using System;
using System.Threading.Tasks;
using Swan;
namespace EmbedIO.Routing
{
///
/// Base class for modules that handle requests by resolving route / method pairs associated with handlers.
///
///
public abstract class RoutingModuleBase : WebModuleBase
{
private readonly RouteVerbResolverCollection _resolvers = new RouteVerbResolverCollection(nameof(RoutingModuleBase));
///
///
/// Initializes a new instance of the class.
///
protected RoutingModuleBase(string baseRoute)
: base(baseRoute)
{
}
///
public override bool IsFinalHandler => true;
///
protected override async Task OnRequestAsync(IHttpContext context)
{
var result = await _resolvers.ResolveAsync(context).ConfigureAwait(false);
switch (result)
{
case RouteResolutionResult.RouteNotMatched:
case RouteResolutionResult.NoHandlerSuccessful:
await OnPathNotFoundAsync(context).ConfigureAwait(false);
break;
case RouteResolutionResult.NoHandlerSelected:
await OnMethodNotAllowedAsync(context).ConfigureAwait(false);
break;
case RouteResolutionResult.Success:
return;
default:
throw SelfCheck.Failure($"Internal error: unknown route resolution result {result}.");
}
}
///
/// Associates a HTTP method and a route to a handler.
///
/// A constant representing the HTTP method
/// to associate with , or
/// if can handle all HTTP methods.
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void AddHandler(HttpVerbs verb, RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(verb, matcher, handler);
///
/// Associates a HTTP method and a route to a synchronous handler.
///
/// A constant representing the HTTP method
/// to associate with , or
/// if can handle all HTTP methods.
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void AddHandler(HttpVerbs verb, RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(verb, matcher, handler);
///
/// Adds handlers, associating them with HTTP method / route pairs by means
/// of Route attributes.
/// See for further information.
///
/// Where to look for compatible handlers.
/// The number of handlers that were added.
/// is .
protected int AddHandlersFrom(object target)
=> _resolvers.AddFrom(target);
///
/// Associates all requests matching a route to a handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnAny(RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Any, matcher, handler);
///
/// Associates all requests matching a route to a synchronous handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnAny(RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Any, matcher, handler);
///
/// Associates DELETE requests matching a route to a handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnDelete(RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Delete, matcher, handler);
///
/// Associates DELETE requests matching a route to a synchronous handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnDelete(RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Delete, matcher, handler);
///
/// Associates GET requests matching a route to a handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnGet(RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Get, matcher, handler);
///
/// Associates GET requests matching a route to a synchronous handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnGet(RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Get, matcher, handler);
///
/// Associates HEAD requests matching a route to a handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnHead(RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Head, matcher, handler);
///
/// Associates HEAD requests matching a route to a synchronous handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnHead(RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Head, matcher, handler);
///
/// Associates OPTIONS requests matching a route to a handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnOptions(RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Options, matcher, handler);
///
/// Associates OPTIONS requests matching a route to a synchronous handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnOptions(RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Options, matcher, handler);
///
/// Associates PATCH requests matching a route to a handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnPatch(RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Patch, matcher, handler);
///
/// Associates PATCH requests matching a route to a synchronous handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnPatch(RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Patch, matcher, handler);
///
/// Associates POST requests matching a route to a handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnPost(RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Post, matcher, handler);
///
/// Associates POST requests matching a route to a synchronous handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnPost(RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Post, matcher, handler);
///
/// Associates PUT requests matching a route to a handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnPut(RouteMatcher matcher, RouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Put, matcher, handler);
///
/// Associates PUT requests matching a route to a synchronous handler.
///
/// The used to match URL paths.
/// A callback used to handle matching contexts.
///
/// is .
/// - or -
/// is .
///
protected void OnPut(RouteMatcher matcher, SyncRouteHandlerCallback handler)
=> _resolvers.Add(HttpVerbs.Put, matcher, handler);
///
/// Called when no route is matched for the requested URL path.
/// The default behavior is to send an empty 404 Not Found response.
///
/// The context of the request being handled.
/// A representing the ongoing operation.
protected virtual Task OnPathNotFoundAsync(IHttpContext context)
=> throw HttpException.NotFound();
///
/// Called when at least one route is matched for the requested URL path,
/// but none of them is associated with the HTTP method of the request.
/// The default behavior is to send an empty 405 Method Not Allowed response.
///
/// The context of the request being handled.
/// A representing the ongoing operation.
protected virtual Task OnMethodNotAllowedAsync(IHttpContext context)
=> throw HttpException.MethodNotAllowed();
}
}