using relative path for swagger ui

Author: Robert Diers

src/main/java/org/opentesting/util/OpenApiConfig.java

@@ -0,0 +1,22 @@
+package org.opentesting.util;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import io.swagger.v3.oas.models.OpenAPI;
+import io.swagger.v3.oas.models.servers.Server;
+
+/**
+ * fix https server URL in swagger when using a dispatcher
+ */
+@Configuration
+public class OpenApiConfig {
+
+    @Bean
+    public OpenAPI openAPI(@Value("${server.servlet.context-path}") String contextPath) {
+        return new OpenAPI()
+                .addServersItem(new Server().url(contextPath));
+    }
+    
+}

src/main/resources/application.yml

@@ -23,6 +23,8 @@ app:
 
 server:
   port: 50000
+  servlet:
+    context-path: /
   shutdown: graceful
 
 spring:

src/test/resources/application.yml

@@ -16,6 +16,8 @@ app:
 
 server:
   port: 50000
+  servlet:
+    context-path: /
   shutdown: graceful
 
 spring: