diff options
Diffstat (limited to 'libs/VNLib.Plugins.Sessions.Cache.Client/src/RemoteSession.cs')
| -rw-r--r-- | libs/VNLib.Plugins.Sessions.Cache.Client/src/RemoteSession.cs | 170 |
1 files changed, 67 insertions, 103 deletions
diff --git a/libs/VNLib.Plugins.Sessions.Cache.Client/src/RemoteSession.cs b/libs/VNLib.Plugins.Sessions.Cache.Client/src/RemoteSession.cs index af2c969..421d07d 100644 --- a/libs/VNLib.Plugins.Sessions.Cache.Client/src/RemoteSession.cs +++ b/libs/VNLib.Plugins.Sessions.Cache.Client/src/RemoteSession.cs @@ -1,5 +1,5 @@ /* -* Copyright (c) 2022 Vaughn Nugent +* Copyright (c) 2023 Vaughn Nugent * * Library: VNLib * Package: VNLib.Plugins.Sessions.Cache.Client @@ -23,85 +23,49 @@ */ using System; -using System.Threading; -using System.Threading.Tasks; using System.Collections.Generic; -using Microsoft.VisualStudio.Threading; - -using VNLib.Net.Http; -using VNLib.Data.Caching.Exceptions; using VNLib.Utils.Extensions; using VNLib.Plugins.Essentials.Sessions; using VNLib.Plugins.Essentials.Extensions; + namespace VNLib.Plugins.Sessions.Cache.Client { /// <summary> /// Base class for cacheable lazy initialized session entires /// that exist in a remote caching server /// </summary> - public abstract class RemoteSession : SessionBase + public abstract class RemoteSession : SessionBase, IRemoteSession { protected const string CREATED_TIME_ENTRY = "__.i.ctime"; - - protected IRemoteCacheStore Client { get; } - protected TimeSpan UpdateTimeout { get; } - private readonly AsyncLazyInitializer Initializer; - /// <summary> - /// The lazy loaded data-store + /// The session data store /// </summary> - protected Dictionary<string, string>? DataStore; - - protected RemoteSession(string sessionId, IRemoteCacheStore client, TimeSpan backgroundTimeOut) - { - SessionID = sessionId; - UpdateTimeout = backgroundTimeOut; - Client = client; - Initializer = new(InitializeAsync, null); - } + protected readonly IDictionary<string, string> DataStore; /// <summary> - /// The data initializer, loads the data store from the connected cache server + /// The reason that the session was destroyed if an error occured /// </summary> - /// <returns>A task that completes when the get operation completes</returns> - protected virtual async Task InitializeAsync() - { - //Setup timeout cancellation for the get, to cancel it - using CancellationTokenSource cts = new(UpdateTimeout); - //get or create a new session - DataStore = await Client.GetObjectAsync<Dictionary<string, string>>(SessionID, cancellationToken: cts.Token); - } - /// <summary> - /// Updates the current sessin agaisnt the cache store - /// </summary> - /// <returns>A task that complets when the update has completed</returns> - protected virtual async Task ProcessUpdateAsync() - { - //Setup timeout cancellation for the update, to cancel it - using CancellationTokenSource cts = new(UpdateTimeout); - await Client.AddOrUpdateObjectAsync(SessionID, null, DataStore, cts.Token); - } + protected Exception? ErrorCause { get; set; } + /// <summary> - /// Delets the current session in the remote store + /// Initialzies a new session /// </summary> - /// <returns>A task that completes when instance has been deleted</returns> - protected virtual async Task ProcessDeleteAsync() + /// <param name="sessionId">The id of the current session</param> + /// <param name="initialData">The initial data</param> + /// <param name="isNew">A flag that determines if the session is considered new</param> + protected RemoteSession(string sessionId, IDictionary<string, string> initialData, bool isNew) { - //Setup timeout cancellation for the update, to cancel it - using