Add OAuth2 Client HandlerMethodArgumentResolver

Fixes gh-4651

samples/boot/oauth2login/src/main/java/sample/web/OAuth2LoginController.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2002-2018 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package sample.web;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.security.oauth2.client.OAuth2AuthorizedClient;
+import org.springframework.security.oauth2.client.annotation.OAuth2Client;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.util.StringUtils;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.reactive.function.client.ClientRequest;
+import org.springframework.web.reactive.function.client.ExchangeFilterFunction;
+import org.springframework.web.reactive.function.client.WebClient;
+import reactor.core.publisher.Mono;
+
+import java.util.Collections;
+import java.util.Map;
+
+/**
+ * @author Joe Grandja
+ */
+@Controller
+public class OAuth2LoginController {
+
+	@GetMapping("/")
+	public String index(Model model, @OAuth2Client OAuth2AuthorizedClient authorizedClient) {
+		model.addAttribute("userName", authorizedClient.getPrincipalName());
+		model.addAttribute("clientName", authorizedClient.getClientRegistration().getClientName());
+		return "index";
+	}
+
+	@GetMapping("/userinfo")
+	public String userinfo(Model model, @OAuth2Client OAuth2AuthorizedClient authorizedClient) {
+		Map userAttributes = Collections.emptyMap();
+		String userInfoEndpointUri = authorizedClient.getClientRegistration()
+			.getProviderDetails().getUserInfoEndpoint().getUri();
+		if (!StringUtils.isEmpty(userInfoEndpointUri)) {	// userInfoEndpointUri is optional for OIDC Clients
+			userAttributes = WebClient.builder()
+				.filter(oauth2Credentials(authorizedClient))
+				.build()
+				.get()
+				.uri(userInfoEndpointUri)
+				.retrieve()
+				.bodyToMono(Map.class)
+				.block();
+		}
+		model.addAttribute("userAttributes", userAttributes);
+		return "userinfo";
+	}
+
+	private ExchangeFilterFunction oauth2Credentials(OAuth2AuthorizedClient authorizedClient) {
+		return ExchangeFilterFunction.ofRequestProcessor(
+			clientRequest -> {
+				ClientRequest authorizedRequest = ClientRequest.from(clientRequest)
+					.header(HttpHeaders.AUTHORIZATION, "Bearer " + authorizedClient.getAccessToken().getTokenValue())
+					.build();
+				return Mono.just(authorizedRequest);
+			});
+	}
+}