jellyfin/MediaBrowser.Providers/Plugins/MusicBrainz/AlbumProvider.cs
2020-08-25 13:03:07 +02:00

790 lines
30 KiB
C#

#pragma warning disable CS1591
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Xml;
using MediaBrowser.Common;
using MediaBrowser.Controller.Entities.Audio;
using MediaBrowser.Controller.Providers;
using MediaBrowser.Model.Entities;
using MediaBrowser.Model.Providers;
using MediaBrowser.Providers.Plugins.MusicBrainz;
using Microsoft.Extensions.Logging;
namespace MediaBrowser.Providers.Music
{
public class MusicBrainzAlbumProvider : IRemoteMetadataProvider<MusicAlbum, AlbumInfo>, IHasOrder
{
/// <summary>
/// The Jellyfin user-agent is unrestricted but source IP must not exceed
/// one request per second, therefore we rate limit to avoid throttling.
/// Be prudent, use a value slightly above the minimun required.
/// https://musicbrainz.org/doc/XML_Web_Service/Rate_Limiting
/// </summary>
private readonly long _musicBrainzQueryIntervalMs;
/// <summary>
/// For each single MB lookup/search, this is the maximum number of
/// attempts that shall be made whilst receiving a 503 Server
/// Unavailable (indicating throttled) response.
/// </summary>
private const uint MusicBrainzQueryAttempts = 5u;
internal static MusicBrainzAlbumProvider Current;
private readonly IHttpClientFactory _httpClientFactory;
private readonly IApplicationHost _appHost;
private readonly ILogger<MusicBrainzAlbumProvider> _logger;
private readonly string _musicBrainzBaseUrl;
private Stopwatch _stopWatchMusicBrainz = new Stopwatch();
public MusicBrainzAlbumProvider(
IHttpClientFactory httpClientFactory,
IApplicationHost appHost,
ILogger<MusicBrainzAlbumProvider> logger)
{
_httpClientFactory = httpClientFactory;
_appHost = appHost;
_logger = logger;
_musicBrainzBaseUrl = Plugin.Instance.Configuration.Server;
_musicBrainzQueryIntervalMs = Plugin.Instance.Configuration.RateLimit;
// Use a stopwatch to ensure we don't exceed the MusicBrainz rate limit
_stopWatchMusicBrainz.Start();
Current = this;
}
/// <inheritdoc />
public string Name => "MusicBrainz";
/// <inheritdoc />
public int Order => 0;
/// <inheritdoc />
public async Task<IEnumerable<RemoteSearchResult>> GetSearchResults(AlbumInfo searchInfo, CancellationToken cancellationToken)
{
// TODO maybe remove when artist metadata can be disabled
if (!Plugin.Instance.Configuration.Enable)
{
return Enumerable.Empty<RemoteSearchResult>();
}
var releaseId = searchInfo.GetReleaseId();
var releaseGroupId = searchInfo.GetReleaseGroupId();
string url;
if (!string.IsNullOrEmpty(releaseId))
{
url = "/ws/2/release/?query=reid:" + releaseId.ToString(CultureInfo.InvariantCulture);
}
else if (!string.IsNullOrEmpty(releaseGroupId))
{
url = "/ws/2/release?release-group=" + releaseGroupId.ToString(CultureInfo.InvariantCulture);
}
else
{
var artistMusicBrainzId = searchInfo.GetMusicBrainzArtistId();
if (!string.IsNullOrWhiteSpace(artistMusicBrainzId))
{
url = string.Format(
CultureInfo.InvariantCulture,
"/ws/2/release/?query=\"{0}\" AND arid:{1}",
WebUtility.UrlEncode(searchInfo.Name),
