OPDS Support (#526)

* Added some basic OPDS implementation

* Fixed an issue with feed href

* More changes

* Added library routes and moved user code to a method so we can hack in fixed code without authentication

* Images now load on the OPDS reusing our existing Image infrastructure.

* Added the ability to download and moved some download code to a dedicated service

* Download is working, pagination is implemented.

* Refactored libraries to use pagination

* Laid foundation for OpenSearch implementation

* Fixed up some serialization issues and some old code that wasn't referencing helper methods

* Ensure chapters are sorted when we send them over OPDS

* OpenSearch implemented

* Removed any support for OPDS-PS due to lack of apps supporting it.

* Don't distribute development.json nor stats directory on build.

* Implemented In Progress feed as well.

* Ability to enable OPDS for server. OPDS now accepts initial call as POST in case app uses username/password.

* UI now properly renders state for OPDS enablement. Added Collections routes.

* Fixed pagination startIndex on OPDS feeds when there is less than 1 page.

* Chunky Reader now works. It only accepts UTF-8 encodings

* More Chunky fixes

* More chunky changes, such a fussy client.

* Implemented the ability to have a custom api key assigned to a user and use that api key as your authentication token against OPDS routing.

* Implemented the ability to reset your API Key

* Fixed favicon not being sent back correctly

* Fixed an issue where images wouldn't send on OPDS feed.

* Implemented Page streaming and fixed a pagination bug

* Hooked in the ability to save progress in Kavita when Page Streaming

API/DTOs/OPDS/Author.cs

@@ -0,0 +1,12 @@
+using System.Xml.Serialization;
+
+namespace API.DTOs.OPDS
+{
+    public class Author
+    {
+        [XmlElement("name")]
+        public string Name { get; set; }
+        [XmlElement("uri")]
+        public string Uri { get; set; }
+    }
+}

API/DTOs/OPDS/Feed.cs

@@ -0,0 +1,62 @@
+using System;
+using System.Collections.Generic;
+using System.Xml.Serialization;
+
+namespace API.DTOs.OPDS
+{
+    /// <summary>
+    ///
+    /// </summary>
+    [XmlRoot("feed", Namespace = "http://www.w3.org/2005/Atom")]
+    public class Feed
+    {
+        [XmlElement("updated")]
+        public string Updated { get; init; } = DateTime.UtcNow.ToString("s");
+
+        [XmlElement("id")]
+        public string Id { get; set; }
+
+        [XmlElement("title")]
+        public string Title { get; set; }
+
+        [XmlElement("icon")]
+        public string Icon { get; set; } = "/favicon.ico";
+
+        [XmlElement("author")]
+        public Author Author { get; set; } = new Author()
+        {
+            Name = "Kavita",
+            Uri = "https://kavitareader.com"
+        };
+
+        [XmlElement("totalResults", Namespace = "http://a9.com/-/spec/opensearch/1.1/")]
+        public int? Total { get; set; } = null;
+
+        [XmlElement("itemsPerPage", Namespace = "http://a9.com/-/spec/opensearch/1.1/")]
+        public int? ItemsPerPage { get; set; } = null;
+
+        [XmlElement("startIndex", Namespace = "http://a9.com/-/spec/opensearch/1.1/")]
+        public int? StartIndex { get; set; } = null;
+
+        [XmlElement("link")]
+        public List<FeedLink> Links { get; set; } = new List<FeedLink>() ;
+
+        [XmlElement("entry")]
+        public List<FeedEntry> Entries { get; set; } = new List<FeedEntry>();
+
+        public bool ShouldSerializeTotal()
+        {
+            return Total.HasValue;
+        }
+
+        public bool ShouldSerializeItemsPerPage()
+        {
+            return ItemsPerPage.HasValue;
+        }
+
+        public bool ShouldSerializeStartIndex()
+        {
+            return StartIndex.HasValue;
+        }
+    }
+}

API/DTOs/OPDS/FeedEntry.cs

@@ -0,0 +1,51 @@
+using System;
+using System.Collections.Generic;
+using System.Xml.Serialization;
+
+namespace API.DTOs.OPDS
+{
+    public class FeedEntry
+    {
+        [XmlElement("updated")]
+        public string Updated { get; init; } = DateTime.UtcNow.ToString("s");
+
+        [XmlElement("id")]
+        public string Id { get; set; }
+
+        [XmlElement("title")]
+        public string Title { get; set; }
+
+        [XmlElement("summary")]
+        public string Summary { get; set; }
+
+        /// <summary>
+        /// Represents Size of the Entry
+        /// Tag: , ElementName = "dcterms:extent"
+        /// <example>2 MB</example>
+        /// </summary>
+        [XmlElement("extent", Namespace = "http://purl.org/dc/terms/")]
+        public string Extent { get; set; }
+
+        /// <summary>
+        /// Format of the file
+        /// https://dublincore.org/specifications/dublin-core/dcmi-terms/
+        /// </summary>
+        [XmlElement("format", Namespace = "http://purl.org/dc/terms/format")]
+        public string Format { get; set; }
+
+        [XmlElement("language", Namespace = "http://purl.org/dc/terms/")]
+        public string Language { get; set; }
+
+        [XmlElement("content")]
+        public FeedEntryContent Content { get; set; }
+
+        [XmlElement("link")]
+        public List<FeedLink> Links = new List<FeedLink>();
+
+        // [XmlElement("author")]
+        // public List<FeedAuthor> Authors = new List<FeedAuthor>();
+
+        // [XmlElement("category")]
+        // public List<FeedCategory> Categories = new List<FeedCategory>();
+    }
+}

