/// <summary>
/// Determines the result of the specified context.
/// </summary>
/// <param name="context">The context.</param>
/// <returns>
/// A Decision indicating the result of the query.
/// </returns>
public async Task<bool> CheckAsync(DecisionContext context)
{
return await Task.Run(() =>
{
var expression = providers[context.Namespace].Inflate(context);
return expression(context);
});
}
/// <summary>
/// Gets the environment with the specified alias asynchronously.
/// </summary>
/// <param name="alias">The globally unique alias used to represent a specific environment.</param>
/// <param name="context">The context.</param>
/// <returns>
/// An environment, likely an instance of a class from an external assembly.
/// </returns>
public async Task<dynamic> GetAsync(string alias, DecisionContext context)
{
var result = cache.Get(Key(alias, context));
if (result == null)
{
result = await service.GetAsync(alias, context);
cache.Set(Key(alias, context), result, TimeSpan.FromSeconds(cacheDuration));
}
return result;
}
/// <summary>
/// Determines the result of the specified context.
/// </summary>
/// <param name="context">The context.</param>
/// <returns>
/// A Decision indicating the result of the query.
/// </returns>
public async Task<bool> CheckAsync(DecisionContext context)
{
var result = cache.Get(Key(context));
if (result == null)
{
result = new Decision { Id = context.Id, Result = await service.CheckAsync(context) };
cache.Set(Key(context), result, TimeSpan.FromSeconds(cacheDuration));
}
return result.Result;
}
public async Task<dynamic> GetAsync(string alias, DecisionContext context)
{
if (alias == LongAclEnvironment.ALIAS || alias == SimpleCounterEnvironment.ALIAS)
{
Thread.Sleep(TimeSpan.FromSeconds(3));
}
if (alias == SimpleCounterEnvironment.ALIAS)
{
return new SimpleCounterEnvironment(true);
}
return await Task.FromResult(environments[alias]);
}
public override bool Decide(DecisionContext context)
{
var envTask = GetEnvironmentAsync<AclEnvironment>(AclEnvironment.ALIAS, context);
envTask.Wait();
return envTask.Result.Entries.Any(a => a.Allow);
}
/// <summary>
/// Gets the environment with the specified key asynchronously.
/// </summary>
/// <param name="alias">The key.</param>
/// <param name="context">The context.</param>
/// <returns>
/// An environment, likely an instance of a class from an external assembly.
/// </returns>
public async Task<dynamic> GetAsync(string alias, DecisionContext context)
{
IEnvironmentProvider provider;
if (environments.TryGetValue(alias, out provider)) return await provider.GetAsync(alias, context);
throw new NotSupportedException(alias + " is not part of the supported Environments");
}
/// <summary>
/// Inflates the specified context into an expression that can be executed.
/// </summary>
/// <param name="context">The context.</param>
/// <returns>A delegate that takes a <see cref="DecisionContext"/> as a parameter to execute</returns>
public Predicate<DecisionContext> Inflate(DecisionContext context)
{
if (compiled.ContainsKey(context.Role) == false)
{
var expression = Expression.Lambda<Predicate<DecisionContext>>(Parse(expressions[context.Role]), PARAMETER);
var compiledExpression = expression.Compile();
compiled.AddOrUpdate(context.Role, compiledExpression, (key, oldValue) => compiledExpression);
}
return compiled[context.Role];
}
public override Task<dynamic> GetAsync(string alias, DecisionContext context)
{
throw new NotImplementedException();
}
/// <summary>
/// Make a decisions on the Decision of this policy for the provided <see cref="DecisionContext" />.
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
public override bool Decide(DecisionContext context)
{
return false;
}
/// <summary>
/// Creates a unique cache key for the alias and context
/// </summary>
/// <param name="alias">The alias.</param>
/// <param name="context">The context.</param>
/// <returns>A unique string representing the parameters</returns>
private static string Key(string alias, DecisionContext context)
{
return string.Format(CACHE_KEY_FORMAT, alias, context.Id);
}
public override bool Decide(DecisionContext context)
{
var envTask = GetEnvironmentAsync<CurrentUserEnvironment>(CurrentUserEnvironment.ALIAS, context);
envTask.Wait();
return envTask.Result.UserId == MatchUserId;
}
/// <summary>
/// Creates a unique cache key for the context
/// </summary>
/// <param name="context">The context.</param>
/// <returns>A unique string representing the parameters</returns>
private static string Key(DecisionContext context)
{
return context.Id;
}
/// <summary>
/// Make a decisions on the Decision of this policy for the provided <see cref="DecisionContext" />.
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
public override bool Decide(DecisionContext context)
{
return context.Target.id == Id;
}
/// <summary>
/// Determines the result of the specified context.
/// </summary>
/// <param name="service">The service.</param>
/// <param name="context">The context.</param>
/// <returns>
/// A Decision indicating the result of the query.
/// </returns>
public static bool Check(this IDecisionService service, DecisionContext context)
{
return Task.Run(() => service.CheckAsync(context)).Result;
}
