feat(new-rocket-api): Implement message sending (see #JENKINS-40595)

src/main/java/jenkins/plugins/rocketchatnotifier/model/Message.java

@@ -4,6 +4,9 @@ public class Message {
 
   private String msg;
 
+  public Message() {
+  }
+
   public Message(String messsage) {
     this.msg = messsage;
   }

src/main/java/jenkins/plugins/rocketchatnotifier/rocket/RocketChatClient.java

@@ -38,6 +38,13 @@ public interface RocketChatClient {
 
   void send(Room room, String message) throws ValidatorException, IOException;
 
-  void send(String room, String message) throws ValidatorException, IOException;
+  /**
+   *
+   * @param channelName
+   * @param message
+   * @throws ValidatorException
+   * @throws IOException
+   */
+  void send(String channelName, String message) throws ValidatorException, IOException;
 
 }

src/main/java/jenkins/plugins/rocketchatnotifier/rocket/RocketChatClientImpl.java

@@ -6,6 +6,8 @@
 import sun.security.validator.ValidatorException;
 
 import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Client for Rocket.Chat which relies on the REST API v1.
@@ -69,11 +71,18 @@ public Room[] getChannels() throws IOException {
 
   @Override
   public void send(Room room, String message) throws ValidatorException, IOException {
-
+    this.send(room.getName(), message);
   }
 
   @Override
-  public void send(String room, String message) throws ValidatorException, IOException {
-
+  public void send(String channelName, String message) throws ValidatorException, IOException {
+    Map body = new HashMap<String, String>();
+    body.put("channel", "#" + channelName);
+    body.put("text", message);
+    Response res = this.callBuilder.buildCall(RocketChatRestApiV1.PostMessage,
+      null, body);
+    if (!res.isSuccessful()) {
+      throw new IOException("The send of the message was unsuccessful.");
+    }
   }
 }

src/main/java/jenkins/plugins/rocketchatnotifier/rocket/RocketChatRestApiV1.java

@@ -24,7 +24,11 @@ public enum RocketChatRestApiV1 {
   /**
    * Retrieves a list of all the channels in the server.
    */
-  ChannelsInfo("channels.info", HttpMethods.GET, true);
+  ChannelsInfo("channels.info", HttpMethods.GET, true),
+  /**
+   * Retrieves a list of all the channels in the server.
+   */
+  PostMessage("chat.postMessage", HttpMethods.POST, true);
 
   private String methodName;
   private HttpMethods httpMethod;

src/test/java/jenkins/plugins/rocketchatnotifier/rocket/RocketChatClientIT.java

@@ -24,4 +24,11 @@ public void shouldReadRooms() throws Exception {
     Room[] rooms = this.client.getChannels();
     assertThat(rooms.length, is(1));
   }
+
+  @Test
+  public void shouldSendMessage() throws Exception {
+    this.client.send("general", "test");
+  }
+
+
 }