Improve path matching in RESTEasy Reactive for ambiguous path templates

The PathMatcher now returns list of all possible matches rather than
just the first match. This is for case when the first match end up not
matching the request path, the remaining, lower priority matches, can be
tried.

Author: TomasHofman

independent-projects/resteasy-reactive/server/runtime/src/main/java/org/jboss/resteasy/reactive/server/mapping/PathMatcher.java

@@ -1,5 +1,6 @@
 package org.jboss.resteasy.reactive.server.mapping;
 
+import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
 import java.util.Set;
@@ -34,24 +35,28 @@ class PathMatcher<T> implements Dumpable {
      * @param path The relative path to match
      * @return The match match. This will never be null, however if none matched its value field will be
      */
-    PathMatch<T> match(String path) {
+    List<PathMatch<T>> match(String path) {
         int length = path.length();
         final int[] lengths = this.lengths;
+        ArrayList<PathMatch<T>> matches = new ArrayList<>(1);
         for (int i = 0; i < lengths.length; ++i) {
             int pathLength = lengths[i];
             if (pathLength == length) {
                 SubstringMap.SubstringMatch<T> next = paths.get(path, length);
                 if (next != null) {
-                    return new PathMatch<>(path, "", next.getValue());
+                    matches.add(new PathMatch<>(path, "", next.getValue()));
                 }
             } else if (pathLength < length) {
                 SubstringMap.SubstringMatch<T> next = paths.get(path, pathLength);
                 if (next != null) {
-                    return new PathMatch<>(next.getKey(), path.substring(pathLength), next.getValue());
+                    matches.add(new PathMatch<>(next.getKey(), path.substring(pathLength), next.getValue()));
                 }
             }
         }
-        return defaultMatch(path);
+        if (matches.isEmpty()) {
+            matches.add(defaultMatch(path));
+        }
+        return matches;
     }
 
     PathMatch<T> defaultMatch(String path) {

independent-projects/resteasy-reactive/server/runtime/src/main/java/org/jboss/resteasy/reactive/server/mapping/RequestMapper.java

@@ -4,6 +4,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.function.BiConsumer;
 import java.util.regex.Matcher;
@@ -48,9 +49,12 @@ public void accept(String stem, ArrayList<RequestPath<T>> list) {
      * @return best RequestMatch, or null if the path has no match
      */
     public RequestMatch<T> map(String path) {
-        var result = mapFromPathMatcher(path, requestPaths.match(path), 0);
-        if (result != null) {
-            return result;
+        List<PathMatcher.PathMatch<ArrayList<RequestPath<T>>>> matches = requestPaths.match(path);
+        for (int i = 0; i < matches.size(); i++) {
+            var result = mapFromPathMatcher(path, matches.get(i), 0);
+            if (result != null) {
+                return result;
+            }
         }
 
         // the following code is meant to handle cases like https://github.com/quarkusio/quarkus/issues/30667
@@ -68,16 +72,21 @@ public RequestMatch<T> continueMatching(String path, RequestMatch<T> lastMatch)
             return null;
         }
 
-        var initialMatches = requestPaths.match(path);
-        var result = mapFromPathMatcher(path, initialMatches, 0);
-        if (result != null) {
-            int idx = nextMatchStartingIndex(initialMatches, lastMatch);
-            return mapFromPathMatcher(path, initialMatches, idx);
+        var initialMatchesList = requestPaths.match(path);
+        for (int i = 0; i < initialMatchesList.size(); i++) {
+            var result = mapFromPathMatcher(path, initialMatchesList.get(i), 0);
+            if (result != null) {
+                int idx = nextMatchStartingIndex(initialMatchesList.get(i), lastMatch);
+                RequestMatch<T> match = mapFromPathMatcher(path, initialMatchesList.get(i), idx);
+                if (match != null) {
+                    return match;
+                }
+            }
         }
 
         // the following code is meant to handle cases like https://github.com/quarkusio/quarkus/issues/30667
-        initialMatches = requestPaths.defaultMatch(path);
-        result = mapFromPathMatcher(path, initialMatches, 0);
+        var initialMatches = requestPaths.defaultMatch(path);
+        var result = mapFromPathMatcher(path, initialMatches, 0);
         if (result != null) {
             int idx = nextMatchStartingIndex(initialMatches, lastMatch);
             return mapFromPathMatcher(path, initialMatches, idx);

independent-projects/resteasy-reactive/server/vertx/src/test/java/org/jboss/resteasy/reactive/server/vertx/test/matching/PathParamOverlapTest.java

@@ -53,6 +53,36 @@ public void test() {
         get("/hello/other/test/wrong")
                 .then()
                 .statusCode(404);
+
+        get("/hello/foo")
+                .then()
+                .statusCode(404);
+
+        get("/hello/foo/value")
+                .then()
+                .statusCode(200)
+                .body(equalTo("Foo value"));
+
+        get("/hello/foo/bar")
+                .then()
+                .statusCode(200)
+                .body(equalTo("Foo bar"));
+
+        get("/hello/foo/bar/value")
+                .then()
+                .statusCode(200)
+                .body(equalTo("FooBar value"));
+
+        get("/hello/foo/bah_value")
+                .then()
+                .statusCode(200)
+                .body(equalTo("Foo bah_value"));
+
+        get("/hello/foo/bar_value")
+                .then()
+                .statusCode(200)
+                .body(equalTo("Foo bar_value"));
+
     }
 
     @Path("/hello")
@@ -70,5 +100,19 @@ public String test() {
         public String second(@RestPath String id) {
             return "Hello " + id;
         }
+
+        @GET
+        @Path("/foo/{param}")
+        public String foo(@RestPath String param) {
+            return "Foo " + param;
+        }
+
+        @GET
+        @Path("/foo/bar/{param}")
+        public String fooBar(@RestPath String param) {
+            return "FooBar " + param;
+        }
+
     }
+
 }