Add support of media elements for Atom feeds

reader/media/media.go

@@ -0,0 +1,176 @@
+// Copyright 2019 Frédéric Guillot. All rights reserved.
+// Use of this source code is governed by the Apache 2.0
+// license that can be found in the LICENSE file.
+
+package media // import "miniflux.app/reader/media"
+
+import (
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+var textLinkRegex = regexp.MustCompile(`(?mi)(\bhttps?:\/\/[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])`)
+
+// Element represents XML media elements.
+type Element struct {
+	MediaGroups       []Group         `xml:"http://search.yahoo.com/mrss/ group"`
+	MediaContents     []Content       `xml:"http://search.yahoo.com/mrss/ content"`
+	MediaThumbnails   []Thumbnail     `xml:"http://search.yahoo.com/mrss/ thumbnail"`
+	MediaDescriptions DescriptionList `xml:"http://search.yahoo.com/mrss/ description"`
+	MediaPeerLinks    []PeerLink      `xml:"http://search.yahoo.com/mrss/ peerLink"`
+}
+
+// AllMediaThumbnails returns all thumbnail elements merged together.
+func (e *Element) AllMediaThumbnails() []Thumbnail {
+	var items []Thumbnail
+	items = append(items, e.MediaThumbnails...)
+	for _, mediaGroup := range e.MediaGroups {
+		items = append(items, mediaGroup.MediaThumbnails...)
+	}
+	return items
+}
+
+// AllMediaContents returns all content elements merged together.
+func (e *Element) AllMediaContents() []Content {
+	var items []Content
+	items = append(items, e.MediaContents...)
+	for _, mediaGroup := range e.MediaGroups {
+		items = append(items, mediaGroup.MediaContents...)
+	}
+	return items
+}
+
+// AllMediaPeerLinks returns all peer link elements merged together.
+func (e *Element) AllMediaPeerLinks() []PeerLink {
+	var items []PeerLink
+	items = append(items, e.MediaPeerLinks...)
+	for _, mediaGroup := range e.MediaGroups {
+		items = append(items, mediaGroup.MediaPeerLinks...)
+	}
+	return items
+}
+
+// FirstMediaDescription returns the first description element.
+func (e *Element) FirstMediaDescription() string {
+	description := e.MediaDescriptions.First()
+	if description != "" {
+		return description
+	}
+
+	for _, mediaGroup := range e.MediaGroups {
+		description = mediaGroup.MediaDescriptions.First()
+		if description != "" {
+			return description
+		}
+	}
+
+	return ""
+}
+
+// Group represents a XML element "media:group".
+type Group struct {
+	MediaContents     []Content       `xml:"http://search.yahoo.com/mrss/ content"`
+	MediaThumbnails   []Thumbnail     `xml:"http://search.yahoo.com/mrss/ thumbnail"`
+	MediaDescriptions DescriptionList `xml:"http://search.yahoo.com/mrss/ description"`
+	MediaPeerLinks    []PeerLink      `xml:"http://search.yahoo.com/mrss/ peerLink"`
+}
+
+// Content represents a XML element "media:content".
+type Content struct {
+	URL      string `xml:"url,attr"`
+	Type     string `xml:"type,attr"`
+	FileSize string `xml:"fileSize,attr"`
+	Medium   string `xml:"medium,attr"`
+}
+
+// MimeType returns the attachment mime type.
+func (mc *Content) MimeType() string {
+	switch {
+	case mc.Type == "" && mc.Medium == "image":
+		return "image/*"
+	case mc.Type == "" && mc.Medium == "video":
+		return "video/*"
+	case mc.Type == "" && mc.Medium == "audio":
+		return "audio/*"
+	case mc.Type == "" && mc.Medium == "video":
+		return "video/*"
+	case mc.Type != "":
+		return mc.Type
+	default:
+		return "application/octet-stream"
+	}
+}
+
+// Size returns the attachment size.
+func (mc *Content) Size() int64 {
+	if mc.FileSize == "" {
+		return 0
+	}
+	size, _ := strconv.ParseInt(mc.FileSize, 10, 0)
+	return size
+}
+
+// Thumbnail represents a XML element "media:thumbnail".
+type Thumbnail struct {
+	URL string `xml:"url,attr"`
+}
+
+// MimeType returns the attachment mime type.
+func (t *Thumbnail) MimeType() string {
+	return "image/*"
+}
+
+// Size returns the attachment size.
+func (t *Thumbnail) Size() int64 {
+	return 0
+}
+
+// PeerLink represents a XML element "media:peerLink".
+type PeerLink struct {
+	URL  string `xml:"href,attr"`
+	Type string `xml:"type,attr"`
+}
+
+// MimeType returns the attachment mime type.
+func (p *PeerLink) MimeType() string {
+	if p.Type != "" {
+		return p.Type
+	}
+	return "application/octet-stream"
+}
+
+// Size returns the attachment size.
+func (p *PeerLink) Size() int64 {
+	return 0
+}
+
+// Description represents a XML element "media:description".
+type Description struct {
+	Type        string `xml:"type,attr"`
+	Description string `xml:",chardata"`
+}
+
+// HTML returns the description as HTML.
+func (d *Description) HTML() string {
+	if d.Type == "html" {
+		return d.Description
+	}
+
+	content := strings.Replace(d.Description, "\n", "<br>", -1)
+	return textLinkRegex.ReplaceAllString(content, `<a href="${1}">${1}</a>`)
+}
+
+// DescriptionList represents a list of "media:description" XML elements.
+type DescriptionList []Description
+
+// First returns the first non-empty description.
+func (dl DescriptionList) First() string {
+	for _, description := range dl {
+		contents := description.HTML()
+		if contents != "" {
+			return contents
+		}
+	}
+	return ""
+}