Add Let´s Chat notifications

spring-boot-admin-docs/src/main/asciidoc/server-notifications.adoc

@@ -241,3 +241,41 @@ account and configure it appropriately.
 | `+++"*#{application.name}* (#{application.id}) is *#{to.status}*"+++`
 |
 |===
+
+[letschat-notifications]
+==== Let´s Chat notifications ====
+To enable Let´s Chat notifications you need to add the host url and add the API token and username from Let´s Chat
+
+.Let´s Chat notifications configuration options
+|===
+| Property name |Description |Default value
+
+| spring.boot.admin.notify.letschat.enabled
+| Enable let´s Chat notifications
+| `true`
+
+| spring.boot.admin.notify.letschat.ignore-changes
+| Comma-delimited list of status changes to be ignored. Format: "<from-status>:<to-status>". Wildcards allowed.
+| `"UNKNOWN:UP"`
+
+| spring.boot.admin.notify.letschat.url
+| The let´s Chat Host URL to send notifications
+|
+
+| spring.boot.admin.notify.letschat.room
+| the room where to send the messages
+|
+
+| spring.boot.admin.notify.letschat.token
+| the token to access the let´s Chat API
+|
+
+| spring.boot.admin.notify.letschat.username
+| The username for which the token was created
+| `Spring Boot Admin`
+
+| spring.boot.admin.notify.letschat.message
+| Message to use in the event. SpEL-expressions are supported
+| `+++"*#{application.name}* (#{application.id}) is *#{to.status}*"+++`
+|
+|===

spring-boot-admin-server/src/main/java/de/codecentric/boot/admin/config/NotifierConfiguration.java

@@ -40,6 +40,7 @@ import de.codecentric.boot.admin.notify.Notifier;
 import de.codecentric.boot.admin.notify.NotifierListener;
 import de.codecentric.boot.admin.notify.PagerdutyNotifier;
 import de.codecentric.boot.admin.notify.SlackNotifier;
+import de.codecentric.boot.admin.notify.LetsChatNotifier;
 import de.codecentric.boot.admin.notify.filter.FilteringNotifier;
 import de.codecentric.boot.admin.notify.filter.web.NotificationFilterController;
 import de.codecentric.boot.admin.web.PrefixHandlerMapping;
@@ -161,4 +162,16 @@ public class NotifierConfiguration {
 		}
 	}
 
+	@Configuration
+	@ConditionalOnProperty(prefix = "spring.boot.admin.notify.letschat", name = "url")
+	@AutoConfigureBefore({ NotifierListenerConfiguration.class,
+			CompositeNotifierConfiguration.class })
+	public static class LetsChatNotifierConfiguration {
+		@Bean
+		@ConditionalOnMissingBean
+		@ConfigurationProperties("spring.boot.admin.notify.letschat")
+		public LetsChatNotifier letsChatNotifier() {
+			return new LetsChatNotifier();
+		}
+	}
 }

spring-boot-admin-server/src/main/java/de/codecentric/boot/admin/notify/LetsChatNotifier.java

+/*
+ * Copyright 2014-2017 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 de.codecentric.boot.admin.notify;
+
+import java.net.URI;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.springframework.expression.Expression;
+import org.springframework.expression.ParserContext;
+import org.springframework.expression.spel.standard.SpelExpressionParser;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
+import org.springframework.util.Base64Utils;
+import org.springframework.web.client.RestTemplate;
+
+import de.codecentric.boot.admin.event.ClientApplicationEvent;
+
+
+/**
+ * Notifier submitting events to let´s Chat.
+ *
+ * @author Rico Pahlisch
+ */
+public class LetsChatNotifier extends AbstractStatusChangeNotifier {
+	private static final String DEFAULT_MESSAGE = "*#{application.name}* (#{application.id}) is *#{to.status}*";
+
+	private final SpelExpressionParser parser = new SpelExpressionParser();
+	private RestTemplate restTemplate = new RestTemplate();
+
+	/**
+	 * Host URL for Let´s Chat
+	 */
+	private URI url;
+
+	/**
+	 * Name of the room
+	 */
+	private String room;
+
+	/**
+	 * Token for the Let´s chat API
+	 */
+	private String token;
+
+	/**
+	 * username which sends notification
+	 */
+	private String username = "Spring Boot Admin";
+
+	/**
+	 * Message template. SpEL template using event as root
+	 */
+	private Expression message;
+
+	public LetsChatNotifier() {
+		this.message = parser.parseExpression(DEFAULT_MESSAGE, ParserContext.TEMPLATE_EXPRESSION);
+	}
+
+	@Override
+	protected void doNotify(ClientApplicationEvent event) throws Exception {
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentType(MediaType.APPLICATION_JSON);
+		// Let's Chat requiers the token as basic username, the password can be an arbitrary string.
+		String auth = Base64Utils.encodeToString(String.format("%s:%s", token, username).getBytes());
+		headers.add(HttpHeaders.AUTHORIZATION, String.format("Basic %s", auth));
+		restTemplate.exchange(createUrl(), HttpMethod.POST, new HttpEntity<>(createMessage(event), headers), Void.class);
+	}
+
+	private URI createUrl() {
+		return URI.create(String.format("%s/rooms/%s/messages", url, room));
+	}
+
+	public void setRestTemplate(RestTemplate restTemplate) {
+		this.restTemplate = restTemplate;
+	}
+
+	public void setUrl(URI url) {
+		this.url = url;
+	}
+
+	public void setUsername(String username) {
+		this.username = username;
+	}
+
+	public void setRoom(String room) {
+		this.room = room;
+	}
+
+	public void setToken(String token) {
+		this.token = token;
+	}
+
+	public void setMessage(String message) {
+		this.message = parser.parseExpression(message, ParserContext.TEMPLATE_EXPRESSION);
+	}
+
+	protected Object createMessage(ClientApplicationEvent event) {
+		Map<String, String> messageJson = new HashMap<>();
+		messageJson.put("text", getText(event));
+		return messageJson;
+	}
+
+	protected String getText(ClientApplicationEvent event) {
+		return message.getValue(event, String.class);
+	}
+}

