resources: Move resource interfaces into its own package

41 files changed, 461 insertions, 377 deletions

diff --git a/deps/deps.go b/deps/deps.go
index 7fba0e153..628019961 100644
--- a/deps/deps.go
+++ b/deps/deps.go
@@ -16,7 +16,7 @@ import (
 	"github.com/gohugoio/hugo/media"
 	"github.com/gohugoio/hugo/metrics"
 	"github.com/gohugoio/hugo/output"
-	"github.com/gohugoio/hugo/resource"
+	"github.com/gohugoio/hugo/resources"
 	"github.com/gohugoio/hugo/source"
 	"github.com/gohugoio/hugo/tpl"
 	jww "github.com/spf13/jwalterweatherman"
@@ -52,7 +52,7 @@ type Deps struct {
 	SourceSpec *source.SourceSpec `json:"-"`
 
 	// The Resource Spec to use
-	ResourceSpec *resource.Spec
+	ResourceSpec *resources.Spec
 
 	// The configuration to use
 	Cfg config.Provider `json:"-"`
@@ -214,7 +214,7 @@ func New(cfg DepsCfg) (*Deps, error) {
 		return nil, errors.WithMessage(err, "failed to create file caches from configuration")
 	}
 
-	resourceSpec, err := resource.NewSpec(ps, fileCaches, logger, cfg.OutputFormats, cfg.MediaTypes)
+	resourceSpec, err := resources.NewSpec(ps, fileCaches, logger, cfg.OutputFormats, cfg.MediaTypes)
 	if err != nil {
 		return nil, err
 	}
@@ -281,7 +281,7 @@ func (d Deps) ForLanguage(cfg DepsCfg, onCreated func(d *Deps) error) (*Deps, er
 	// The resource cache is global so reuse.
 	// TODO(bep) clean up these inits.
 	resourceCache := d.ResourceSpec.ResourceCache
-	d.ResourceSpec, err = resource.NewSpec(d.PathSpec, d.ResourceSpec.FileCaches, d.Log, cfg.OutputFormats, cfg.MediaTypes)
+	d.ResourceSpec, err = resources.NewSpec(d.PathSpec, d.ResourceSpec.FileCaches, d.Log, cfg.OutputFormats, cfg.MediaTypes)
 	if err != nil {
 		return nil, err
 	}
diff --git a/hugolib/collections.go b/hugolib/collections.go
index b9992c425..cf75d3732 100644
--- a/hugolib/collections.go
+++ b/hugolib/collections.go
@@ -16,7 +16,7 @@ package hugolib
 import (
 	"fmt"
 
-	"github.com/gohugoio/hugo/resource"
+	"github.com/gohugoio/hugo/resources/resource"
 
 	"github.com/gohugoio/hugo/common/collections"
 )
diff --git a/hugolib/page.go b/hugolib/page.go
index 9f09dc9bd..71070d1e8 100644
--- a/hugolib/page.go
+++ b/hugolib/page.go
@@ -35,7 +35,7 @@ import (
 
 	"github.com/gohugoio/hugo/helpers"
 	"github.com/gohugoio/hugo/hugolib/pagemeta"
-	"github.com/gohugoio/hugo/resource"
+	"github.com/gohugoio/hugo/resources/resource"
 
 	"github.com/gohugoio/hugo/output"
 	"github.com/mitchellh/mapstructure"
diff --git a/hugolib/page_output.go b/hugolib/page_output.go
index 9a6531207..0a3eef9a6 100644
--- a/hugolib/page_output.go
+++ b/hugolib/page_output.go
@@ -24,7 +24,7 @@ import (
 
 	"github.com/gohugoio/hugo/tpl"
 
-	"github.com/gohugoio/hugo/resource"
+	"github.com/gohugoio/hugo/resources/resource"
 
 	"github.com/gohugoio/hugo/media"
 
diff --git a/hugolib/page_resource.go b/hugolib/page_resource.go
index 808a692da..201076e8b 100644
--- a/hugolib/page_resource.go
+++ b/hugolib/page_resource.go
@@ -14,7 +14,7 @@
 package hugolib
 
 import (
-	"github.com/gohugoio/hugo/resource"
+	"github.com/gohugoio/hugo/resources/resource"
 )
 
 var (
diff --git a/hugolib/pagebundler_handlers.go b/hugolib/pagebundler_handlers.go
index fdff76e24..2df1f8765 100644
--- a/hugolib/pagebundler_handlers.go
+++ b/hugolib/pagebundler_handlers.go
@@ -22,7 +22,8 @@ import (
 	"strings"
 
