public async Task ApplyAsync(HttpContext httpContext, CandidateSet candidates)
{
if (httpContext == null)
{
throw new ArgumentNullException(nameof(httpContext));
}
if (candidates == null)
{
throw new ArgumentNullException(nameof(candidates));
}
DynamicPageEndpointSelector?selector = null;
// There's no real benefit here from trying to avoid the async state machine.
// We only execute on nodes that contain a dynamic policy, and thus always have
// to await something.
for (var i = 0; i < candidates.Count; i++)
{
if (!candidates.IsValidCandidate(i))
{
continue;
}
var endpoint = candidates[i].Endpoint;
var originalValues = candidates[i].Values;
RouteValueDictionary?dynamicValues = null;
// We don't expect both of these to be provided, and they are internal so there's
// no realistic way this could happen.
var dynamicPageMetadata = endpoint.Metadata.GetMetadata <DynamicPageMetadata>();
var transformerMetadata = endpoint.Metadata.GetMetadata <DynamicPageRouteValueTransformerMetadata>();
DynamicRouteValueTransformer?transformer = null;
if (dynamicPageMetadata != null)
{
dynamicValues = dynamicPageMetadata.Values;
}
else if (transformerMetadata != null)
{
transformer = (DynamicRouteValueTransformer)httpContext.RequestServices.GetRequiredService(transformerMetadata.SelectorType);
if (transformer.State != null)
{
throw new InvalidOperationException(Resources.FormatStateShouldBeNullForRouteValueTransformers(transformerMetadata.SelectorType.Name));
}
transformer.State = transformerMetadata.State;
dynamicValues = await transformer.TransformAsync(httpContext, originalValues !);
}
else
{
// Not a dynamic page
continue;
}
if (dynamicValues == null)
{
candidates.ReplaceEndpoint(i, null, null);
continue;
}
selector = ResolveSelector(selector, endpoint);
var endpoints = selector.SelectEndpoints(dynamicValues);
if (endpoints.Count == 0 && dynamicPageMetadata != null)
{
// Having no match for a fallback is a configuration error. We can't really check
// during startup that the action you configured exists, so this is the best we can do.
throw new InvalidOperationException(
"Cannot find the fallback endpoint specified by route values: " +
"{ " + string.Join(", ", dynamicValues.Select(kvp => $"{kvp.Key}: {kvp.Value}")) + " }.");
}
else if (endpoints.Count == 0)
{
candidates.ReplaceEndpoint(i, null, null);
continue;
}
// We need to provide the route values associated with this endpoint, so that features
// like URL generation work.
var values = new RouteValueDictionary(dynamicValues);
// Include values that were matched by the fallback route.
if (originalValues != null)
{
foreach (var kvp in originalValues)
{
values.TryAdd(kvp.Key, kvp.Value);
}
}
if (transformer != null)
{
endpoints = await transformer.FilterAsync(httpContext, values, endpoints);
if (endpoints.Count == 0)
{
candidates.ReplaceEndpoint(i, null, null);
continue;
}
}
// Update the route values
candidates.ReplaceEndpoint(i, endpoint, values);
var loadedEndpoints = new List <Endpoint>(endpoints);
for (var j = 0; j < loadedEndpoints.Count; j++)
{
var metadata = loadedEndpoints[j].Metadata;
var actionDescriptor = metadata.GetMetadata <PageActionDescriptor>();
if (actionDescriptor is CompiledPageActionDescriptor)
{
// Nothing to do here. The endpoint already represents a compiled page.
