#1413 - Discovered mappings now get regex matchers removed.

We now remove potentially used regular expression matchers from template variables to avoid the to show up in links generated for the templates.

Backport of #1412.

src/main/java/org/springframework/hateoas/server/core/AnnotationMappingDiscoverer.java

@@ -24,6 +24,7 @@
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
+import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import org.springframework.http.HttpMethod;
@@ -43,6 +44,7 @@
 public class AnnotationMappingDiscoverer implements MappingDiscoverer {
 
 	private static final Pattern MULTIPLE_SLASHES = Pattern.compile("/{2,}");
+	private static final Pattern TEMPLATE_VARIABLE_NAME = Pattern.compile("\\{(.*)\\}");
 
 	private final Class<? extends Annotation> annotationType;
 	private final String mappingAttributeName;
@@ -116,7 +118,7 @@ public String getMapping(Class<?> type, Method method) {
 			return typeMapping;
 		}
 
-		return typeMapping == null || "/".equals(typeMapping) ? mapping[0] : join(typeMapping, mapping[0]);
+		return cleanup(typeMapping == null || "/".equals(typeMapping) ? mapping[0] : join(typeMapping, mapping[0]));
 	}
 
 	/**
@@ -179,6 +181,49 @@ private String[] getMappingFrom(@Nullable Annotation annotation) {
 	 * @return
 	 */
 	private static String join(String typeMapping, String mapping) {
-		return MULTIPLE_SLASHES.matcher(typeMapping.concat("/").concat(mapping)).replaceAll("/");
+		return typeMapping.concat("/").concat(mapping);
+	}
+
+	/**
+	 * @param mapping
+	 * @return
+	 */
+	private static String cleanup(String mapping) {
+
+		String[] parts = mapping.split("/");
+		StringBuilder result = new StringBuilder();
+
+		for (int i = 0; i < parts.length; i++) {
+
+			String part = parts[i];
+
+			if (i != 0) {
+				result.append("/");
+			}
+
+			result.append(part.contains(":") ? cleanupPart(part) : part);
+		}
+
+		return MULTIPLE_SLASHES.matcher(result.toString()).replaceAll("/");
+	}
+
+	private static String cleanupPart(String variable) {
+
+		if (!variable.contains("{")) {
+			return variable;
+		}
+
+		Matcher matcher = TEMPLATE_VARIABLE_NAME.matcher(variable);
+
+		if (!matcher.find()) {
+			return variable;
+		}
+
+		String rawName = matcher.group(1);
+		int colonIndex = rawName.indexOf(':');
+
+		return colonIndex < 0
+				? variable
+				: variable.replace(matcher.group(0), "{" + rawName.substring(0, colonIndex) + "}");
 	}
 }

src/test/java/org/springframework/hateoas/server/core/AnnotationMappingDiscovererUnitTest.java

@@ -25,7 +25,7 @@
 
 /**
  * Unit tests for {@link AnnotationMappingDiscoverer}.
- * 
+ *
  * @author Oliver Gierke
  * @author Kevin Conaway
  * @author Mark Paluch
@@ -153,6 +153,13 @@ void discoversMethodLevelMappingUsingComposedAnnotation() throws Exception {
 		assertThat(discoverer.getMapping(method)).isEqualTo("/type/otherMethod");
 	}
 
+	@Test // #1412
+	void removesMatchingExpressionFromTemplateVariable() throws Exception {
+
+		Method method = MyController.class.getMethod("mappingWithMatchingExpression");
+		assertThat(discoverer.getMapping(method)).isEqualTo("/type/foo/{bar}");
+	}
+
 	@RequestMapping("/type")
 	interface MyController {
 
@@ -164,6 +171,9 @@ interface MyController {
 
 		@RequestMapping
 		void noMethodMapping();
+
+		@RequestMapping("/foo/{bar:[ABC]{1}}")
+		void mappingWithMatchingExpression();
 	}
 
 	interface ControllerWithoutTypeLevelMapping {

src/test/java/org/springframework/hateoas/server/core/PropertyResolvingMappingDiscovererUnitTest.java

@@ -24,8 +24,6 @@
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.hateoas.TestUtils;
-import org.springframework.hateoas.server.core.AnnotationMappingDiscoverer;
-import org.springframework.hateoas.server.core.PropertyResolvingMappingDiscoverer;
 import org.springframework.mock.web.MockServletContext;
 import org.springframework.test.context.TestPropertySource;
 import org.springframework.test.context.junit.jupiter.web.SpringJUnitWebConfig;