jellyfin/MediaBrowser.Common/Plugins/BasePlugin.cs
2020-12-15 00:42:59 +00:00

339 lines
12 KiB
C#

#pragma warning disable SA1402
using System;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
using MediaBrowser.Common.Configuration;
using MediaBrowser.Model.Plugins;
using MediaBrowser.Model.Serialization;
namespace MediaBrowser.Common.Plugins
{
/// <summary>
/// Provides a common base class for all plugins.
/// </summary>
public abstract class BasePlugin : IPlugin, IPluginAssembly
{
/// <summary>
/// Gets the name of the plugin.
/// </summary>
/// <value>The name.</value>
public abstract string Name { get; }
/// <summary>
/// Gets the description.
/// </summary>
/// <value>The description.</value>
public virtual string Description => string.Empty;
/// <summary>
/// Gets the unique id.
/// </summary>
/// <value>The unique id.</value>
public virtual Guid Id { get; private set; }
/// <summary>
/// Gets the plugin version.
/// </summary>
/// <value>The version.</value>
public Version Version { get; private set; }
/// <summary>
/// Gets the path to the assembly file.
/// </summary>
/// <value>The assembly file path.</value>
public string AssemblyFilePath { get; private set; }
/// <summary>
/// Gets the full path to the data folder, where the plugin can store any miscellaneous files needed.
/// </summary>
/// <value>The data folder path.</value>
public string DataFolderPath { get; private set; }
/// <summary>
/// Gets a value indicating whether the plugin can be uninstalled.
/// </summary>
public bool CanUninstall => !Path.GetDirectoryName(AssemblyFilePath)
.Equals(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), StringComparison.InvariantCulture);
/// <summary>
/// Gets the plugin info.
/// </summary>
/// <returns>PluginInfo.</returns>
public virtual PluginInfo GetPluginInfo()
{
var info = new PluginInfo(
Name,
Version,
Description,
Id,
CanUninstall);
return info;
}
/// <summary>
/// Called just before the plugin is uninstalled from the server.
/// </summary>
public virtual void OnUninstalling()
{
}
/// <inheritdoc />
public void SetAttributes(string assemblyFilePath, string dataFolderPath, Version assemblyVersion)
{
AssemblyFilePath = assemblyFilePath;
DataFolderPath = dataFolderPath;
Version = assemblyVersion;
}
/// <inheritdoc />
public void SetId(Guid assemblyId)
{
Id = assemblyId;
}
}
/// <summary>
/// Provides a common base class for all plugins.
/// </summary>
/// <typeparam name="TConfigurationType">The type of the T configuration type.</typeparam>
public abstract class BasePlugin<TConfigurationType> : BasePlugin, IHasPluginConfiguration
where TConfigurationType : BasePluginConfiguration
{
/// <summary>
/// The configuration sync lock.
/// </summary>
private readonly object _configurationSyncLock = new object();
/// <summary>
/// The configuration save lock.
/// </summary>
private readonly object _configurationSaveLock = new object();
private Action<string> _directoryCreateFn;
/// <summary>
/// The configuration.
/// </summary>
private TConfigurationType _configuration;
/// <summary>
/// Initializes a new instance of the <see cref="BasePlugin{TConfigurationType}" /> class.
/// </summary>
/// <param name="applicationPaths">The application paths.</param>
/// <param name="xmlSerializer">The XML serializer.</param>
protected BasePlugin(IApplicationPaths applicationPaths, IXmlSerializer xmlSerializer)
{
ApplicationPaths = applicationPaths;
XmlSerializer = xmlSerializer;
if (this is IPluginAssembly assemblyPlugin)
{
var assembly = GetType().Assembly;
var assemblyName = assembly.GetName();
var assemblyFilePath = assembly.Location;
// Find out the plugin folder.
bool inPluginFolder = assemblyFilePath.StartsWith(ApplicationPaths.PluginsPath, StringComparison.OrdinalIgnoreCase);
string path, dataFolderPath;
var configurationFileName = Path.ChangeExtension(Path.GetFileName(assemblyFilePath), ".xml");
if (inPluginFolder)
{
// Normal plugin.
path = assemblyFilePath.Substring(ApplicationPaths.PluginsPath.Length).Split('\\', StringSplitOptions.RemoveEmptyEntries)[0];
dataFolderPath = Path.Combine(
Path.Combine(ApplicationPaths.PluginsPath, path),
configurationFileName);
ConfigurationFilePath = dataFolderPath;
}
else
{
// Provider
dataFolderPath = Path.Combine(ApplicationPaths.PluginsPath, Path.GetFileNameWithoutExtension(assemblyFilePath));
ConfigurationFilePath = Path.Combine(ApplicationPaths.PluginConfigurationsPath, configurationFileName);
}
assemblyPlugin.SetAttributes(assemblyFilePath, dataFolderPath, assemblyName.Version);
var idAttributes = assembly.GetCustomAttributes(typeof(GuidAttribute), true);
if (idAttributes.Length > 0)
{
var attribute = (GuidAttribute)idAttributes[0];
var assemblyId = new Guid(attribute.Value);
assemblyPlugin.SetId(assemblyId);
}
// TODO : Simplify this, once migration support is ceased.
