hugo/resources/postpub/postpub.go
2020-04-07 21:59:20 +02:00

177 lines
4.5 KiB
Go

// Copyright 2020 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 postpub
import (
"fmt"
"reflect"
"strconv"
"strings"
"github.com/spf13/cast"
"github.com/gohugoio/hugo/common/maps"
"github.com/gohugoio/hugo/media"
"github.com/gohugoio/hugo/resources/resource"
)
type PostPublishedResource interface {
resource.ResourceTypeProvider
resource.ResourceLinksProvider
resource.ResourceMetaProvider
resource.ResourceParamsProvider
resource.ResourceDataProvider
resource.OriginProvider
MediaType() map[string]interface{}
}
const (
PostProcessPrefix = "__h_pp_l1"
PostProcessSuffix = "__e"
)
func NewPostPublishResource(id int, r resource.Resource) PostPublishedResource {
return &PostPublishResource{
prefix: PostProcessPrefix + "_" + strconv.Itoa(id) + "_",
delegate: r,
}
}
// postPublishResource holds a Resource to be transformed post publishing.
type PostPublishResource struct {
prefix string
delegate resource.Resource
}
func (r *PostPublishResource) field(name string) string {
return r.prefix + name + PostProcessSuffix
}
func (r *PostPublishResource) Permalink() string {
return r.field("Permalink")
}
func (r *PostPublishResource) RelPermalink() string {
return r.field("RelPermalink")
}
func (r *PostPublishResource) Origin() resource.Resource {
return r.delegate
}
func (r *PostPublishResource) GetFieldString(pattern string) (string, bool) {
if r == nil {
panic("resource is nil")
}
prefixIdx := strings.Index(pattern, r.prefix)
if prefixIdx == -1 {
// Not a method on this resource.
return "", false
}
fieldAccessor := pattern[prefixIdx+len(r.prefix) : strings.Index(pattern, PostProcessSuffix)]
d := r.delegate
switch {
case fieldAccessor == "RelPermalink":
return d.RelPermalink(), true
case fieldAccessor == "Permalink":
return d.Permalink(), true
case fieldAccessor == "Name":
return d.Name(), true
case fieldAccessor == "Title":
return d.Title(), true
case fieldAccessor == "ResourceType":
return d.ResourceType(), true
case fieldAccessor == "Content":
content, err := d.(resource.ContentProvider).Content()
if err != nil {
return "", true
}
return cast.ToString(content), true
case strings.HasPrefix(fieldAccessor, "MediaType"):
return r.fieldToString(d.MediaType(), fieldAccessor), true
case fieldAccessor == "Data.Integrity":
return cast.ToString((d.Data().(map[string]interface{})["Integrity"])), true
default:
panic(fmt.Sprintf("unknown field accessor %q", fieldAccessor))
}
}
func (r *PostPublishResource) fieldToString(receiver interface{}, path string) string {
fieldname := strings.Split(path, ".")[1]
receiverv := reflect.ValueOf(receiver)
switch receiverv.Kind() {
case reflect.Map:
v := receiverv.MapIndex(reflect.ValueOf(fieldname))
return cast.ToString(v.Interface())
default:
v := receiverv.FieldByName(fieldname)
if !v.IsValid() {
method := receiverv.MethodByName(fieldname)
if method.IsValid() {
vals := method.Call(nil)
if len(vals) > 0 {
v = vals[0]
}
}
}
if v.IsValid() {
return cast.ToString(v.Interface())
}
return ""
}
}
func (r *PostPublishResource) Data() interface{} {
m := map[string]interface{}{
"Integrity": "",
}
insertFieldPlaceholders("Data", m, r.field)
return m
}
func (r *PostPublishResource) MediaType() map[string]interface{} {
m := structToMapWithPlaceholders("MediaType", media.Type{}, r.field)
return m
}
func (r *PostPublishResource) ResourceType() string {
return r.field("ResourceType")
}
func (r *PostPublishResource) Name() string {
return r.field("Name")
}
func (r *PostPublishResource) Title() string {
return r.field("Title")
}
func (r *PostPublishResource) Params() maps.Params {
panic(r.fieldNotSupported("Params"))
}
func (r *PostPublishResource) Content() (interface{}, error) {
return r.field("Content"), nil
}
func (r *PostPublishResource) fieldNotSupported(name string) string {
return fmt.Sprintf("method .%s is currently not supported in post-publish transformations.", name)
}