artistMusicBrainzId);
}
else
{
// I'm sure there is a better way but for now it resolves search for 12" Mixes
var queryName = searchInfo.Name.Replace("\"", string.Empty);
url = string.Format(
CultureInfo.InvariantCulture,
"/ws/2/release/?query=\"{0}\" AND artist:\"{1}\"",
WebUtility.UrlEncode(queryName),
WebUtility.UrlEncode(searchInfo.GetAlbumArtist()));
}
}
if (!string.IsNullOrWhiteSpace(url))
{
using var response = await GetMusicBrainzResponse(url, cancellationToken).ConfigureAwait(false);
await using var stream = await response.Content.ReadAsStreamAsync().ConfigureAwait(false);
return GetResultsFromResponse(stream);
}
return Enumerable.Empty<RemoteSearchResult>();
}
private IEnumerable<RemoteSearchResult> GetResultsFromResponse(Stream stream)
{
using (var oReader = new StreamReader(stream, Encoding.UTF8))
{
var settings = new XmlReaderSettings()
{
ValidationType = ValidationType.None,
CheckCharacters = false,
IgnoreProcessingInstructions = true,
IgnoreComments = true
};
using (var reader = XmlReader.Create(oReader, settings))
{
var results = ReleaseResult.Parse(reader);
return results.Select(i =>
{
var result = new RemoteSearchResult
{
Name = i.Title,
ProductionYear = i.Year
};
if (i.Artists.Count > 0)
{
result.AlbumArtist = new RemoteSearchResult
{
SearchProviderName = Name,
Name = i.Artists[0].Item1
};
result.AlbumArtist.SetProviderId(MetadataProvider.MusicBrainzArtist, i.Artists[0].Item2);
}
if (!string.IsNullOrWhiteSpace(i.ReleaseId))
{
result.SetProviderId(MetadataProvider.MusicBrainzAlbum, i.ReleaseId);
}
if (!string.IsNullOrWhiteSpace(i.ReleaseGroupId))
{
result.SetProviderId(MetadataProvider.MusicBrainzReleaseGroup, i.ReleaseGroupId);
}
return result;
});
}
}
}
/// <inheritdoc />
public async Task<MetadataResult<MusicAlbum>> GetMetadata(AlbumInfo id, CancellationToken cancellationToken)
{
var releaseId = id.GetReleaseId();
var releaseGroupId = id.GetReleaseGroupId();
var result = new MetadataResult<MusicAlbum>
{
Item = new MusicAlbum()
};
// TODO maybe remove when artist metadata can be disabled
if (!Plugin.Instance.Configuration.Enable)
{
return result;
}
// If we have a release group Id but not a release Id...
if (string.IsNullOrWhiteSpace(releaseId) && !string.IsNullOrWhiteSpace(releaseGroupId))
{
releaseId = await GetReleaseIdFromReleaseGroupId(releaseGroupId, cancellationToken).ConfigureAwait(false);
result.HasMetadata = true;
}
if (string.IsNullOrWhiteSpace(releaseId))
{
var artistMusicBrainzId = id.GetMusicBrainzArtistId();
var releaseResult = await GetReleaseResult(artistMusicBrainzId, id.GetAlbumArtist(), id.Name, cancellationToken).ConfigureAwait(false);
if (releaseResult != null)
{
if (!string.IsNullOrWhiteSpace(releaseResult.ReleaseId))
{
releaseId = releaseResult.ReleaseId;
result.HasMetadata = true;
}
if (!string.IsNullOrWhiteSpace(releaseResult.ReleaseGroupId))
{
releaseGroupId = releaseResult.ReleaseGroupId;
result.HasMetadata = true;
}
result.Item.ProductionYear = releaseResult.Year;
result.Item.Overview = releaseResult.Overview;
}
}
// If we have a release Id but not a release group Id...