if (inPluginFolder)
{
var oldConfigFilePath = Path.Combine(ApplicationPaths.PluginConfigurationsPath, ConfigurationFileName);
if (!File.Exists(ConfigurationFilePath) && File.Exists(oldConfigFilePath))
{
// Migrate settings, as different plugin versions may have different settings.
try
{
File.Copy(oldConfigFilePath, ConfigurationFilePath);
}
catch
{
// Unable to migrate settings.
}
}
}
}
if (this is IHasPluginConfiguration hasPluginConfiguration)
{
hasPluginConfiguration.SetStartupInfo(s => Directory.CreateDirectory(s));
}
}
/// <summary>
/// Gets the application paths.
/// </summary>
/// <value>The application paths.</value>
protected IApplicationPaths ApplicationPaths { get; private set; }
/// <summary>
/// Gets the XML serializer.
/// </summary>
/// <value>The XML serializer.</value>
protected IXmlSerializer XmlSerializer { get; private set; }
/// <summary>
/// Gets the type of configuration this plugin uses.
/// </summary>
/// <value>The type of the configuration.</value>
public Type ConfigurationType => typeof(TConfigurationType);
/// <summary>
/// Gets or sets the event handler that is triggered when this configuration changes.
/// </summary>
public EventHandler<BasePluginConfiguration> ConfigurationChanged { get; set; }
/// <summary>
/// Gets the name the assembly file.
/// </summary>
/// <value>The name of the assembly file.</value>
protected string AssemblyFileName => Path.GetFileName(AssemblyFilePath);
/// <summary>
/// Gets or sets the plugin configuration.
/// </summary>
/// <value>The configuration.</value>
public TConfigurationType Configuration
{
get
{
// Lazy load
if (_configuration == null)
{
lock (_configurationSyncLock)
{
if (_configuration == null)
{
_configuration = LoadConfiguration();
}
}
}
return _configuration;
}
protected set => _configuration = value;
}
/// <summary>
/// Gets the name of the configuration file. Subclasses should override.
/// </summary>
/// <value>The name of the configuration file.</value>
public virtual string ConfigurationFileName => Path.ChangeExtension(AssemblyFileName, ".xml");
/// <summary>
/// Gets the full path to the configuration file.
/// </summary>
/// <value>The configuration file path.</value>
public string ConfigurationFilePath { get; }
/// <summary>
/// Gets the plugin configuration.
/// </summary>
/// <value>The configuration.</value>
BasePluginConfiguration IHasPluginConfiguration.Configuration => Configuration;
/// <inheritdoc />
public void SetStartupInfo(Action<string> directoryCreateFn)
{
// hack alert, until the .net core transition is complete
_directoryCreateFn = directoryCreateFn;
}
private TConfigurationType LoadConfiguration()
{
var path = ConfigurationFilePath;
try
{
return (TConfigurationType)XmlSerializer.DeserializeFromFile(typeof(TConfigurationType), path);
}
catch
{
var config = (TConfigurationType)Activator.CreateInstance(typeof(TConfigurationType));
SaveConfiguration(config);
return config;
}
}
/// <summary>
/// Saves the current configuration to the file system.
/// </summary>
/// <param name="config">Configuration to save.</param>
public virtual void SaveConfiguration(TConfigurationType config)
{
lock (_configurationSaveLock)
{
_directoryCreateFn(Path.GetDirectoryName(ConfigurationFilePath));
XmlSerializer.SerializeToFile(config, ConfigurationFilePath);
}
}
/// <summary>
/// Saves the current configuration to the file system.
/// </summary>
public virtual void SaveConfiguration()
{
SaveConfiguration(Configuration);
}
/// <inheritdoc />
public virtual void UpdateConfiguration(BasePluginConfiguration configuration)
{
if (configuration == null)
{
throw new ArgumentNullException(nameof(configuration));
}
Configuration = (TConfigurationType)configuration;
SaveConfiguration(Configuration);
ConfigurationChanged?.Invoke(this, configuration);
}
/// <inheritdoc />
public override PluginInfo GetPluginInfo()
{
var info = base.GetPluginInfo();
info.ConfigurationFileName = ConfigurationFileName;
return info;
}
}
}