}
else
{
// We're working with a runtime-compiled page and have to Load it.
var compiled = actionDescriptor !.CompiledPageDescriptor ??
await _loader.LoadAsync(actionDescriptor, endpoint.Metadata);
loadedEndpoints[j] = compiled.Endpoint !;
}
}
// Expand the list of endpoints
candidates.ExpandEndpoint(i, loadedEndpoints, _comparer);
}
}
private async Task <IEnumerable <AreaInfo> > GetAreaInfosAsync(IActionDescriptorCollectionProvider actionDescriptorCollectionProvider, PageLoader pageLoader, LinkGenerator linkGenerator)
{
//根，从area开始
var result = new List <AreaInfo>();
//遍历区域
foreach (var area in actionDescriptorCollectionProvider.ActionDescriptors.Items.GroupBy(item => item.RouteValues["area"]))
{
var areaInfo = new AreaInfo {
Name = area.Key
};
result.Add(areaInfo);
//遍历控制器
foreach (var controllerActions in area.OfType <ControllerActionDescriptor>().GroupBy(c => c.ControllerTypeInfo))
{
//跳过重复控制器，不知道为什么，里面有些重复项目
if (areaInfo.Controllers.Any(c => c.TypeFullName == controllerActions.Key.FullName))
{
continue;
}
var conInfo = new AreaInfo.ControllerInfo
{
Name = controllerActions.First().ControllerName,
TypeFullName = controllerActions.Key.FullName,
Description = (controllerActions.Key.GetCustomAttribute(typeof(DescriptionAttribute)) as DescriptionAttribute)
?.Description,
Area = controllerActions.First().RouteValues["area"],
};
areaInfo.Controllers.Add(conInfo);
//遍历动作
foreach (var action in controllerActions)
{
var act = new AreaInfo.ControllerInfo.ActionInfo
{
Name = action.MethodInfo.Name,
ActionName = action.ActionName,
HandlerIdentification = (action.MethodInfo.GetCustomAttribute(typeof(RequestHandlerIdentificationAttribute)) as RequestHandlerIdentificationAttribute)
?.UniqueKey,
Signature = action.MethodInfo.ToString(),
Description = (action.MethodInfo.GetCustomAttribute(typeof(DescriptionAttribute)) as DescriptionAttribute)
?.Description,
Url = linkGenerator.GetPathByAction(action.ActionName, conInfo.Name, new { area = conInfo.Area }),
HttpMethodLimits = action.ActionConstraints?.OfType <HttpMethodActionConstraint>().FirstOrDefault()?.HttpMethods.ToList(),
MethodInfo = action.MethodInfo,
ActionDescriptor = action
};
conInfo.Actions.Add(act);
}
}
//遍历Razor Page
foreach (var pageActionDescriptor in area.OfType <PageActionDescriptor>())
{
//载入Razor Page，会从程序集加载或编译page文件并缓存
var page = await pageLoader.LoadAsync(pageActionDescriptor);
//也是剔除重复
if (areaInfo.Pages.Any(p => p.TypeFullName == page.HandlerTypeInfo.FullName))
{
continue;
}
var pageInfo = new AreaInfo.PageInfo
{
Name = page.DisplayName,
Area = page.AreaName,
TypeFullName = page.HandlerTypeInfo.FullName,
Description = (page.HandlerTypeInfo.GetCustomAttribute(typeof(DescriptionAttribute)) as DescriptionAttribute)
?.Description
};
foreach (var handlerMethod in page.HandlerMethods)
{
pageInfo.PageHandlers.Add(new AreaInfo.PageInfo.PageHandlerInfo
{
HttpMethod = handlerMethod.HttpMethod,
Name = handlerMethod.Name,
HandlerIdentification = (handlerMethod.MethodInfo.GetCustomAttribute(typeof(RequestHandlerIdentificationAttribute)) as RequestHandlerIdentificationAttribute)
?.UniqueKey,
Signature = handlerMethod.MethodInfo.ToString(),
Description = (handlerMethod.MethodInfo.GetCustomAttribute(typeof(DescriptionAttribute)) as DescriptionAttribute)
?.Description,
Url = linkGenerator.GetPathByPage(page.DisplayName, handlerMethod.Name, new { area = page.AreaName }),
MethodInfo = handlerMethod.MethodInfo,
ActionDescriptor = page
});
}
areaInfo.Pages.Add(pageInfo);
}
}
return(result);
}