if (!string.IsNullOrWhiteSpace(releaseId) && string.IsNullOrWhiteSpace(releaseGroupId))
{
releaseGroupId = await GetReleaseGroupFromReleaseId(releaseId, cancellationToken).ConfigureAwait(false);
result.HasMetadata = true;
}
if (!string.IsNullOrWhiteSpace(releaseId) || !string.IsNullOrWhiteSpace(releaseGroupId))
{
result.HasMetadata = true;
}
if (result.HasMetadata)
{
if (!string.IsNullOrEmpty(releaseId))
{
result.Item.SetProviderId(MetadataProvider.MusicBrainzAlbum, releaseId);
}
if (!string.IsNullOrEmpty(releaseGroupId))
{
result.Item.SetProviderId(MetadataProvider.MusicBrainzReleaseGroup, releaseGroupId);
}
}
return result;
}
private Task<ReleaseResult> GetReleaseResult(string artistMusicBrainId, string artistName, string albumName, CancellationToken cancellationToken)
{
if (!string.IsNullOrEmpty(artistMusicBrainId))
{
return GetReleaseResult(albumName, artistMusicBrainId, cancellationToken);
}
if (string.IsNullOrWhiteSpace(artistName))
{
return Task.FromResult(new ReleaseResult());
}
return GetReleaseResultByArtistName(albumName, artistName, cancellationToken);
}
private async Task<ReleaseResult> GetReleaseResult(string albumName, string artistId, CancellationToken cancellationToken)
{
var url = string.Format(CultureInfo.InvariantCulture, "/ws/2/release/?query=\"{0}\" AND arid:{1}",
WebUtility.UrlEncode(albumName),
artistId);
using var response = await GetMusicBrainzResponse(url, cancellationToken).ConfigureAwait(false);
await using var stream = await response.Content.ReadAsStreamAsync().ConfigureAwait(false);
using var oReader = new StreamReader(stream, Encoding.UTF8);
var settings = new XmlReaderSettings
{
ValidationType = ValidationType.None,
CheckCharacters = false,
IgnoreProcessingInstructions = true,
IgnoreComments = true
};
using var reader = XmlReader.Create(oReader, settings);
return ReleaseResult.Parse(reader).FirstOrDefault();
}
private async Task<ReleaseResult> GetReleaseResultByArtistName(string albumName, string artistName, CancellationToken cancellationToken)
{
var url = string.Format(
CultureInfo.InvariantCulture,
"/ws/2/release/?query=\"{0}\" AND artist:\"{1}\"",
WebUtility.UrlEncode(albumName),
WebUtility.UrlEncode(artistName));
using var response = await GetMusicBrainzResponse(url, cancellationToken).ConfigureAwait(false);
await using var stream = await response.Content.ReadAsStreamAsync().ConfigureAwait(false);
using var oReader = new StreamReader(stream, Encoding.UTF8);
var settings = new XmlReaderSettings()
{
ValidationType = ValidationType.None,
CheckCharacters = false,
IgnoreProcessingInstructions = true,
IgnoreComments = true
};
using var reader = XmlReader.Create(oReader, settings);
return ReleaseResult.Parse(reader).FirstOrDefault();
}
private class ReleaseResult
{
public string ReleaseId;
public string ReleaseGroupId;
public string Title;
public string Overview;
public int? Year;
public List<ValueTuple<string, string>> Artists = new List<ValueTuple<string, string>>();
public static IEnumerable<ReleaseResult> Parse(XmlReader reader)
{
reader.MoveToContent();
reader.Read();
// Loop through each element
while (!reader.EOF && reader.ReadState == ReadState.Interactive)
{
if (reader.NodeType == XmlNodeType.Element)
{
switch (reader.Name)
{
case "release-list":
{
if (reader.IsEmptyElement)
{
reader.Read();
continue;
}
using (var subReader = reader.ReadSubtree())
{
return ParseReleaseList(subReader).ToList();
}
}
default:
{
reader.Skip();
break;
}
}
}
else
{
reader.Read();
}
}
return Enumerable.Empty<ReleaseResult>();
}
private static IEnumerable<ReleaseResult> ParseReleaseList(XmlReader reader)
{
reader.MoveToContent();
reader.Read();
// Loop through each element
while (!reader.EOF && reader.ReadState == ReadState.Interactive)
{
if (reader.NodeType == XmlNodeType.Element)
{
switch (reader.Name)
{
case "release":
{
if (reader.IsEmptyElement)
{
reader.Read();
continue;
}
var releaseId = reader.GetAttribute("id");
using (var subReader = reader.ReadSubtree())
{
var release = ParseRelease(subReader, releaseId);
