hugo/resources/resource/resourcetypes.go
2022-01-04 17:10:39 +01:00

216 lines
6 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 resource
import (
"image"
"github.com/gohugoio/hugo/common/maps"
"github.com/gohugoio/hugo/langs"
"github.com/gohugoio/hugo/media"
"github.com/gohugoio/hugo/resources/images/exif"
"github.com/gohugoio/hugo/common/hugio"
)
// Cloner is an internal template and not meant for use in the templates. It
// may change without notice.
type Cloner interface {
Clone() Resource
}
// OriginProvider provides the original Resource if this is wrapped.
// This is an internal Hugo interface and not meant for use in the templates.
type OriginProvider interface {
Origin() Resource
GetFieldString(pattern string) (string, bool)
}
// ErrProvider provides an Err.
type ErrProvider interface {
Err() error
}
// Resource represents a linkable resource, i.e. a content page, image etc.
type Resource interface {
ResourceTypeProvider
MediaTypeProvider
ResourceLinksProvider
ResourceMetaProvider
ResourceParamsProvider
ResourceDataProvider
ErrProvider
}
// Image represents an image resource.
type Image interface {
Resource
ImageOps
}
type ImageOps interface {
Height() int
Width() int
Fill(spec string) (Image, error)
Fit(spec string) (Image, error)
Resize(spec string) (Image, error)
Filter(filters ...interface{}) (Image, error)
Exif() *exif.Exif
// Internal
DecodeImage() (image.Image, error)
}
type ResourceTypeProvider interface {
// ResourceType is the resource type. For most file types, this is the main
// part of the MIME type, e.g. "image", "application", "text" etc.
// For content pages, this value is "page".
ResourceType() string
}
type ResourceTypesProvider interface {
ResourceTypeProvider
MediaTypeProvider
}
type MediaTypeProvider interface {
// MediaType is this resource's MIME type.
MediaType() media.Type
}
type ResourceLinksProvider interface {
// Permalink represents the absolute link to this resource.
Permalink() string
// RelPermalink represents the host relative link to this resource.
RelPermalink() string
}
type ResourceMetaProvider interface {
// Name is the logical name of this resource. This can be set in the front matter
// metadata for this resource. If not set, Hugo will assign a value.
// This will in most cases be the base filename.
// So, for the image "/some/path/sunset.jpg" this will be "sunset.jpg".
// The value returned by this method will be used in the GetByPrefix and ByPrefix methods
// on Resources.
Name() string
// Title returns the title if set in front matter. For content pages, this will be the expected value.
Title() string
}
type ResourceParamsProvider interface {
// Params set in front matter for this resource.
Params() maps.Params
}
type ResourceDataProvider interface {
// Resource specific data set by Hugo.
// One example would be.Data.Digest for fingerprinted resources.
Data() interface{}
}
// ResourcesLanguageMerger describes an interface for merging resources from a
// different language.
type ResourcesLanguageMerger interface {
MergeByLanguage(other Resources) Resources
// Needed for integration with the tpl package.
MergeByLanguageInterface(other interface{}) (interface{}, error)
}
// Identifier identifies a resource.
type Identifier interface {
Key() string
}
// ContentResource represents a Resource that provides a way to get to its content.
// Most Resource types in Hugo implements this interface, including Page.
type ContentResource interface {
MediaType() media.Type
ContentProvider
}
// ContentProvider provides Content.
// This should be used with care, as it will read the file content into memory, but it
// should be cached as effectively as possible by the implementation.
type ContentProvider interface {
// Content returns this resource's content. It will be equivalent to reading the content
// that RelPermalink points to in the published folder.
// The return type will be contextual, and should be what you would expect:
// * Page: template.HTML
// * JSON: String
// * Etc.
Content() (interface{}, error)
}
// OpenReadSeekCloser allows setting some other way (than reading from a filesystem)
// to open or create a ReadSeekCloser.
type OpenReadSeekCloser func() (hugio.ReadSeekCloser, error)
// ReadSeekCloserResource is a Resource that supports loading its content.
type ReadSeekCloserResource interface {
MediaType() media.Type
hugio.ReadSeekCloserProvider
}
// LengthProvider is a Resource that provides a length
// (typically the length of the content).
type LengthProvider interface {
Len() int
}
// LanguageProvider is a Resource in a language.
type LanguageProvider interface {
Language() *langs.Language
}
// TranslationKeyProvider connects translations of the same Resource.
type TranslationKeyProvider interface {
TranslationKey() string
}
// UnmarshableResource represents a Resource that can be unmarshaled to some other format.
type UnmarshableResource interface {
ReadSeekCloserResource
Identifier
}
type resourceTypesHolder struct {
mediaType media.Type
resourceType string
}
func (r resourceTypesHolder) MediaType() media.Type {
return r.mediaType
}
func (r resourceTypesHolder) ResourceType() string {
return r.resourceType
}
func NewResourceTypesProvider(mediaType media.Type, resourceType string) ResourceTypesProvider {
return resourceTypesHolder{mediaType: mediaType, resourceType: resourceType}
}
type languageHolder struct {
lang *langs.Language
}
func (l languageHolder) Language() *langs.Language {
return l.lang
}
func NewLanguageProvider(lang *langs.Language) LanguageProvider {
return languageHolder{lang: lang}
}