 	"github.com/gohugoio/hugo/helpers"
-	"github.com/gohugoio/hugo/resource"
+	"github.com/gohugoio/hugo/resources"
+	"github.com/gohugoio/hugo/resources/resource"
 )
 
 var (
@@ -255,7 +256,7 @@ func (c *contentHandlers) parsePage(h contentHandler) contentHandler {
 
 			// Assign metadata from front matter if set
 			if len(p.resourcesMetadata) > 0 {
-				resource.AssignMetadata(p.resourcesMetadata, p.Resources...)
+				resources.AssignMetadata(p.resourcesMetadata, p.Resources...)
 			}
 
 		}
@@ -309,7 +310,7 @@ func (c *contentHandlers) createResource() contentHandler {
 		}
 
 		resource, err := c.s.ResourceSpec.New(
-			resource.ResourceSourceDescriptor{
+			resources.ResourceSourceDescriptor{
 				TargetPathBuilder: ctx.parentPage.subResourceTargetPathFactory,
 				SourceFile:        ctx.source,
 				RelTargetFilename: ctx.target,
diff --git a/hugolib/pages_language_merge_test.go b/hugolib/pages_language_merge_test.go
index 6706af3bc..efcfbf04b 100644
--- a/hugolib/pages_language_merge_test.go
+++ b/hugolib/pages_language_merge_test.go
@@ -17,7 +17,7 @@ import (
 	"fmt"
 	"testing"
 
-	"github.com/gohugoio/hugo/resource"
+	"github.com/gohugoio/hugo/resources/resource"
 	"github.com/stretchr/testify/require"
 )
 
diff --git a/hugolib/resource_chain_test.go b/hugolib/resource_chain_test.go
index 0fe9c70c1..f53ab4966 100644
--- a/hugolib/resource_chain_test.go
+++ b/hugolib/resource_chain_test.go
@@ -25,7 +25,7 @@ import (
 	"github.com/gohugoio/hugo/hugofs"
 
 	"github.com/gohugoio/hugo/common/loggers"
-	"github.com/gohugoio/hugo/resource/resource_transformers/tocss/scss"
+	"github.com/gohugoio/hugo/resources/resource_transformers/tocss/scss"
 )
 
 func TestSCSSWithIncludePaths(t *testing.T) {
diff --git a/hugolib/site.go b/hugolib/site.go
index 9c225b332..43b398b70 100644
--- a/hugolib/site.go
+++ b/hugolib/site.go
@@ -39,7 +39,6 @@ import (
 	"github.com/gohugoio/hugo/common/hugo"
 	"github.com/gohugoio/hugo/common/maps"
 	"github.com/gohugoio/hugo/publisher"
-	"github.com/gohugoio/hugo/resource"
 	_errors "github.com/pkg/errors"
 
 	"github.com/gohugoio/hugo/langs"
@@ -62,6 +61,7 @@ import (
 	"github.com/gohugoio/hugo/hugolib/pagemeta"
 	"github.com/gohugoio/hugo/output"
 	"github.com/gohugoio/hugo/related"
+	"github.com/gohugoio/hugo/resources"
 	"github.com/gohugoio/hugo/source"
 	"github.com/gohugoio/hugo/tpl"
 	"github.com/spf13/afero"
@@ -760,7 +760,7 @@ func (s *Site) processPartial(events []fsnotify.Event) (whatChanged, error) {
 	cachePartitions := make([]string, len(events))
 
 	for i, ev := range events {
-		cachePartitions[i] = resource.ResourceKeyPartition(ev.Name)
+		cachePartitions[i] = resources.ResourceKeyPartition(ev.Name)
 
 		if s.isContentDirEvent(ev) {
 			logger.Println("Source changed", ev)
diff --git a/resource/image.go b/resources/image.go
index 6dea4cbb8..d46facac5 100644
--- a/resource/image.go
+++ b/resources/image.go
@@ -1,4 +1,4 @@
-// Copyright 2017-present The Hugo Authors. All rights reserved.
+// 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.
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package resource
+package resources
 
 import (
 	"errors"
@@ -27,6 +27,8 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/gohugoio/hugo/resources/resource"
+
 	_errors "github.com/pkg/errors"
 