if (release != null)
{
yield return release;
}
}
break;
}
default:
{
reader.Skip();
break;
}
}
}
else
{
reader.Read();
}
}
}
private static ReleaseResult ParseRelease(XmlReader reader, string releaseId)
{
var result = new ReleaseResult
{
ReleaseId = releaseId
};
reader.MoveToContent();
reader.Read();
// http://stackoverflow.com/questions/2299632/why-does-xmlreader-skip-every-other-element-if-there-is-no-whitespace-separator
// Loop through each element
while (!reader.EOF && reader.ReadState == ReadState.Interactive)
{
if (reader.NodeType == XmlNodeType.Element)
{
switch (reader.Name)
{
case "title":
{
result.Title = reader.ReadElementContentAsString();
break;
}
case "date":
{
var val = reader.ReadElementContentAsString();
if (DateTime.TryParse(val, out var date))
{
result.Year = date.Year;
}
break;
}
case "annotation":
{
result.Overview = reader.ReadElementContentAsString();
break;
}
case "release-group":
{
result.ReleaseGroupId = reader.GetAttribute("id");
reader.Skip();
break;
}
case "artist-credit":
{
using (var subReader = reader.ReadSubtree())
{
var artist = ParseArtistCredit(subReader);
if (!string.IsNullOrEmpty(artist.Item1))
{
result.Artists.Add(artist);
}
}
break;
}
default:
{
reader.Skip();
break;
}
}
}
else
{
reader.Read();
}
}
return result;
}
}
private static ValueTuple<string, string> ParseArtistCredit(XmlReader reader)
{
reader.MoveToContent();
reader.Read();
// http://stackoverflow.com/questions/2299632/why-does-xmlreader-skip-every-other-element-if-there-is-no-whitespace-separator
// Loop through each element
while (!reader.EOF && reader.ReadState == ReadState.Interactive)
{
if (reader.NodeType == XmlNodeType.Element)
{
switch (reader.Name)
{
case "name-credit":
{
using (var subReader = reader.ReadSubtree())
{
return ParseArtistNameCredit(subReader);
}
}
default:
{
reader.Skip();
break;
}
}
}
else
{
reader.Read();
}
}
return new ValueTuple<string, string>();
}
private static (string, string) ParseArtistNameCredit(XmlReader reader)
{
reader.MoveToContent();
reader.Read();
// http://stackoverflow.com/questions/2299632/why-does-xmlreader-skip-every-other-element-if-there-is-no-whitespace-separator
// Loop through each element
while (!reader.EOF && reader.ReadState == ReadState.Interactive)
{
if (reader.NodeType == XmlNodeType.Element)
{
switch (reader.Name)
{
case "artist":
{
var id = reader.GetAttribute("id");
using (var subReader = reader.ReadSubtree())
{
return ParseArtistArtistCredit(subReader, id);
}
}
default:
{
reader.Skip();
break;
}
}
}
else
{
reader.Read();
}
}
return (null, null);
}
private static (string name, string id) ParseArtistArtistCredit(XmlReader reader, string artistId)
{
reader.MoveToContent();
reader.Read();
string name = null;
// http://stackoverflow.com/questions/2299632/why-does-xmlreader-skip-every-other-element-if-there-is-no-whitespace-separator
// Loop through each element
while (!reader.EOF && reader.ReadState == ReadState.Interactive)
{
if (reader.NodeType == XmlNodeType.Element)
{
switch (reader.Name)
{
case "name":
{
name = reader.ReadElementContentAsString();
break;
}
default:
{
reader.Skip();
break;
}
}
}
else
{
reader.Read();
}
}
return (name, artistId);
}
private async Task<string> GetReleaseIdFromReleaseGroupId(string releaseGroupId, CancellationToken cancellationToken)
{
var url = "/ws/2/release?release-group=" + releaseGroupId.ToString(CultureInfo.InvariantCulture);
using var response = await GetMusicBrainzResponse(url, cancellationToken).ConfigureAwait(false);
await using var stream = await response.Content.ReadAsStreamAsync().ConfigureAwait(false);
using var oReader = new StreamReader(stream, Encoding.UTF8);
var settings = new XmlReaderSettings
{
ValidationType = ValidationType.None,
CheckCharacters = false,
IgnoreProcessingInstructions = true,
IgnoreComments = true
};
using var reader = XmlReader.Create(oReader, settings);
var result = ReleaseResult.Parse(reader).FirstOrDefault();
return result?.ReleaseId;
}
/// <summary>
/// Gets the release group id internal.
