Add Token Exchange grant to demo-client sample

Issue gh-60

samples/demo-client/src/main/java/sample/web/AuthorizationController.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2023 the original author or authors.
+ * Copyright 2020-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -41,11 +41,14 @@ import static org.springframework.security.oauth2.client.web.reactive.function.c
 public class AuthorizationController {
 	private final WebClient webClient;
 	private final String messagesBaseUri;
+	private final String userMessagesBaseUri;
 
 	public AuthorizationController(WebClient webClient,
-			@Value("${messages.base-uri}") String messagesBaseUri) {
+			@Value("${messages.base-uri}") String messagesBaseUri,
+			@Value("${user-messages.base-uri}") String userMessagesBaseUri) {
 		this.webClient = webClient;
 		this.messagesBaseUri = messagesBaseUri;
+		this.userMessagesBaseUri = userMessagesBaseUri;
 	}
 
 	@GetMapping(value = "/authorize", params = "grant_type=authorization_code")
@@ -96,6 +99,21 @@ public class AuthorizationController {
 		return "index";
 	}
 
+	@GetMapping(value = "/authorize", params = "grant_type=token_exchange")
+	public String tokenExchangeGrant(Model model) {
+
+		String[] messages = this.webClient
+				.get()
+				.uri(this.userMessagesBaseUri)
+				.attributes(clientRegistrationId("user-client-authorization-code"))
+				.retrieve()
+				.bodyToMono(String[].class)
+				.block();
+		model.addAttribute("messages", messages);
+
+		return "index";
+	}
+
 	@GetMapping(value = "/authorize", params = "grant_type=device_code")
 	public String deviceCodeGrant() {
 		return "device-activate";

samples/demo-client/src/main/resources/application.yml

@@ -38,6 +38,14 @@ spring:
             authorization-grant-type: client_credentials
             scope: message.read,message.write
             client-name: messaging-client-client-credentials
+          user-client-authorization-code:
+            provider: spring
+            client-id: messaging-client
+            client-secret: secret
+            authorization-grant-type: authorization_code
+            redirect-uri: "http://127.0.0.1:8080/authorized"
+            scope: user.read
+            client-name: user-client-authorization-code
           messaging-client-device-code:
             provider: spring
             client-id: device-messaging-client
@@ -51,3 +59,6 @@ spring:
 
 messages:
   base-uri: http://127.0.0.1:8090/messages
+
+user-messages:
+  base-uri: http://127.0.0.1:8091/user/messages

samples/demo-client/src/main/resources/templates/page-templates.html

@@ -25,6 +25,7 @@
                     <ul class="dropdown-menu">
                         <li><a class="dropdown-item" href="/authorize?grant_type=authorization_code" th:href="@{/authorize?grant_type=authorization_code}">Authorization Code</a></li>
                         <li><a class="dropdown-item" href="/authorize?grant_type=client_credentials" th:href="@{/authorize?grant_type=client_credentials}">Client Credentials</a></li>
+                        <li><a class="dropdown-item" href="/authorize?grant_type=token_exchange" th:href="@{/authorize?grant_type=token_exchange}">Token Exchange</a></li>
                         <li><a class="dropdown-item" href="/authorize?grant_type=device_code" th:href="@{/authorize?grant_type=device_code}">Device Code</a></li>
                     </ul>
                 </li>