 	"github.com/disintegration/imaging"
@@ -43,9 +45,9 @@ import (
 )
 
 var (
-	_ Resource = (*Image)(nil)
-	_ Source   = (*Image)(nil)
-	_ Cloner   = (*Image)(nil)
+	_ resource.Resource = (*Image)(nil)
+	_ resource.Source   = (*Image)(nil)
+	_ resource.Cloner   = (*Image)(nil)
 )
 
 // Imaging contains default image processing configuration. This will be fetched
@@ -146,7 +148,7 @@ func (i *Image) Height() int {
 }
 
 // WithNewBase implements the Cloner interface.
-func (i *Image) WithNewBase(base string) Resource {
+func (i *Image) WithNewBase(base string) resource.Resource {
 	return &Image{
 		imaging:         i.imaging,
 		format:          i.format,
diff --git a/resource/image_cache.go b/resources/image_cache.go
index 8cc626caf..58be839b3 100644
--- a/resource/image_cache.go
+++ b/resources/image_cache.go
@@ -1,4 +1,4 @@
-// Copyright 2018 The Hugo Authors. All rights reserved.
+// 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.
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package resource
+package resources
 
 import (
 	"fmt"
diff --git a/resource/image_test.go b/resources/image_test.go
index 07eab5d56..ffa482296 100644
--- a/resource/image_test.go
+++ b/resources/image_test.go
@@ -1,4 +1,4 @@
-// Copyright 2018 The Hugo Authors. All rights reserved.
+// 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.
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package resource
+package resources
 
 import (
 	"fmt"
diff --git a/resources/internal/glob.go b/resources/internal/glob.go
new file mode 100644
index 000000000..a87a23f13
--- /dev/null
+++ b/resources/internal/glob.go
@@ -0,0 +1,48 @@
+// 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 internal
+
+import (
+	"strings"
+	"sync"
+
+	"github.com/gobwas/glob"
+)
+
+var (
+	globCache = make(map[string]glob.Glob)
+	globMu    sync.RWMutex
+)
+
+func GetGlob(pattern string) (glob.Glob, error) {
+	var g glob.Glob
+
+	globMu.RLock()
+	g, found := globCache[pattern]
+	globMu.RUnlock()
+	if !found {
+		var err error
+		g, err = glob.Compile(strings.ToLower(pattern), '/')
+		if err != nil {
+			return nil, err
+		}
+
+		globMu.Lock()
+		globCache[pattern] = g
+		globMu.Unlock()
+	}
+
+	return g, nil
+
+}
diff --git a/resource/resource.go b/resources/resource.go
index 0f5a43648..742903e80 100644
--- a/resource/resource.go
+++ b/resources/resource.go
@@ -1,4 +1,4 @@
-// Copyright 2018 The Hugo Authors. All rights reserved.
+// 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.
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package resource
+package resources
 
 import (
 	"fmt"
@@ -24,6 +24,8 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/gohugoio/hugo/media"
+
 	"github.com/gohugoio/hugo/output"
 	"github.com/gohugoio/hugo/tpl"
 	"github.com/pkg/errors"
@@ -32,35 +34,28 @@ import (
 	"github.com/gohugoio/hugo/common/collections"
 	"github.com/gohugoio/hugo/common/hugio"
 	"github.com/gohugoio/hugo/common/loggers"
+	"github.com/gohugoio/hugo/resources/resource"
 
 	"github.com/spf13/afero"
 
