Move internal packages to an internal folder

For reference: https://go.dev/doc/go1.4#internalpackages

internal/reader/rdf/rdf.go

@@ -0,0 +1,119 @@
+// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package rdf // import "miniflux.app/v2/internal/reader/rdf"
+
+import (
+	"encoding/xml"
+	"html"
+	"strings"
+	"time"
+
+	"miniflux.app/v2/internal/crypto"
+	"miniflux.app/v2/internal/logger"
+	"miniflux.app/v2/internal/model"
+	"miniflux.app/v2/internal/reader/date"
+	"miniflux.app/v2/internal/reader/sanitizer"
+	"miniflux.app/v2/internal/url"
+)
+
+type rdfFeed struct {
+	XMLName xml.Name  `xml:"RDF"`
+	Title   string    `xml:"channel>title"`
+	Link    string    `xml:"channel>link"`
+	Items   []rdfItem `xml:"item"`
+	DublinCoreFeedElement
+}
+
+func (r *rdfFeed) Transform(baseURL string) *model.Feed {
+	var err error
+	feed := new(model.Feed)
+	feed.Title = sanitizer.StripTags(r.Title)
+	feed.FeedURL = baseURL
+	feed.SiteURL, err = url.AbsoluteURL(baseURL, r.Link)
+	if err != nil {
+		feed.SiteURL = r.Link
+	}
+
+	for _, item := range r.Items {
+		entry := item.Transform()
+		if entry.Author == "" && r.DublinCoreCreator != "" {
+			entry.Author = strings.TrimSpace(r.DublinCoreCreator)
+		}
+
+		if entry.URL == "" {
+			entry.URL = feed.SiteURL
+		} else {
+			entryURL, err := url.AbsoluteURL(feed.SiteURL, entry.URL)
+			if err == nil {
+				entry.URL = entryURL
+			}
+		}
+
+		feed.Entries = append(feed.Entries, entry)
+	}
+
+	return feed
+}
+
+type rdfItem struct {
+	Title       string `xml:"title"`
+	Link        string `xml:"link"`
+	Description string `xml:"description"`
+	DublinCoreEntryElement
+}
+
+func (r *rdfItem) Transform() *model.Entry {
+	entry := new(model.Entry)
+	entry.Title = r.entryTitle()
+	entry.Author = r.entryAuthor()
+	entry.URL = r.entryURL()
+	entry.Content = r.entryContent()
+	entry.Hash = r.entryHash()
+	entry.Date = r.entryDate()
+	return entry
+}
+
+func (r *rdfItem) entryTitle() string {
+	return html.UnescapeString(strings.TrimSpace(r.Title))
+}
+
+func (r *rdfItem) entryContent() string {
+	switch {
+	case r.DublinCoreContent != "":
+		return r.DublinCoreContent
+	default:
+		return r.Description
+	}
+}
+
+func (r *rdfItem) entryAuthor() string {
+	return strings.TrimSpace(r.DublinCoreCreator)
+}
+
+func (r *rdfItem) entryURL() string {
+	return strings.TrimSpace(r.Link)
+}
+
+func (r *rdfItem) entryDate() time.Time {
+	if r.DublinCoreDate != "" {
+		result, err := date.Parse(r.DublinCoreDate)
+		if err != nil {
+			logger.Error("rdf: %v (entry link = %s)", err, r.Link)
+			return time.Now()
+		}
+
+		return result
+	}
+
+	return time.Now()
+}
+
+func (r *rdfItem) entryHash() string {
+	value := r.Link
+	if value == "" {
+		value = r.Title + r.Description
+	}
+
+	return crypto.Hash(value)
+}