public Dictionary <string, List <string> > GetDuplicateEndpoints(EndpointDataSource dataSource)
{
// get the DfaMatcherBuilder - internal, so needs reflection :(
Type matcherBuilder = typeof(IEndpointSelectorPolicy).Assembly
.GetType("Microsoft.AspNetCore.Routing.Matching.DfaMatcherBuilder");
var rawBuilder = _services.GetRequiredService(matcherBuilder);
IDfaMatcherBuilder builder = rawBuilder.ActLike <IDfaMatcherBuilder>();
var endpoints = dataSource.Endpoints;
for (var i = 0; i < endpoints.Count; i++)
{
if (endpoints[i] is RouteEndpoint endpoint && (endpoint.Metadata.GetMetadata <ISuppressMatchingMetadata>()?.SuppressMatching ?? false) == false)
{
builder.AddEndpoint(endpoint);
}
}
// Assign each node a sequential index.
var visited = new Dictionary <IDfaNode, int>();
var duplicates = new Dictionary <string, List <string> >();
var rawTree = builder.BuildDfaTree(includeLabel: true);
IDfaNode tree = rawTree.ActLike <IDfaNode>();
Visit(tree, LogDuplicates);
return(duplicates);
void LogDuplicates(IDfaNode node)
{
if (!visited.TryGetValue(node, out var label))
{
label = visited.Count;
visited.Add(node, label);
}
// We can safely index into visited because this is a post-order traversal,
// all of the children of this node are already in the dictionary.
var matchCount = node?.Matches?.Count ?? 0;
if (matchCount > 1)
{
var duplicateEndpoints = node.Matches.Select(x => x.DisplayName).ToList();
duplicates[node.Label] = duplicateEndpoints;
}
}
}
static void Visit(IDfaNode node, Action <IDfaNode> visitor)
{
if (node.Literals?.Values != null)
{
foreach (var dictValue in node.Literals.Values)
{
IDfaNode value = dictValue.ActLike <IDfaNode>();
Visit(value, visitor);
}
}
// Break cycles
if (node.Parameters != null && !ReferenceEquals(node, node.Parameters))
{
IDfaNode parameters = node.Parameters.ActLike <IDfaNode>();
Visit(parameters, visitor);
}
// Break cycles
if (node.CatchAll != null && !ReferenceEquals(node, node.CatchAll))
{
IDfaNode catchAll = node.CatchAll.ActLike <IDfaNode>();
Visit(catchAll, visitor);
}
if (node.PolicyEdges?.Values != null)
{
foreach (var dictValue in node.PolicyEdges.Values)
{
IDfaNode value = dictValue.ActLike <IDfaNode>();
Visit(value, visitor);
}
}
visitor(node);
}
public void Write(EndpointDataSource dataSource, TextWriter writer)
{
// get the DfaMatcherBuilder - internal, so needs reflection :(
Type matcherBuilder = typeof(IEndpointSelectorPolicy).Assembly
.GetType("Microsoft.AspNetCore.Routing.Matching.DfaMatcherBuilder");
var rawBuilder = _services.GetRequiredService(matcherBuilder);
IDfaMatcherBuilder builder = rawBuilder.ActLike <IDfaMatcherBuilder>();
var endpoints = dataSource.Endpoints;
for (var i = 0; i < endpoints.Count; i++)
{
if (endpoints[i] is RouteEndpoint endpoint && (endpoint.Metadata.GetMetadata <ISuppressMatchingMetadata>()?.SuppressMatching ?? false) == false)
{
builder.AddEndpoint(endpoint);
}
}
// Assign each node a sequential index.
var visited = new Dictionary <IDfaNode, int>();
var rawTree = builder.BuildDfaTree(includeLabel: true);
IDfaNode tree = rawTree.ActLike <IDfaNode>();
writer.WriteLine("digraph DFA {");
Visit(tree, WriteNode);
writer.WriteLine("}");
void WriteNode(IDfaNode node)
{
if (!visited.TryGetValue(node, out var label))
{
label = visited.Count;
visited.Add(node, label);
}
// We can safely index into visited because this is a post-order traversal,
// all of the children of this node are already in the dictionary.
if (node.Literals != null)
{
foreach (DictionaryEntry dictEntry in node.Literals)
{
var key = (string)dictEntry.Key;
IDfaNode value = dictEntry.Value.ActLike <IDfaNode>();
writer.WriteLine($"{label} -> {visited[value]} [label=\"/{key}\" {_options.LiteralEdge}]");
}
}
if (node.Parameters != null)
{
IDfaNode parameters = node.Parameters.ActLike <IDfaNode>();
writer.WriteLine($"{label} -> {visited[parameters]} [label=\"/*\" {_options.ParametersEdge}]");
}
if (node.CatchAll != null && node.Parameters != node.CatchAll)
{
IDfaNode catchAll = node.CatchAll.ActLike <IDfaNode>();
writer.WriteLine($"{label} -> {visited[catchAll]} [label=\"/**\" {_options.CatchAllEdge}]");
}
if (node.PolicyEdges != null)
{
foreach (DictionaryEntry dictEntry in node.PolicyEdges)
{
var key = (object)dictEntry.Key;
IDfaNode value = dictEntry.Value.ActLike <IDfaNode>();
writer.WriteLine($"{label} -> {visited[value]} [label=\"{key}\" {_options.PolicyEdge}]");
}
}
var matchCount = node?.Matches?.Count ?? 0;
var extras = matchCount > 0 ? _options.MatchingNode : _options.DefaultNode;
writer.WriteLine($"{label} [label=\"{node.Label}\" {extras}]");
}
}