spring-boot-admin-server/src/test/java/de/codecentric/boot/admin/notify/LetsChatNotifierTest.java

+package de.codecentric.boot.admin.notify;
+
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+
+import java.net.URI;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
+import org.springframework.util.Base64Utils;
+import org.springframework.web.client.RestTemplate;
+
+import de.codecentric.boot.admin.event.ClientApplicationStatusChangedEvent;
+import de.codecentric.boot.admin.model.Application;
+import de.codecentric.boot.admin.model.StatusInfo;
+
+public class LetsChatNotifierTest {
+	private static final String room = "text_room";
+	private static final String token = "text_token";
+	private static final String user = "api_user";
+	private static final String appName = "App";
+	private static final String id = "-id-";
+	private static final String host = "http://localhost";
+
+	private LetsChatNotifier notifier;
+	private RestTemplate restTemplate;
+
+	@Before
+	public void setUp() {
+		restTemplate = mock(RestTemplate.class);
+		notifier = new LetsChatNotifier();
+		notifier.setUsername(user);
+		notifier.setUrl(URI.create(host));
+		notifier.setRoom(room);
+		notifier.setToken(token);
+		notifier.setRestTemplate(restTemplate);
+	}
+
+	@Test
+	public void test_onApplicationEvent_resolve() {
+		StatusInfo infoDown = StatusInfo.ofDown();
+		StatusInfo infoUp = StatusInfo.ofUp();
+
+		notifier.notify(getEvent(infoDown, infoUp));
+
+		HttpEntity<?> expected = expectedMessage(standardMessage(infoUp.getStatus(), appName, id));
+		verify(restTemplate).exchange(eq(URI.create(String.format("%s/rooms/%s/messages", host, room))), eq(HttpMethod.POST), eq(expected), eq(Void.class));
+	}
+
+	@Test
+	public void test_onApplicationEvent_resolve_with_custom_message() {
+		StatusInfo infoDown = StatusInfo.ofDown();
+		StatusInfo infoUp = StatusInfo.ofUp();
+
+		notifier.setMessage("TEST");
+		notifier.notify(getEvent(infoDown, infoUp));
+
+		HttpEntity<?> expected = expectedMessage("TEST");
+		verify(restTemplate).exchange(eq(URI.create(String.format("%s/rooms/%s/messages", host, room))), eq(HttpMethod.POST), eq(expected), eq(Void.class));
+	}
+
+	private ClientApplicationStatusChangedEvent getEvent(StatusInfo infoDown, StatusInfo infoUp) {
+		return new ClientApplicationStatusChangedEvent(
+				Application.create(appName).withId(id).withHealthUrl("http://health").build(),
+				infoDown, infoUp);
+	}
+
+	private HttpEntity<?> expectedMessage(String message) {
+		HttpHeaders httpHeaders = new HttpHeaders();
+		httpHeaders.setContentType(MediaType.APPLICATION_JSON);
+		String auth = Base64Utils.encodeToString(String.format("%s:%s", token, user).getBytes());
+		httpHeaders.add(HttpHeaders.AUTHORIZATION, String.format("Basic %s", auth));
+		Map<String, Object> messageJson = new HashMap<>();
+		messageJson.put("text", message);
+		return new HttpEntity<>(messageJson, httpHeaders);
+	}
+
+	private String standardMessage(String status, String appName, String id) {
+		return "*" + appName + "* (" + id + ") is *" + status + "*";
+	}
+
+}