !found {
panic(fmt.Sprintf("no deprecated reason found for %q", name))
}
}
return fmt.Sprintf("helpers.Deprecated(%q, %q, false)", "Page."+name, alternative)
}
var buff bytes.Buffer
methods := c.MethodsFromTypes([]reflect.Type{fileInterfaceDeprecated, pageInterfaceDeprecated}, nil)
for _, m := range methods {
fmt.Fprint(&buff, m.Declaration("*pageDeprecated"))
fmt.Fprintln(&buff, " {")
fmt.Fprintf(&buff, "\t%s\n", deprecated(m.Name, m.Owner))
fmt.Fprintf(&buff, "\t%s\n}\n", m.Delegate("p", "p"))
}
pkgImports := append(methods.Imports(), "github.com/gohugoio/hugo/helpers")
fmt.Fprintf(f, `%s
package page
%s
// NewDeprecatedWarningPage adds deprecation warnings to the given implementation.
func NewDeprecatedWarningPage(p DeprecatedWarningPageMethods) DeprecatedWarningPageMethods {
return &pageDeprecated{p: p}
}
type pageDeprecated struct {
p DeprecatedWarningPageMethods
}
%s
`, header, importsString(pkgImports), buff.String())
return nil
}
func generateFileIsZeroWrappers(c *codegen.Inspector) error {
filename := filepath.Join(c.ProjectRootDir, packageDir, "zero_file.autogen.go")
f, err := os.Create(filename)
if err != nil {
return err
}
defer f.Close()
// Generate warnings for zero file access
warning := func(name string, tp reflect.Type) string {
msg := fmt.Sprintf(".File.%s on zero object. Wrap it in if or with: {{ with .File }}{{ .%s }}{{ end }}", name, name)
return fmt.Sprintf("z.log.Println(%q)", msg)
}
var buff bytes.Buffer
methods := c.MethodsFromTypes([]reflect.Type{reflect.TypeOf((*source.File)(nil)).Elem()}, nil)
for _, m := range methods {
if m.Name == "IsZero" {
continue
}
fmt.Fprint(&buff, m.DeclarationNamed("zeroFile"))
fmt.Fprintln(&buff, " {")
fmt.Fprintf(&buff, "\t%s\n", warning(m.Name, m.Owner))
if len(m.Out) > 0 {
fmt.Fprintln(&buff, "\treturn")
}
fmt.Fprintln(&buff, "}")
}
pkgImports := append(methods.Imports(), "github.com/gohugoio/hugo/helpers", "github.com/gohugoio/hugo/source")
fmt.Fprintf(f, `%s
package page
%s
// ZeroFile represents a zero value of source.File with warnings if invoked.
type zeroFile struct {
log *helpers.DistinctLogger
}
func NewZeroFile(log *helpers.DistinctLogger) source.File {
return zeroFile{log: log}
}
func (zeroFile) IsZero() bool {
return true
}
%s
`, header, importsString(pkgImports), buff.String())
return nil
}
func importsString(imps []string) string {
if len(imps) == 0 {
return ""
}
if len(imps) == 1 {
return fmt.Sprintf("import %q", imps[0])
}
impsStr := "import (\n"
for _, imp := range imps {
impsStr += fmt.Sprintf("%q\n", imp)
}
return impsStr + ")"
}