/// <summary>
/// Branches the request pipeline based on the result of the given predicate.
/// </summary>
/// <param name="app"></param>
/// <param name="predicate">Invoked with the request environment to determine if the branch should be taken</param>
/// <param name="configuration">Configures a branch to take</param>
/// <returns></returns>
public static IApplicationBuilder MapWhen(this IApplicationBuilder app, Predicate predicate, Action<IApplicationBuilder> configuration)
{
if (app == null)
{
throw new ArgumentNullException(nameof(app));
}
if (predicate == null)
{
throw new ArgumentNullException(nameof(predicate));
}
if (configuration == null)
{
throw new ArgumentNullException(nameof(configuration));
}
// create branch
var branchBuilder = app.New();
configuration(branchBuilder);
var branch = branchBuilder.Build();
// put middleware in pipeline
var options = new MapWhenOptions
{
Predicate = predicate,
Branch = branch,
};
return app.Use(next => new MapWhenMiddleware(next, options).Invoke);
}
/// <summary>
/// Creates a new instance of <see cref="MapWhenMiddleware"/>.
/// </summary>
/// <param name="next">The delegate representing the next middleware in the request pipeline.</param>
/// <param name="options">The middleware options.</param>
public MapWhenMiddleware(RequestDelegate next, MapWhenOptions options)
{
if (next == null)
{
throw new ArgumentNullException(nameof(next));
}
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
if (options.Predicate == null)
{
throw new ArgumentException("Predicate not set on options.", nameof(options));
}
if (options.Branch == null)
{
throw new ArgumentException("Branch not set on options.", nameof(options));
}
_next = next;
_options = options;
}
public void NullArguments_ArgumentNullException()
{
var builder = new ApplicationBuilder(serviceProvider: null);
var noMiddleware = new ApplicationBuilder(serviceProvider: null).Build();
var noOptions = new MapWhenOptions();
Assert.Throws<ArgumentNullException>(() => builder.MapWhen(null, UseNotImplemented));
Assert.Throws<ArgumentNullException>(() => builder.MapWhen(NotImplementedPredicate, configuration: null));
Assert.Throws<ArgumentNullException>(() => new MapWhenMiddleware(null, noOptions));
Assert.Throws<ArgumentNullException>(() => new MapWhenMiddleware(noMiddleware, null));
Assert.Throws<ArgumentNullException>(() => new MapWhenMiddleware(null, noOptions));
Assert.Throws<ArgumentNullException>(() => new MapWhenMiddleware(noMiddleware, null));
}
public void NullArguments_ArgumentNullException()
{
var builder = new ApplicationBuilder(serviceProvider: null);
var noMiddleware = new ApplicationBuilder(serviceProvider: null).Build();
var noOptions = new MapWhenOptions();
Assert.Throws <ArgumentNullException>(() => builder.MapWhen(null !, UseNotImplemented));
Assert.Throws <ArgumentNullException>(() => builder.MapWhen(NotImplementedPredicate, configuration: null !));
Assert.Throws <ArgumentNullException>(() => new MapWhenMiddleware(null !, noOptions));
Assert.Throws <ArgumentNullException>(() => new MapWhenMiddleware(noMiddleware, null !));
Assert.Throws <ArgumentNullException>(() => new MapWhenMiddleware(null !, noOptions));
Assert.Throws <ArgumentNullException>(() => new MapWhenMiddleware(noMiddleware, null !));
}
/// <summary>
/// Creates a new instance of <see cref="MapWhenMiddleware"/>.
/// </summary>
/// <param name="next">The delegate representing the next middleware in the request pipeline.</param>
/// <param name="options">The middleware options.</param>
public MapWhenMiddleware(RequestDelegate next, MapWhenOptions options)
{
if (next == null)
{
throw new ArgumentNullException(nameof(next));
}
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
_next = next;
_options = options;
}