API/DTOs/OPDS/FeedEntryContent.cs

@@ -0,0 +1,12 @@
+using System.Xml.Serialization;
+
+namespace API.DTOs.OPDS
+{
+    public class FeedEntryContent
+    {
+        [XmlAttribute("type")]
+        public string Type = "text";
+        [XmlText]
+        public string Text;
+    }
+}

API/DTOs/OPDS/FeedLink.cs

@@ -0,0 +1,33 @@
+using System.Xml.Serialization;
+
+namespace API.DTOs.OPDS
+{
+    public class FeedLink
+    {
+        /// <summary>
+        /// Relation on the Link
+        /// </summary>
+        [XmlAttribute("rel")]
+        public string Rel { get; set; }
+
+        /// <summary>
+        /// Should be any of the types here <see cref="FeedLinkType"/>
+        /// </summary>
+        [XmlAttribute("type")]
+        public string Type { get; set; }
+
+        [XmlAttribute("href")]
+        public string Href { get; set; }
+
+        [XmlAttribute("title")]
+        public string Title { get; set; }
+
+        [XmlAttribute("count", Namespace = "http://vaemendis.net/opds-pse/ns")]
+        public int TotalPages { get; set; } = 0;
+
+        public bool ShouldSerializeTotalPages()
+        {
+            return TotalPages > 0;
+        }
+    }
+}

API/DTOs/OPDS/FeedLinkRelation.cs

@@ -0,0 +1,24 @@
+namespace API.DTOs.OPDS
+{
+    public static class FeedLinkRelation
+    {
+        public const string Debug = "debug";
+        public const string Search = "search";
+        public const string Self = "self";
+        public const string Start = "start";
+        public const string Next = "next";
+        public const string Prev = "prev";
+        public const string Alternate = "alternate";
+        public const string SubSection = "subsection";
+        public const string Related = "related";
+        public const string Image = "http://opds-spec.org/image";
+        public const string Thumbnail = "http://opds-spec.org/image/thumbnail";
+        /// <summary>
+        /// This will allow for a download to occur
+        /// </summary>
+        public const string Acquisition = "http://opds-spec.org/acquisition/open-access";
+#pragma warning disable S1075
+        public const string Stream = "http://vaemendis.net/opds-pse/stream";
+#pragma warning restore S1075
+    }
+}

API/DTOs/OPDS/FeedLinkType.cs

@@ -0,0 +1,11 @@
+namespace API.DTOs.OPDS
+{
+    public static class FeedLinkType
+    {
+        public const string Atom = "application/atom+xml";
+        public const string AtomSearch = "application/opensearchdescription+xml";
+        public const string AtomNavigation = "application/atom+xml;profile=opds-catalog;kind=navigation";
+        public const string AtomAcquisition = "application/atom+xml;profile=opds-catalog;kind=acquisition";
+        public const string Image = "image/jpeg";
+    }
+}

API/DTOs/OPDS/OpenSearchDescription.cs

@@ -0,0 +1,42 @@
+using System.Xml.Serialization;
+
+namespace API.DTOs.OPDS
+{
+    [XmlRoot("OpenSearchDescription", Namespace = "http://a9.com/-/spec/opensearch/1.1/")]
+    public class OpenSearchDescription
+    {
+        /// <summary>
+        /// Contains a brief human-readable title that identifies this search engine.
+        /// </summary>
+        public string ShortName { get; set; }
+        /// <summary>
+        /// Contains an extended human-readable title that identifies this search engine.
+        /// </summary>
+        public string LongName { get; set; }
+        /// <summary>
+        /// Contains a human-readable text description of the search engine.
+        /// </summary>
+        public string Description { get; set; }
+        /// <summary>
+        /// https://github.com/dewitt/opensearch/blob/master/opensearch-1-1-draft-6.md#the-url-element
+        /// </summary>
+        public SearchLink Url { get; set; }
+        /// <summary>
+        /// Contains a set of words that are used as keywords to identify and categorize this search content.
+        /// Tags must be a single word and are delimited by the space character (' ').
+        /// </summary>
+        public string Tags { get; set; }
+        /// <summary>
+        /// Contains a URL that identifies the location of an image that can be used in association with this search content.
+        /// <example><Image height="64" width="64" type="image/png">http://example.com/websearch.png</Image></example>
+        /// </summary>
+        public string Image { get; set; }
+        public string InputEncoding { get; set; } = "UTF-8";
+        public string OutputEncoding { get; set; } = "UTF-8";
+        /// <summary>
+        /// Contains the human-readable name or identifier of the creator or maintainer of the description document.
+        /// </summary>
+        public string Developer { get; set; } = "kavitareader.com";
+
+    }
+}

API/DTOs/OPDS/SearchLink.cs

@@ -0,0 +1,16 @@
+using System.Xml.Serialization;
+
+namespace API.DTOs.OPDS
+{
+    public class SearchLink
+    {
+        [XmlAttribute("type")]
+        public string Type { get; set; }
+
+        [XmlAttribute("rel")]
+        public string Rel { get; set; } = "results";
+
+        [XmlAttribute("template")]
+        public string Template { get; set; }
+    }
+}