/// </summary>
/// <param name="releaseEntryId">The release entry id.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>Task{System.String}.</returns>
private async Task<string> GetReleaseGroupFromReleaseId(string releaseEntryId, CancellationToken cancellationToken)
{
var url = "/ws/2/release-group/?query=reid:" + releaseEntryId.ToString(CultureInfo.InvariantCulture);
using var response = await GetMusicBrainzResponse(url, cancellationToken).ConfigureAwait(false);
await using var stream = await response.Content.ReadAsStreamAsync().ConfigureAwait(false);
using var oReader = new StreamReader(stream, Encoding.UTF8);
var settings = new XmlReaderSettings
{
ValidationType = ValidationType.None,
CheckCharacters = false,
IgnoreProcessingInstructions = true,
IgnoreComments = true
};
using (var reader = XmlReader.Create(oReader, settings))
{
reader.MoveToContent();
reader.Read();
// Loop through each element
while (!reader.EOF && reader.ReadState == ReadState.Interactive)
{
if (reader.NodeType == XmlNodeType.Element)
{
switch (reader.Name)
{
case "release-group-list":
{
if (reader.IsEmptyElement)
{
reader.Read();
continue;
}
using (var subReader = reader.ReadSubtree())
{
return GetFirstReleaseGroupId(subReader);
}
}
default:
{
reader.Skip();
break;
}
}
}
else
{
reader.Read();
}
}
return null;
}
}
private string GetFirstReleaseGroupId(XmlReader reader)
{
reader.MoveToContent();
reader.Read();
// Loop through each element
while (!reader.EOF && reader.ReadState == ReadState.Interactive)
{
if (reader.NodeType == XmlNodeType.Element)
{
switch (reader.Name)
{
case "release-group":
{
return reader.GetAttribute("id");
}
default:
{
reader.Skip();
break;
}
}
}
else
{
reader.Read();
}
}
return null;
}
/// <summary>
/// Makes request to MusicBrainz server and awaits a response.
/// A 503 Service Unavailable response indicates throttling to maintain a rate limit.
/// A number of retries shall be made in order to try and satisfy the request before
/// giving up and returning null.
/// </summary>
internal async Task<HttpResponseMessage> GetMusicBrainzResponse(string url, CancellationToken cancellationToken)
{
using var options = new HttpRequestMessage(HttpMethod.Get, _musicBrainzBaseUrl.TrimEnd('/') + url);
// MusicBrainz request a contact email address is supplied, as comment, in user agent field:
// https://musicbrainz.org/doc/XML_Web_Service/Rate_Limiting#User-Agent
options.Headers.UserAgent.ParseAdd(string.Format(
CultureInfo.InvariantCulture,
"{0} ( {1} )",
_appHost.ApplicationUserAgent,
_appHost.ApplicationUserAgentAddress));
HttpResponseMessage response;
var attempts = 0u;
do
{
attempts++;
if (_stopWatchMusicBrainz.ElapsedMilliseconds < _musicBrainzQueryIntervalMs)
{
// MusicBrainz is extremely adamant about limiting to one request per second
var delayMs = _musicBrainzQueryIntervalMs - _stopWatchMusicBrainz.ElapsedMilliseconds;
await Task.Delay((int)delayMs, cancellationToken).ConfigureAwait(false);
}
// Write time since last request to debug log as evidence we're meeting rate limit
// requirement, before resetting stopwatch back to zero.
_logger.LogDebug("GetMusicBrainzResponse: Time since previous request: {0} ms", _stopWatchMusicBrainz.ElapsedMilliseconds);
_stopWatchMusicBrainz.Restart();
response = await _httpClientFactory.CreateClient().SendAsync(options).ConfigureAwait(false);
// We retry a finite number of times, and only whilst MB is indicating 503 (throttling)
}
while (attempts < MusicBrainzQueryAttempts && response.StatusCode == HttpStatusCode.ServiceUnavailable);
// Log error if unable to query MB database due to throttling
if (attempts == MusicBrainzQueryAttempts && response.StatusCode == HttpStatusCode.ServiceUnavailable)
{
_logger.LogError("GetMusicBrainzResponse: 503 Service Unavailable (throttled) response received {0} times whilst requesting {1}", attempts, options.RequestUri);
}
return response;
}
/// <inheritdoc />
public Task<HttpResponseMessage> GetImageResponse(string url, CancellationToken cancellationToken)
{
throw new NotImplementedException();
}
}
}