-	"github.com/gobwas/glob"
 	"github.com/gohugoio/hugo/helpers"
-	"github.com/gohugoio/hugo/media"
 	"github.com/gohugoio/hugo/source"
 )
 
 var (
-	_ ContentResource         = (*genericResource)(nil)
-	_ ReadSeekCloserResource  = (*genericResource)(nil)
-	_ Resource                = (*genericResource)(nil)
-	_ Source                  = (*genericResource)(nil)
-	_ Cloner                  = (*genericResource)(nil)
-	_ ResourcesLanguageMerger = (*Resources)(nil)
-	_ permalinker             = (*genericResource)(nil)
-	_ collections.Slicer      = (*genericResource)(nil)
-	_ Identifier              = (*genericResource)(nil)
+	_ resource.ContentResource         = (*genericResource)(nil)
+	_ resource.ReadSeekCloserResource  = (*genericResource)(nil)
+	_ resource.Resource                = (*genericResource)(nil)
+	_ resource.Source                  = (*genericResource)(nil)
+	_ resource.Cloner                  = (*genericResource)(nil)
+	_ resource.ResourcesLanguageMerger = (*resource.Resources)(nil)
+	_ permalinker                      = (*genericResource)(nil)
+	_ collections.Slicer               = (*genericResource)(nil)
+	_ resource.Identifier              = (*genericResource)(nil)
 )
 
 var noData = make(map[string]interface{})
 
-// Source is an internal template and not meant for use in the templates. It
-// may change without notice.
-type Source interface {
-	Publish() error
-}
-
 type permalinker interface {
 	relPermalinkFor(target string) string
 	permalinkFor(target string) string
@@ -69,215 +64,6 @@ type permalinker interface {
 	targetPath() string
 }
 
-// Cloner is an internal template and not meant for use in the templates. It
-// may change without notice.
-type Cloner interface {
-	WithNewBase(base string) Resource
-}
-
-// Resource represents a linkable resource, i.e. a content page, image etc.
-type Resource interface {
-	resourceBase
-
-	// Permalink represents the absolute link to this resource.
-	Permalink() string
-
-	// RelPermalink represents the host relative link to this resource.
-	RelPermalink() string
-
-	// 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
-
-	// 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
-
-	// Resource specific data set by Hugo.
-	// One example would be.Data.Digest for fingerprinted resources.
-	Data() interface{}
-
-	// Params set in front matter for this resource.
-	Params() map[string]interface{}
-}
-
-// resourceBase pulls out the minimal set of operations to define a Resource,
-// to simplify testing etc.
-type resourceBase interface {
-	// MediaType is this resource's MIME type.
-	MediaType() media.Type
-}
-
-// 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)
-}
-
-type translatedResource interface {
-	TranslationKey() string
-}
-
-// 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.
-// 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 ContentResource interface {
-	resourceBase
-
-	// 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 {
-	resourceBase
-	ReadSeekCloser() (hugio.ReadSeekCloser, error)
-}
-
-// Resources represents a slice of resources, which can be a mix of different types.
-// I.e. both pages and images etc.
-type Resources []Resource
-
-// ResourcesConverter converts a given slice of Resource objects to Resources.
-type ResourcesConverter interface {
-	ToResources() Resources
-}
-
-// ByType returns resources of a given resource type (ie. "image").
-func (r Resources) ByType(tp string) Resources {
-	var filtered Resources
-
-	for _, resource := range r {
-		if resource.ResourceType() == tp {
-			filtered = append(filtered, resource)
-		}
-	}
-	return filtered
-}
-
-// GetMatch finds the first Resource matching the given pattern, or nil if none found.
-// See Match for a more complete explanation about the rules used.
-func (r Resources) GetMatch(pattern string) Resource {
-	g, err := getGlob(pattern)
-	if err != nil {
-		return nil
-	}
-
-	for _, resource := range r {
-		if g.Match(strings.ToLower(resource.Name())) {
-			return resource
-		}
-	}
-
-	return nil
-}
-
-// Match gets all resources matching the given base filename prefix, e.g
-// "*.png" will match all png files. The "*" does not match path delimiters (/),
-// so if you organize your resources in sub-folders, you need to be explicit about it, e.g.:
-// "images/*.png". To match any PNG image anywhere in the bundle you can do "**.png", and
-// to match all PNG images below the images folder, use "images/**.jpg".
-// The matching is case insensitive.
-// Match matches by using the value of Resource.Name, which, by default, is a filename with
-// path relative to the bundle root with Unix style slashes (/) and no leading slash, e.g. "images/logo.png".
-// See https://github.com/gobwas/glob for the full rules set.
-func (r Resources) Match(pattern string) Resources {
-	g, err := getGlob(pattern)
-	if err != nil