Add support for Sort GroupedOpenApi by name. Fixes #398

Author: bnasslahsen

Diff for: springdoc-openapi-common/src/main/java/org/springdoc/core/SwaggerUiConfigProperties.java

@@ -20,6 +20,7 @@
 
 import java.net.URL;
 import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
@@ -152,6 +153,8 @@ public class SwaggerUiConfigProperties {
 
 	private String url;
 
+	private Direction groupsOrder = Direction.ASC;
+
 	public static void addGroup(String group) {
 		SwaggerUrl swaggerUrl = new SwaggerUrl(group);
 		swaggerUrls.add(swaggerUrl);
@@ -372,7 +375,13 @@ public boolean isValidUrl(String url) {
 	}
 
 	private void put(String urls, List<SwaggerUrl> swaggerUrls, Map<String, Object> params) {
-		swaggerUrls = swaggerUrls.stream().filter(elt -> StringUtils.isNotEmpty(elt.getUrl())).collect(Collectors.toList());
+		Comparator<SwaggerUrl> swaggerUrlComparator;
+		if (groupsOrder.isAscending())
+			swaggerUrlComparator = (h1, h2) -> h1.getName().compareTo(h2.getName());
+		else
+			swaggerUrlComparator = (h1, h2) -> h2.getName().compareTo(h1.getName());
+
+		swaggerUrls = swaggerUrls.stream().sorted(swaggerUrlComparator).filter(elt -> StringUtils.isNotEmpty(elt.getUrl())).collect(Collectors.toList());
 		if (!CollectionUtils.isEmpty(swaggerUrls)) {
 			params.put(urls, swaggerUrls);
 		}
@@ -408,4 +417,25 @@ public void setName(String name) {
 			this.name = name;
 		}
 	}
+
+	static enum Direction {
+		ASC,
+		DESC;
+
+		public boolean isAscending() {
+			return this.equals(ASC);
+		}
+
+		public boolean isDescending() {
+			return this.equals(DESC);
+		}
+	}
+
+	public Direction getGroupsOrder() {
+		return groupsOrder;
+	}
+
+	public void setGroupsOrder(Direction groupsOrder) {
+		this.groupsOrder = groupsOrder;
+	}
 }

Diff for: springdoc-openapi-ui/src/test/java/test/org/springdoc/ui/app4/SpringDocApp4Test.java

@@ -25,11 +25,14 @@
 import org.springdoc.core.SwaggerUiConfigProperties;
 import test.org.springdoc.ui.AbstractSpringDocTest;
 
+import org.springframework.test.context.TestPropertySource;
+
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 
+@TestPropertySource(properties = "springdoc.swagger-ui.groups-order=DESC")
 public class SpringDocApp4Test extends AbstractSpringDocTest {
 
 	@Test