CancellationTokenSource cts = new(UpdateTimeout); - try - { - await Client.DeleteObjectAsync(SessionID, cts.Token); - } - catch (ObjectNotFoundException) - { - //This is fine, if the object does not exist, nothing to invalidate - } + SessionID = sessionId; + DataStore = initialData; + IsNew = isNew; } - + + ///<inheritdoc/> + public override string SessionID { get; } + ///<inheritdoc/> public override DateTimeOffset Created { @@ -113,15 +77,14 @@ namespace VNLib.Plugins.Sessions.Cache.Client return DateTimeOffset.FromUnixTimeMilliseconds(unixMs); } - protected set => this.SetValueType(CREATED_TIME_ENTRY, value.ToUnixTimeMilliseconds()); - } - + set => this.SetValueType(CREATED_TIME_ENTRY, value.ToUnixTimeMilliseconds()); + } ///<inheritdoc/> protected override string IndexerGet(string key) { //Get the value at the key or an empty string as a default - return DataStore!.GetValueOrDefault(key, string.Empty); + return DataStore.GetValueOrDefault(key) ?? string.Empty; } ///<inheritdoc/> protected override void IndexerSet(string key, string value) @@ -130,59 +93,60 @@ namespace VNLib.Plugins.Sessions.Cache.Client if (value == null) { //Set modified flag - IsModified |= DataStore!.Remove(key); + IsModified |= DataStore.Remove(key); } else { //Store the value at the specified key - DataStore![key] = value; + DataStore[key] = value; IsModified = true; } } + - - /* - * If the data-store is not found it means the session does not - * exist in cache, so its technically not dangerous to reuse, - * so the new mask needs to be set, but the old ID is going - * to be reused - */ + ///<inheritdoc/> + public virtual SessionStatus GetStatus() + { + SessionStatus status = SessionStatus.None; - /// <summary> - /// Waits for exclusive access to the session, and initializes - /// session data (loads it from the remote store) - /// </summary> - /// <param name="entity">The event to attach a session to</param> - /// <param name="cancellationToken">A token to cancel the operaion</param> - /// <returns></returns> - public virtual async Task WaitAndLoadAsync(IHttpEvent entity, CancellationToken cancellationToken) + status |= Flags.IsSet(INVALID_MSK) ? SessionStatus.Delete : SessionStatus.None; + status |= Flags.IsSet(REGEN_ID_MSK) ? SessionStatus.RegenId : SessionStatus.None; + status |= Flags.IsSet(MODIFIED_MSK) ? SessionStatus.UpdateOnly: SessionStatus.None; + + return status; + } + + ///<inheritdoc/> + public virtual IDictionary<string, string> GetSessionData() => DataStore; + + ///<inheritdoc/> + public virtual void Destroy(Exception? cause) { - //Wait for exclusive access - await base.WaitOneAsync(cancellationToken); - try - { - //Lazily initalize the current instance - await Initializer.InitializeAsync(cancellationToken); - //See if data-store is null (new session was created - if (DataStore == null) - { - //New session was created - DataStore = new(10); - //Set is-new flag - Flags.Set(IS_NEW_MSK); - //Set created time - Created = DateTimeOffset.UtcNow; - //Init ipaddress - UserIP = entity.Server.GetTrustedIp(); - //Set modified flag so session will be updated - IsModified = true; - } - } - catch - { - MainLock.Release(); - throw; - } + //Set invalid status + ErrorCause = cause; + Flags.Set(INVALID_MSK); + + //Clear all session data + DataStore.Clear(); + } + + ///<inheritdoc/> + public virtual bool IsValid(out Exception? cause) + { + /* + * Were reusing the invalid mask assuming that when a session is invalidated + * it will be deleted and destroyed + */ + + cause = ErrorCause; + return !Flags.IsSet(INVALID_MSK); + } + + ///<inheritdoc/> + public virtual void SessionUpdateComplete() + { + //Reset flags + Flags.ClearAll(); } } } |